#emc | Logs for 2006-04-02

[00:00:27] <alex_joni> roltek: what lines do you mean?
[00:01:47] <roltek> N5G0X.35Z-3.8986
[00:01:47] <roltek> N6X.21
[00:01:47] <roltek> N7G33Z-1.0031F.05
[00:02:39] <roltek> desription is a thread going from z.1 to z-1.0
[00:03:20] <alex_joni> I guess that's a problem with synergy then?
[00:03:58] <Imperator_> hm, maybe G32 is Fanuc stuff DIN66025 doesn't know it, the Siemens 840D controller also
[00:04:10] <roltek> that's a problem for anybody that your telling them that this is a good program
[00:04:53] <alex_joni> roltek: who's telling that?
[00:04:57] <roltek> g33 is also not in hass
[00:05:26] <roltek> the 2 most used control's in the us are fanuc and hass
[00:05:55] <alex_joni> is that hass or haas?
[00:06:01] <roltek> sieman's has very little market share in us
[00:06:15] <roltek> bad spelling
[00:08:07] <Imperator_> hm where can i find the aktual ISO standard, i think we have to look there, because every controller has its own standards
[00:09:18] <alex_joni> Imperator_: there are things that aren't defined in the iso standard
[00:09:23] <roltek> did seiman's make iso standard for cnc control's
[00:09:26] <alex_joni> and that's the reason this is not standard
[00:09:38] <alex_joni> roltek: he means the rs274
[00:09:53] <alex_joni> it's EIA not ISO, but close
[00:10:02] <Imperator_> ok
[00:11:09] <roltek> i don't know where you can find standards
[00:11:17] <alex_joni> you can buy them
[00:11:38] <roltek> it is completely up to you what you make emc standards
[00:11:55] <alex_joni> roltek: right now we're trying to gather data of what others do
[00:12:00] <alex_joni> and try to get with the flow
[00:12:46] <roltek> logical thinking is if a hobbist uses emc and decidese to open a shop his next machine will be a haas
[00:14:09] <roltek> now he will note be able to use his programs he used before
[00:14:27] <roltek> the g code will have changed
[00:16:04] <Imperator_> if he is in the US ... In Europe he buys a Gildemeister with Siemens controller, in russia .... china
[00:17:08] <roltek> in the us we don't use seimens
[00:17:20] <jmkasunich> so?
[00:17:26] <jmkasunich> the us is only part of the world
[00:17:35] <Imperator_> :-)
[00:18:00] <roltek> i have used siemen's on cnc gear cutting controls
[00:18:20] <alex_joni> imagine US 600 years ago ;)
[00:18:27] <Imperator_> in machine tools germany is leading that is the reason why Siemens often makes the standards there
[00:18:38] <roltek> was emc started at nist or china
[00:18:38] <alex_joni> no HAAS, no Fanuc ;)
[00:19:20] <Imperator_> started at nist developed in the world
[00:20:04] <fenn> * fenn pokes alex.. what do they use in romania
[00:20:15] <alex_joni> fenn : different stuff
[00:20:27] <alex_joni> seen them all, can't say which are more common though
[00:21:07] <fenn> rs274 really doesn't define any lathe codes.?
[00:22:18] <fenn> we should call up some tiny controller manufacturer and see what they do
[00:22:46] <fenn> "alo, is this okuma? yeah what code do you guys use for threading?"
[00:23:43] <fenn> they have both g32 and g33
[00:25:07] <roltek> i am not sure but is g33 for a varible lead thread where you are side cutting
[00:25:54] <alex_joni> G33
[00:25:54] <alex_joni> Threadcutting, constant lead
[00:26:13] <alex_joni> 34 & 35 are variable lead..
[00:26:25] <roltek> ok
[00:26:43] <fenn> maybe we should mail petro @ machinetoolhelp.com
[00:29:22] <fenn> * fenn yawns
[00:29:27] <alex_joni> maybe I should go to bed
[00:29:29] <alex_joni> :)
[00:29:33] <alex_joni> gnight all
[00:29:44] <Imperator_> night
[00:29:58] <roltek> see you later i am out of here too
[00:30:11] <Imperator_> the other question is what is RS274
[00:30:27] <alex_joni> Imperator_: the g-code standard
[00:30:33] <alex_joni> but there are at least 4 versions of it
[00:30:40] <alex_joni> I think -D is the last one?
[00:30:42] <Imperator_> realy ???
[00:30:44] <alex_joni> might be wrong though
[00:31:11] <Imperator_> here in germany it is DIN/ISO 66025
[00:32:06] <Imperator_> i never heard something about RS274 only at the EMC project everybody speeks about
[00:33:04] <alex_joni> http://en.wikipedia.org/wiki/G-code
[00:33:09] <alex_joni> too late
[00:33:58] <alex_joni> cradek: that link I just pasted, has a nice lathe example :D
[00:34:22] <fenn> hmm it says g33 for fanuc threading
[00:34:35] <alex_joni> lol
[00:34:42] <alex_joni> wikipedia doesn't lie
[00:35:08] <alex_joni> that's almost like google lying.. not gonna happen/be accepted
[00:35:31] <fenn> well i wouldn't bet my life on it
[00:35:57] <Imperator_> :-)
[00:36:14] <fenn> so is g96 always ft/min or is it also m/min
[00:36:28] <alex_joni> depending on G21/G20
[00:36:41] <alex_joni> http://en.wikipedia.org/wiki/G-code
[00:36:45] <alex_joni> Imperator_: you missed that
[00:36:59] <alex_joni> Imperator_: http://www.isd.mel.nist.gov/personnel/kramer/pubs/RS274NGC_3.web/RS274NGC_3.html#1001717
[00:37:22] <alex_joni> Imperator_: "RS274 is a programming language for numerically controlled (NC) machine tools, which has been used for many years. The most recent standard version of RS274 is RS274-D, which was completed in 1979. It is described in the document "EIA Standard EIA-274-D" by the Electronic Industries Association [EIA]."
[00:37:50] <Imperator_> ok
[00:38:25] <Imperator_> is that the right association ?? What about ISO
[00:39:25] <Imperator_> in germany everything was DIN Deutsche Industrie Norm = German industry standard, now everything is ISO
[00:39:51] <alex_joni> ANSI is the big standards corporation
[00:39:58] <alex_joni> and ANSI supervises both EIA and ISO
[00:40:21] <alex_joni> but EIA is for some industrial stuff, including g-code
[00:41:02] <Imperator_> hm
[00:41:23] <Imperator_> uff 2:40 am
[00:41:25] <Imperator_> here
[00:42:06] <Imperator_> in romania it is 3:40 right ?
[00:44:11] <alex_joni> 3:45 right now
[00:44:31] <alex_joni> EIA RS 274 B 1968
[00:44:31] <alex_joni> EIA RS 274 C 1978
[00:44:32] <alex_joni> EIA RS 274 D 1980
[00:45:45] <fenn> i think EIA is involved because rs-274 was used to draw circuit board traces with photoplotting machines
[00:46:07] <cradek> no wonder it's so absurd - it's 25 years old
[00:47:59] <alex_joni> the latest
[00:48:07] <alex_joni> version A is 50 years old
[00:48:43] <fenn> so that means the original was around before computers were invented
[00:48:52] <skunkworks> our k&t which was designed in the 60's with a ge controller has most of the same commands as todays controllers. It would only conture radiuses of 9.9999 inches though ;)
[00:49:30] <skunkworks> you needed leading zeros though - it didn't see decimal points
[00:49:32] <alex_joni> fenn: almost
[00:49:47] <Imperator_> found something DIN66025 = ISO/DIS6983 Numerical control of machines -- Program format and definition of address words
[00:50:16] <fenn> hmm i was wrong, the Z1 computer was invented in 1936 :P
[00:52:33] <fenn> amazing.. it has a floating point processor
[00:53:10] <Imperator_> http://webstore.ansi.org/ansidocstore/product.asp?sku=ISO+6983-1%3A1982
[00:53:20] <Imperator_> $62 nice
[00:54:06] <fenn> bah
[00:55:14] <Imperator_> i think the right one is ISO 6983
[00:59:16] <Imperator_> and it should maybe identical with RS274D
[01:02:57] <Imperator_> whatever cu
[01:18:42] <asdfqwega> logger_aj, bookmark
[01:18:42] <asdfqwega> See http://solaris.cs.utt.ro/irc/irc.freenode.net:6667/emc/2006-04-02#T01-18-42
[03:03:07] <cradek_> cradek_ is now known as cradek
[04:05:28] <dmessier> allo
[04:11:25] <Jymmm> hey dmessier
[04:11:53] <dmessier> sup jymmm
[04:12:06] <Jymmm> ssdd
[04:12:27] <dmessier> i see...
[04:12:40] <Jymmm> Same shit, different day
[04:13:20] <dmessier> i got it
[04:14:19] <dmessier> you ever seen a pic of the v22 osprey tilt -a-rotar airplane??
[04:14:51] <fenn> i've seen a pic of the gear that turns the propeller - it had a huge chunk missing and they stuck it in anyway!
[04:16:14] <dmessier> i work with the guy who made the machine to grind that gear
[04:16:52] <dmessier> helical face gear technology
[04:17:45] <dmessier> we just won the contract to mfg the re-designed nose gear
[04:18:32] <dmessier> it will lift a 10 000 lb payload and carry it 100 miles
[04:22:22] <fenn> i was reading an article about how they crash a lot
[04:22:27] <dmessier> at 250 knots
[04:22:39] <fenn> because that gear failed :)
[04:22:50] <dmessier> they lost 2 in a row in 2000
[04:23:09] <dmessier> was the drive shaft arrangement i heard
[04:24:28] <dmessier> there was a major redesign as they were grounded
[04:25:45] <dmessier> since 2004 they have had raves
[04:26:48] <dmessier> want a news letter??
[04:27:42] <dmessier> Tilt-rotor Sheds Troubled Past
[04:27:43] <dmessier> Osprey could be ready to deploy by 2007
[04:38:32] <dmessier> the latest screw up was a lack of de-icing capability...
[08:15:41] <anonimasu> hnm
[08:15:44] <anonimasu> morning
[09:03:03] <robin__> indeed it is.
[09:10:13] <Imperator_> logger_aj:bookmark
[09:10:13] <Imperator_> See http://solaris.cs.utt.ro/irc/irc.freenode.net:6667/emc/2006-04-02#T09-10-13
[09:34:44] <alex_joni> * alex_joni opens his eyes slowly
[09:34:55] <alex_joni> ewww.. all that light :(
[09:37:13] <fenn> morning alex
[09:40:49] <ValarQ> 'lo folks
[09:46:14] <anonimasu> mornin
[09:46:14] <anonimasu> g
[09:55:57] <robin__> alex_joni, beware the evil day-star
[09:56:13] <anonimasu> hm
[09:57:10] <giacus> logger_aj: bookmark
[09:57:10] <giacus> See http://solaris.cs.utt.ro/irc/irc.freenode.net:6667/emc/2006-04-02#T09-57-10
[10:23:33] <alex_joni> robin__: how's it?
[10:23:49] <giacus> hello
[10:23:58] <alex_joni> mornign giacus
[10:24:01] <ValarQ> g'day mr giacus
[10:24:05] <alex_joni> mroning ;)
[10:24:12] <giacus> hello ValarQ
[10:24:26] <alex_joni> hello captain
[10:25:58] <fenn> * fenn salutes
[10:26:50] <alex_joni> howdy fenn, ain't it a bit late there?
[10:26:59] <alex_joni> or is it early ?
[10:27:07] <fenn> its late i need to go to beeeeed
[10:27:47] <fenn> please explain to DanF_DrC why usb is such a bad idea
[10:28:07] <ValarQ> is there any hardware recomendations for emc2?
[10:29:51] <alex_joni> where's DanF_DrC ?
[10:30:03] <alex_joni> ValarQ: what hardware? PC? or cards?
[10:30:29] <ValarQ> cpu
[10:30:39] <alex_joni> 200MHz+
[10:30:56] <fenn> there ought to be a wiki page for that
[10:31:07] <fenn> i can never remember which is the "good" one and which is the "bad" one
[10:31:28] <alex_joni> fenn: what do you mean?
[10:31:35] <fenn> people kept asking that at cnc-workshop and i was like.. uhhh they all work i guess
[10:31:45] <alex_joni> there are no really bad ones
[10:31:45] <fenn> "which computer should i use to run emc"
[10:32:06] <fenn> apparently some intels are really high latency
[10:32:17] <alex_joni> the problem is that people tend to think that modern computers 2GHz will work twice as fast as older 1GHz machines
[10:32:20] <alex_joni> and that's not true
[10:32:39] <alex_joni> the older the CPU, the better the latency relative to that CPU frequency
[10:33:06] <alex_joni> so probably a 386-DX-40 behaves the most predictable for RT stuff (lots better than a 2GHz P4)
[10:33:23] <alex_joni> the problem is that you want speed too ;), so the DX40 gets ruled out
[10:33:38] <alex_joni> so the overall problem is finding a balanced middle ground
[10:34:01] <alex_joni> somewhere around 400-2000 MHz should be OK under any circumstances
[10:34:27] <fenn> why do you need such processing power? isnt most of the latency from the isa bus?
[10:34:38] <fenn> * fenn wants numbers dammit
[10:34:42] <ValarQ> isn't base_period quite dependent on the cpu clock?
[10:34:43] <alex_joni> fenn: right, if you talk about parport stepping & such
[10:34:54] <alex_joni> ValarQ, fenn: you are both right
[10:35:04] <fenn> jmk mentioned you could get gprof-ish numbers if he turned some kernel timer back on
[10:35:13] <fenn> i think that was the one that broke stuff
[10:35:17] <alex_joni> fenn: gprof ?
[10:35:33] <fenn> gprof tells you how many times a particular function gets called and how long it takes to execute etc etc
[10:35:38] <alex_joni> fenn: I am running 5.9 usec BASE_THREAD on my Athlon XP 1600+
[10:36:01] <ValarQ> the reason i ask is that i'm having some problem with "joint error":s again
[10:36:05] <alex_joni> fenn: right, but on some kernel&RTAI combinations turning that on will make it run 20-times slower (or even slower)
[10:36:12] <alex_joni> ValarQ: what setup? what emc2?
[10:36:18] <ValarQ> yeah
[10:36:31] <ValarQ> i had to tweak the base_period setting
[10:36:40] <alex_joni> ValarQ: what value are you running now?
[10:36:51] <alex_joni> and again, what emc?
[10:37:08] <ValarQ> latest cvs
[10:37:22] <ValarQ> BASE_PERIOD = 0.000250
[10:37:26] <alex_joni> ok, what hardware? and what distro ?
[10:37:33] <alex_joni> ValarQ: that's INSANELY high
[10:37:46] <ValarQ> x86 P3 600MHz debian
[10:37:55] <alex_joni> you should be running 0.000025
[10:37:56] <ValarQ> i do know it is high
[10:38:13] <alex_joni> but 0.000050 (the default) should work ok for you
[10:38:19] <alex_joni> why did you turn it up?
[10:38:31] <ValarQ> i had problems with my system locking
[10:38:45] <ValarQ> maybe i was to fast tweaking the wrong setting?
[10:38:53] <alex_joni> oh, and btw. the latest CVS doesn't use 0.000050 but 50000 nsec instead
[10:39:05] <fenn> ugh
[10:39:11] <ValarQ> since when?
[10:39:13] <fenn> whats the point of that?
[10:39:19] <alex_joni> #+ Base task period, in nanosecs - this is the fastest thread in the machine
[10:39:19] <alex_joni> BASE_PERIOD = 50000
[10:39:34] <alex_joni> fenn: removing insmod motmod from the emc runscript
[10:39:44] <alex_joni> now loadrt motmod from the hal file
[10:39:50] <alex_joni> ValarQ: a few days
[10:40:00] <fenn> hal still cant do simple multiplication?
[10:40:08] <alex_joni> nope
[10:40:17] <fenn> * fenn grumbles
[10:40:27] <alex_joni> do it, don't grumble
[10:40:34] <fenn> i dont know where to begin
[10:40:42] <ValarQ> alex_joni: ok, i haven't updated it in a couple of days...
[10:41:06] <alex_joni> ValarQ: it would be best for you if you checkout the TESTING tag
[10:41:13] <alex_joni> that's the latest proven version
[10:41:22] <alex_joni> and that tag gets moved when we think it's ok to move it
[10:41:28] <alex_joni> HEAD might be broken once in a while
[10:41:31] <fenn> i'd have to extend the "hal description language" i guess
[10:41:42] <alex_joni> fenn: right, it's not that trivial
[10:41:48] <ValarQ> alex_joni: ok
[10:41:56] <alex_joni> ValarQ: co -rTESTING emc2
[10:41:58] <ValarQ> is the developer cvs down?
[10:42:03] <alex_joni> ValarQ: yes :(
[10:42:08] <alex_joni> since wednesday
[10:42:11] <ValarQ> ow
[10:42:23] <alex_joni> and now it's the weekend, and SF doesn't give a damn
[10:42:31] <alex_joni> * alex_joni hates that
[10:43:04] <ValarQ> problematic when using cvs
[10:43:14] <alex_joni> and the biggest problem, this is not the first time it happens
[10:43:21] <alex_joni> ValarQ: use anon checkout, that works
[10:43:53] <ValarQ> well, i can't reach the machine on a week anyway...
[10:44:20] <alex_joni> ValarQ: bottom line, the 650MHz machine should be plenty
[10:44:34] <alex_joni> err.. 600 ;)
[10:44:47] <ValarQ> ok, i won't buy a new supercomputer just for emc2 in a while then :)
[10:45:15] <alex_joni> ValarQ: have a user running a 300MHzish PC with 64MB ram, emc2+AXIS
[10:45:18] <alex_joni> says it works great
[10:45:43] <alex_joni> but he's running puppy installed, so a lightweight distro
[10:54:52] <DanF_DrC> anyone know anyone that have bought this? http://www.team-haase.de/pages/2000_beschreibung.html
[10:55:13] <DanF_DrC> a semi pro table top mill for 2k$
[10:55:31] <DanF_DrC> 600x400x80mm
[10:56:32] <alex_joni> hello DanF_DrC
[10:56:41] <alex_joni> fenn said you want to talk about USB ;)
[10:57:21] <DanF_DrC> I just figured the neatest for PC robotics would be a controller with USB interface. he didn't agree but didn't know why : )
[10:57:39] <fenn> * fenn would like to know too
[10:57:50] <alex_joni> a controller with USB interface might work
[10:58:00] <alex_joni> but the controller needs to do the actual control stuff
[10:58:08] <alex_joni> PID & step-outputs & such
[10:58:21] <fenn> lets use a hexapod as our example
[10:58:25] <alex_joni> such a controller already exists: the G-Rex
[10:58:38] <DanF_DrC> for a CNC mill I would definitely go with waypoint functionality in a controller so there would be no realtime demands on the pc
[10:59:08] <alex_joni> DanF_DrC: why so?
[10:59:28] <alex_joni> fenn: you'd need an external controller that does kins, not likely you'll find one
[10:59:34] <DanF_DrC> so it could handle acceleration etc etc
[10:59:40] <fenn> if i had a self contained external controller i'd use ethernet
[10:59:45] <alex_joni> DanF_DrC: emc2 on a PC does that perfectly
[11:00:00] <fenn> there's even RT ethernet
[11:00:03] <alex_joni> fenn: ethernet or USB .. same sh*t really ;)
[11:00:11] <DanF_DrC> alex_joni, also when the pc hangs for a split second?
[11:00:21] <alex_joni> DanF_DrC: RT-Linux doesn't hang
[11:00:34] <alex_joni> RT being RTLinux or RTAI
[11:01:00] <alex_joni> if you're talking M$ stuff, then all bets are off (I mean software only solution)
[11:01:16] <DanF_DrC> a turned off computer doesn't hang either. I would prefer a platform where actual software exists too
[11:01:36] <alex_joni> DanF_DrC: then how can we help you? this is the #emc channel afterall
[11:01:47] <fenn> can you explain why USB is so bad
[11:02:05] <alex_joni> fenn: USB is good for most applications, RT control it's not
[11:02:25] <alex_joni> fenn: you have about 1msec packet rate
[11:02:58] <alex_joni> so you can only send data every 1msec, even if you send huge packets, that won't help you for your application
[11:03:00] <DanF_DrC> got link for the grex? all products in the world seems to have that name
[11:03:13] <alex_joni> http://www.geckodrive.com/
[11:03:17] <fenn> G-rex is the link i showed you earlier
[11:03:20] <alex_joni> note: not affiliated in any way
[11:03:26] <fenn> G-101 and G-100
[11:03:35] <DanF_DrC> ah yeah. the one with no specs on it
[11:04:01] <DanF_DrC> anyone know the specs?
[11:04:06] <alex_joni> DanF_DrC: there is a group at groups.yahoo.com
[11:04:09] <alex_joni> you can ask in there
[11:04:36] <alex_joni> the specs are on the website I just pasted
[11:04:36] <DanF_DrC> would you agree that there is something wrong when one has to do that?
[11:04:40] <DanF_DrC> where?
[11:04:45] <alex_joni> G101
[11:04:52] <alex_joni> 6-axis step and direction outputs
[11:04:52] <alex_joni> 6 quadrature encoder inputs
[11:04:52] <alex_joni> 16 general purpose outputs
[11:04:52] <alex_joni> 22 general purpose inputs
[11:04:52] <alex_joni> 4 analog outpus
[11:04:55] <alex_joni> 4 analog inputs
[11:04:58] <alex_joni> USB and Ethernet
[11:05:05] <DanF_DrC> ok so the two are the same except for casing?
[11:05:15] <alex_joni> the G101 is inside the G100
[11:05:44] <DanF_DrC> woudln't that just be crazy if they had this info on their site :)
[11:05:52] <fenn> it would be nice
[11:06:13] <alex_joni> I reckon their website isn't the best one I've seen
[11:06:24] <fenn> at least it isn't offensive
[11:06:42] <DanF_DrC> it's clear but grossly lacking
[11:06:45] <alex_joni> DanF_DrC: another option might be to use a PC-based CNC software (like emc) with external Hardware generated pulses
[11:06:52] <fenn> all the info on the yahoo group should be on the website imho
[11:06:54] <DanF_DrC> is the grex pc direct?
[11:07:04] <alex_joni> pc-direct?
[11:07:19] <DanF_DrC> does the pc pulse with the grex
[11:07:46] <fenn> he means does it send g-code or step/dir
[11:08:08] <alex_joni> g-code
[11:08:18] <alex_joni> from the PC to the g-rex you send g-code
[11:08:30] <alex_joni> the g-rex then generates the HW pulses and sends them to the drives
[11:09:00] <alex_joni> not sure it's really g-code you send, but high level movement commands anyways
[11:09:28] <DanF_DrC> ok highlevel. does it support acceleration?
[11:09:39] <alex_joni> it has settings for that
[11:09:59] <alex_joni> but then again, have you EVER seen a software/hardware that doesn't handle acceleration?
[11:10:06] <alex_joni> * alex_joni hasn't
[11:10:17] <DanF_DrC> not bad. what's max steprate? and does it have 8th microstepping
[11:10:32] <alex_joni> the microstepping is in the drive, not in the control
[11:10:40] <alex_joni> max steprate is around 1MHz I think
[11:10:49] <alex_joni> but as they say.. RTFM
[11:11:00] <DanF_DrC> high enough.
[11:11:02] <fenn> g-rex just gives you 5V logic signals
[11:11:14] <DanF_DrC> alex_joni, I've seen pro controllers that didn't do accel right
[11:11:15] <fenn> er, well that's not quite right
[11:12:13] <alex_joni> DanF_DrC: if you want a semi-cheap solution (a good one), I would recommend: http://pico-systems.com/univstep.html
[11:12:22] <DanF_DrC> you probably don't know this but does it have proportional acceleration?
[11:12:27] <alex_joni> that's a hardware step generator, commanded from emc
[11:12:41] <alex_joni> no idea about g-rex internals, only what is on their site, never tried it really
[11:13:02] <DanF_DrC> ok fair enough
[11:13:10] <alex_joni> DanF_DrC: if you want a good machine, then you need servos
[11:13:20] <alex_joni> about 1-2k $ / axis
[11:13:42] <DanF_DrC> at that price I would by a finished machine instead
[11:13:44] <DanF_DrC> buy
[11:13:52] <alex_joni> a toy maybe
[11:14:02] <alex_joni> a real CNC machine is about 50-60k plus
[11:14:16] <DanF_DrC> if you want to mill ships sure :)
[11:14:18] <alex_joni> but then again, it depends on what you expect
[11:14:30] <alex_joni> * alex_joni has seen, touched 1M+ machines
[11:15:09] <alex_joni> so 1-2k/axis is cheap for those
[11:15:24] <DanF_DrC> you can always go more expensive. I can find a cool video clip from one later but let's stay within reason :)
[11:15:38] <alex_joni> DanF_DrC: what do you want to do?
[11:15:47] <DanF_DrC> with the GREX, what motors? any outthere with encoders and not super overpriced?
[11:16:25] <alex_joni> if you want encoders, then the best solution might be the G340 from geck (that's a servo drive with step/dir input, DC motors & encoder feedback)
[11:16:39] <alex_joni> it doesn't work to use encoders on steppers
[11:17:00] <DanF_DrC> hehe then what's the idea with the grex?
[11:17:13] <alex_joni> what do you mean?
[11:17:20] <DanF_DrC> doesn't it support encoders?
[11:17:51] <alex_joni> it seems to, not sure how it handles them though
[11:18:00] <DanF_DrC> carefully I would hope
[11:18:06] <alex_joni> maybe only as position feedback, to ferror if something is wrong
[11:18:22] <DanF_DrC> that would be an obvious use for them :)
[11:18:24] <alex_joni> on servos you have a PID loop to control velocity based on feedback
[11:18:35] <alex_joni> DanF_DrC: it's not at all obvious
[11:18:48] <DanF_DrC> and I'm all for that if only they weren't galactically stupidly overpriced
[11:18:55] <alex_joni> encoders usually are used on servos for feedback, so you know where you are, how fast you went, etc
[11:19:05] <alex_joni> a decent encoder is about 1-200$
[11:19:14] <fenn> oh no!!! not step/dir servos!!!!!!!!
[11:19:14] <DanF_DrC> also a crime
[11:19:15] <alex_joni> wouldn't say that is overpriced
[11:19:23] <alex_joni> fenn: why not?
[11:19:24] <DanF_DrC> I would
[11:19:32] <DanF_DrC> it's a disc with a light on it
[11:19:38] <alex_joni> DanF_DrC: the next time you open one, we'll talk again
[11:19:41] <DanF_DrC> 1$ is a crime
[11:19:52] <alex_joni> DanF_DrC: then build yours and stop whining
[11:20:14] <DanF_DrC> I am but one man and unable to correct the mistakes of the world
[11:20:19] <DanF_DrC> doesn't make them right tho
[11:20:27] <alex_joni> DanF_DrC: whining doesn't help either
[11:20:34] <alex_joni> * alex_joni uses resolvers at work
[11:20:45] <alex_joni> a motor is about 3000$ (AC motor)
[11:20:51] <alex_joni> and I really won't buy a cheaper one
[11:21:07] <DanF_DrC> hehe of course not. why would you
[11:21:10] <alex_joni> that's without the drive and power supply
[11:21:22] <DanF_DrC> and you say that like it was a good thing
[11:21:27] <alex_joni> it is
[11:21:41] <fenn> * fenn doesnt think so
[11:21:42] <alex_joni> sometimes it's better to buy good stuff
[11:21:51] <DanF_DrC> you will excuse me if I fail to see the greatness of a simple electromotor priced like a car
[11:22:02] <fenn> i have $3000 servos that i paid $40 for
[11:22:03] <Imperator_> servos are high precision stuff. the only what you can do is buying a used one at ebay. they have usualy damaged magnets, but good enough for hobby users
[11:22:07] <DanF_DrC> it's possible to do good without overpriced
[11:22:21] <fenn> brand new
[11:22:24] <alex_joni> fenn: lucky you, can you buy that in 300+ quantities?
[11:22:30] <DanF_DrC> and you all think it's reasonable pricing
[11:22:36] <alex_joni> or get one in 12-24h if it fails?
[11:22:51] <fenn> have to pay full price for rush service
[11:23:04] <fenn> that's why i got 7 of them
[11:23:07] <alex_joni> all I'm saying is there are users and users
[11:23:16] <DanF_DrC> maybe you could stock one if it cost 100$ instead
[11:23:44] <alex_joni> some are looking for moderated quality low cost,
[11:23:48] <DanF_DrC> do you have a link for this device?
[11:23:56] <alex_joni> others are looking at high quality, moderated cost
[11:24:03] <fenn> no, it was "the great servo gold rush of 2006"
[11:24:06] <alex_joni> DanF_DrC: which one do you mean?
[11:24:12] <fenn> on surpluscenter.com
[11:24:16] <fenn> no longer there
[11:24:17] <DanF_DrC> the 3000$ ac motor
[11:24:17] <alex_joni> fenn: then you're set ;)
[11:24:58] <alex_joni> fenn: otoh, I sell quite a few robots/year, and I have lots of motor types & drives, I even have most of them on stock (1-2 pcs quantity)
[11:25:21] <alex_joni> but this is industrial stuff, can't mess around
[11:25:21] <fenn> how much is a brand new robot?
[11:25:26] <roltek> morning alex
[11:25:39] <DanF_DrC> alex_joni, the link?
[11:25:39] <alex_joni> fenn: depends on the whole system
[11:25:46] <alex_joni> morning roltek
[11:25:54] <fenn> heh i guess that's like asking "how much does a factory cost"
[11:25:55] <alex_joni> fenn: starts at about 60-70k
[11:26:03] <alex_joni> the smallest ones
[11:26:10] <alex_joni> goes up to.. there's no limit
[11:26:16] <alex_joni> seen 5M+ systems
[11:26:26] <fenn> amazing
[11:26:32] <fenn> where does all the money go?
[11:27:04] <alex_joni> fenn: indeed amazing, 120m X, 20m Y, 7m Z, 3m X', plus the robot
[11:27:16] <alex_joni> with 0.01 mm accuracy overall
[11:27:19] <DanF_DrC> alex_joni, the link?
[11:27:24] <alex_joni> DanF_DrC: what link?
[11:27:33] <DanF_DrC> for the 3000$ ac motor
[11:27:41] <DanF_DrC> as I asked a couple of times now
[11:27:42] <alex_joni> there is no link ;)
[11:28:02] <DanF_DrC> a product with no mention on the web?
[11:28:22] <fenn> industry hates change
[11:28:32] <alex_joni> fenn: it's not that
[11:28:43] <alex_joni> it's just we don't worry about selling the motors
[11:28:51] <alex_joni> we just supply them to our customers
[11:29:02] <DanF_DrC> sprawl
[11:29:04] <alex_joni> so if you buy a robot, you'll get spare motors when they brake
[11:29:15] <alex_joni> you'll have part numbers & all
[11:29:25] <DanF_DrC> do youhave a picture of a robot where it is used then? to get a feel for the size
[11:29:49] <alex_joni> http://www.cloos.de/deutsch/produkte/Kompaktzellen-Anlagen/Bilder_Anlagen/C30_Einsatz_Popup.jpg
[11:30:09] <alex_joni> http://www.cloos.de/deutsch/produkte/Systemloesungen/Branchen/Branchen_64.php
[11:30:31] <alex_joni> http://www.cloos.de/english/produkte/Systemloesungen/Branchen/Branchen.php <-same thing in english
[11:30:33] <DanF_DrC> how heavy is such a 3k$ motor?
[11:31:14] <DanF_DrC> or does it have a wattage spec
[11:31:14] <alex_joni> about 5kg or so. 4kW or so
[11:31:17] <DanF_DrC> k
[11:31:22] <alex_joni> AC 600V
[11:31:28] <fenn> 5kg for a 4kw motor!!
[11:31:28] <alex_joni> but that was just an example
[11:31:38] <fenn> is it water cooled or something?
[11:31:40] <alex_joni> fenn: now you know why they are 3k$
[11:31:45] <DanF_DrC> yep klumsy is prefered in the undustry :)
[11:31:47] <alex_joni> might be 10 :)
[11:32:06] <fenn> DanF_DrC: 4kw is humongous and 5kg is tiny
[11:32:13] <alex_joni> klumsy? think you don't have an idea what 4kW is
[11:32:15] <DanF_DrC> yeah right
[11:32:34] <fenn> * fenn looks at DanF_DrC funny
[11:32:35] <DanF_DrC> 4kw is little more than a common vacuum cleaner motor is what it is
[11:32:40] <alex_joni> fenn: the smaller motors (joint 4-6) are 1kW-ish
[11:32:46] <alex_joni> DanF_DrC: ROFL
[11:32:50] <fenn> DanF_DrC: that is what we refer to as "sears horsepower"
[11:33:03] <DanF_DrC> sigh
[11:33:10] <fenn> its the rating the motor can withstand for a split second before the metal vaporizes
[11:33:14] <DanF_DrC> emperor's new clothes
[11:33:25] <fenn> do the math
[11:33:46] <fenn> 15 amps at 110V is 1.7kw max
[11:34:03] <DanF_DrC> so?
[11:34:16] <fenn> most household circuits have 15A breakers on them
[11:34:26] <K4ts> hello
[11:34:30] <alex_joni> fenn: and that's input power
[11:34:31] <fenn> so there's no way a vacuum cleaner will ever have 4kw
[11:34:41] <K4ts> hi alex_joni
[11:34:48] <alex_joni> hi K4ts
[11:35:01] <DanF_DrC> fenn, no they are usually spec'ed from 1000-2000w
[11:35:17] <DanF_DrC> but doubling it shouldn't make it cost like a car
[11:35:19] <fenn> that rating doesn't mean anything
[11:35:29] <alex_joni> DanF_DrC: just to get you an idea, sold a turn/tilt table recently uses 2 motors 3kW-ish
[11:35:41] <alex_joni> it's for workpieces up to 2500kg
[11:36:11] <fenn> every day i have this painful realization that everything is expensive
[11:36:27] <DanF_DrC> alex_joni, I take it you feel that's a point in itself or is it coming?
[11:36:46] <alex_joni> DanF_DrC: it was a point to help you understand how much power 3kW is
[11:37:06] <DanF_DrC> fenn, no a lot of things are quite cheap. but the nano is it 'business to business' all reason get lost
[11:37:11] <alex_joni> I thought 5000 pounds might be more perceptible to you
[11:37:43] <DanF_DrC> alex_joni, hehe ok
[11:37:55] <DanF_DrC> monstroously stupid but ok
[11:40:03] <fenn> * fenn goes to bed
[11:40:04] <DanF_DrC> IBM once sold 486s for 15k$ while clones of the same specs were sold for 1/5th
[11:40:19] <DanF_DrC> you let status quo dictate your beliefs and it doesn't impress me
[11:40:42] <alex_joni> DanF_DrC: again, it depends on what you want to accomplish
[11:40:46] <DanF_DrC> wrong
[11:40:55] <DanF_DrC> it has nothing to do with quality
[11:41:02] <DanF_DrC> overpriced is overpriced
[11:41:02] <alex_joni> no, I didn't say quality
[11:41:08] <DanF_DrC> then what?
[11:41:10] <alex_joni> I said what you want to accomplish
[11:41:17] <alex_joni> do you want to cut cardboard?
[11:41:23] <DanF_DrC> sigh
[11:41:25] <DanF_DrC> never mind
[11:41:28] <alex_joni> or do you want to cut steel at 1200IPM ?
[11:41:40] <DanF_DrC> that would be quality or specs
[11:41:50] <DanF_DrC> overpriced means overpriced
[11:42:09] <alex_joni> overpriced can be overpriced if you have where to chose from
[11:42:14] <DanF_DrC> like the ibm's of yesteryear
[11:42:30] <DanF_DrC> alex_joni ?
[11:42:41] <DanF_DrC> that sentence didn't make sense
[11:42:43] <alex_joni> say you are a big factory
[11:42:53] <DanF_DrC> please not a long story
[11:42:54] <alex_joni> you have certain contracts with your clients
[11:43:16] <alex_joni> and you have something like a few k$ for every hour downtime
[11:43:39] <DanF_DrC> you just don't get it. you desperately want the prices to be reasonable
[11:43:55] <alex_joni> not sure I follow your thoughts?
[11:44:13] <alex_joni> what do you want? a 3k motor to cost 100$ ?
[11:44:25] <DanF_DrC> what if it cost 100k$ for that motor? or a million. when would it be overpriced?
[11:44:32] <DanF_DrC> that's what I want yes
[11:44:37] <alex_joni> when I can get a cheaper one
[11:44:44] <DanF_DrC> and it should weigh 1/10th
[11:44:48] <alex_joni> with the same specs, or maybe comparable
[11:45:14] <fenn> * fenn gives DanF_DrC some superconducting wire
[11:45:14] <DanF_DrC> that's another aspect. I am not saying that you can find it cheaper anywhere else. that doesn't make the price reasonable
[11:45:41] <alex_joni> DanF_DrC: there are lots of motor suppliers out there
[11:45:53] <alex_joni> don't you think ONE of them would make a cheaper motor if they could?
[11:46:01] <DanF_DrC> no
[11:46:07] <alex_joni> and I don't mean 2.5k instead of 3k
[11:46:13] <DanF_DrC> nor do I
[11:46:38] <alex_joni> why not?
[11:46:39] <DanF_DrC> it's a phenomenon onto itself how these overpriced things can keep in business
[11:47:00] <alex_joni> did you study some economy?
[11:47:34] <alex_joni> lets take stepper drivers for example
[11:47:36] <DanF_DrC> not formally no
[11:47:43] <alex_joni> the gecko G320 is about 100$ or so
[11:47:55] <alex_joni> you can build your own L297/L298 for about 20$
[11:48:08] <alex_joni> which of these is overpriced?
[11:48:15] <alex_joni> * alex_joni says none
[11:48:24] <alex_joni> they both are worth their money
[11:48:54] <alex_joni> I meant G201
[11:49:01] <alex_joni> http://www.geckodrive.com/product.cfm?pid=11
[11:49:34] <alex_joni> lots of people will say 140$ (I just looked) for a simple stepper driver (even if it does microstepping) is way too much
[11:49:44] <DanF_DrC> I don't care for the concept 'worth their money'
[11:49:54] <DanF_DrC> so is the 3k$ ac motor
[11:50:10] <DanF_DrC> to some who can drown that massive overprice in other massive overprices
[11:50:13] <alex_joni> DanF_DrC: then simply don't buy it.. it's a free world
[11:50:21] <DanF_DrC> hardly :)
[11:50:31] <alex_joni> you have the choice of not buying it
[11:50:46] <DanF_DrC> obviously
[11:50:55] <alex_joni> and why don't you care for the concept 'worth their money' ?
[11:51:04] <alex_joni> don't you care how you spend your money?
[11:51:15] <alex_joni> or do you evaluate by amount only?
[11:51:25] <DanF_DrC> I evaluate by reason
[11:51:48] <DanF_DrC> like a small ac motor shouldn't cost as much as a full featured car
[11:51:55] <DanF_DrC> quite simple
[11:52:00] <DanF_DrC> only tunnel vision can't see that
[11:52:18] <alex_joni> 1. it's not a small motor (it's a very big one by very many standards)
[11:52:28] <alex_joni> 2. a full featured car is more like 10k
[11:52:44] <DanF_DrC> there are chinese cars for 3k$ now
[11:53:04] <DanF_DrC> if you like I can see if I can find a link
[11:53:26] <DanF_DrC> but I think I would just be wasting my effort trying to convince you
[11:53:49] <alex_joni> no, we have <5k$ new cars over here
[11:53:57] <alex_joni> but I wouldn't dream of buyng one
[11:54:18] <DanF_DrC> of course that doesn't void the point in any way
[11:54:24] <alex_joni> btw, http://www.baldor.com/products/servomotors/n_series/bsm_nseries.asp
[11:54:37] <alex_joni> it's just that I think 5k on a car like that is wasted money
[11:54:47] <alex_joni> it's cheap, yes, but it's very bad
[11:54:58] <alex_joni> so it's not worth it, or you might say it's overpriced
[11:54:58] <DanF_DrC> that's the motor?
[11:55:05] <alex_joni> similar
[11:55:20] <DanF_DrC> wow that statement disgusts me a lot
[11:55:32] <alex_joni> which one?
[11:55:48] <DanF_DrC> that you would call a 3k$ car overpriced but that pos motor for the same price reasonable
[11:56:05] <alex_joni> it's a different thing, that's what I am trying to explain to you
[11:56:11] <alex_joni> I personally wouldn't buy either
[11:56:15] <DanF_DrC> no shit sherlock
[11:56:17] <alex_joni> the car is simply bad
[11:56:21] <alex_joni> the motor is of no use to me
[11:56:46] <alex_joni> but for people who need such motors, they are glad to buy them
[11:57:05] <alex_joni> you're generalizing your views on the world, that's your problem
[11:58:09] <fenn> i find it interesting that the motor page doesnt list horsepower anywhere
[11:58:23] <alex_joni> fenn: that depends on power supply, it says max amps
[11:58:34] <alex_joni> so if you use it at 600V you can calc. your kW
[11:58:45] <alex_joni> check performance graph
[11:58:46] <fenn> yes, but horsepower is usually used as a marketing tool
[11:59:03] <fenn> so it means people who are buying it are going on specifications alone
[11:59:17] <fenn> and brand loyalty/company reputation
[11:59:22] <alex_joni> fenn: normal people don't buy these motors
[11:59:58] <alex_joni> it's rather system designers who decide, and they try quite a few out before they say that is the motor we'll use
[12:00:28] <alex_joni> and baldor happily will provide lots of motors for testing for a robot company
[12:00:41] <alex_joni> s/baldor/motor supplier/
[12:02:01] <alex_joni> but I agree that this is all 2-3 levels above the home user trying to fit a machine together
[12:02:18] <fenn> it is a pain in my ass for sure
[12:02:27] <alex_joni> fenn: why?
[12:02:41] <fenn> all the RFQ stuff for one
[12:02:50] <fenn> baldor actually lists prices, which is weird
[12:02:55] <alex_joni> fenn: RFQ ?
[12:02:58] <fenn> request for quote
[12:03:17] <alex_joni> fenn: that's a strange ideology
[12:03:22] <alex_joni> I give you that
[12:03:24] <DanF_DrC> RFQ means ashamed at the price
[12:03:30] <fenn> hard to make intelligent decisions when you have to wait a couple days and mail 20 different companies
[12:03:32] <alex_joni> but there are various reasons for that
[12:03:46] <alex_joni> DanF_DrC: that's #1 reason
[12:03:49] <fenn> i dont understand why digikey can list prices but company xyz cant
[12:04:12] <alex_joni> fenn: I don't know about others, but I know why I don't list prices on my site
[12:04:15] <fenn> in fact digikey is my hero
[12:04:23] <alex_joni> and that is because _my_ users are ignorant
[12:04:24] <DanF_DrC> the lie has to linger long enough for some to believe the price is reasonable
[12:04:31] <alex_joni> they don't really know what they need
[12:04:45] <DanF_DrC> humans are such fools
[12:04:57] <DanF_DrC> ah well
[12:05:24] <anonimasu> *yawn*
[12:05:32] <alex_joni> morning anders
[12:05:41] <fenn> alex_joni: so you're saying people will choose the lowest price and then bitch about it not doing what they want?
[12:05:44] <anonimasu> morning
[12:05:49] <alex_joni> fenn: usually yes
[12:05:55] <anonimasu> * anonimasu has finally almost finished cleaning
[12:06:04] <anonimasu> I find that to be true
[12:06:07] <alex_joni> fenn: err, make that always
[12:06:36] <alex_joni> because, at least in my case, most of the decision factors have nfc about what the needed specs are
[12:07:15] <alex_joni> I mean when a big company buys some stuff, it's usually some manager who gets the decision
[12:07:21] <alex_joni> and he's a technical moron usually
[12:07:34] <anonimasu> the company I buy stuff off is the same with..
[12:07:53] <DanF_DrC> alex_joni, what kind of gearing is inside such a robot using such a motor?
[12:08:08] <alex_joni> DanF_DrC: lots of different types
[12:08:14] <alex_joni> depending on the joints
[12:08:23] <DanF_DrC> sure but give an example
[12:08:30] <anonimasu> inertia matching..
[12:08:44] <alex_joni> not sure how they are called in english, sorry it's not my native language
[12:08:57] <robin__> meep?
[12:09:00] <alex_joni> hi robin
[12:09:03] <anonimasu> DanF_DrC: google for it.. :)
[12:09:04] <robin__> dood!
[12:09:05] <anonimasu> hey robin
[12:09:25] <DanF_DrC> anonimasu, I'll bet you 10$ you can't find it with google
[12:09:32] <DanF_DrC> alex_joni, gear ratio
[12:09:38] <anonimasu> inertia matching of motors?
[12:09:43] <alex_joni> 1:20 or so
[12:09:47] <DanF_DrC> ok
[12:09:55] <DanF_DrC> thanks
[12:10:06] <anonimasu> I could bet you 50 that it's on google..
[12:10:10] <anonimasu> http://www.google.se/search?hl=sv&q=inertia+matching&btnG=Google-s%C3%B6kning&meta=
[12:10:14] <alex_joni> of course they are backlash free
[12:10:31] <DanF_DrC> no doubt it's good engineering
[12:10:54] <fenn> betting against google is usually a bad idea i've found
[12:11:04] <alex_joni> DanF_DrC: and good engineering tends to have its price :)
[12:11:09] <anonimasu> the rotor inertia is what makes servos cheap/expensive..
[12:11:12] <DanF_DrC> anonimasu, I never asked for any inertia matching
[12:11:29] <alex_joni> DanF_DrC: but that is used to calc. the gear ratio
[12:11:44] <alex_joni> DanF_DrC: never figured out why the engineers are overpriced like that .. lol
[12:12:02] <DanF_DrC> alex_joni, there is no doubt it has a price
[12:12:17] <fenn> DanF_DrC: some robots have helical gears, some have ballscrews, some have timing belts, some have linear actuators
[12:12:37] <DanF_DrC> fenn, obviously
[12:12:38] <alex_joni> most ours have helical
[12:12:43] <fenn> worm gears arent so common
[12:13:11] <fenn> DanF_DrC: ever made a gear?
[12:13:20] <fenn> * fenn hasn't
[12:13:33] <fenn> i'm gonna have to though because i cant find the ones i need
[12:13:38] <alex_joni> fenn: normal gears are simple enough to make
[12:13:47] <DanF_DrC> fenn, no havne't
[12:14:45] <DanF_DrC> do you have the equip to do it?
[12:15:13] <alex_joni> fenn: even work gears have been used on robots (low power motors)
[12:15:25] <fenn> work gears?
[12:15:32] <alex_joni> worm
[12:15:34] <alex_joni> sorry
[12:15:37] <DanF_DrC> worm is often used in drills
[12:15:48] <fenn> drills are usualy planetary
[12:16:04] <DanF_DrC> ah yes I confused the two
[12:16:11] <fenn> so-called "worm drive" circular saws actually use cycloidal gearing
[12:16:55] <fenn> DanF_DrC: i have to make some fixtures, but yeah i have a lathe
[12:17:09] <fenn> (which i built from melted down scrap btw)
[12:17:27] <DanF_DrC> a lathe can stop at intervals?
[12:17:41] <alex_joni> DanF_DrC: it doesn't have to
[12:17:41] <fenn> yeah if you stop turning the handle :)
[12:17:56] <fenn> gear hobbing is a continuous process
[12:18:00] <DanF_DrC> how are the teeth done then?
[12:18:04] <alex_joni> usually gear get cut with special tooling, linked to the spindle speed
[12:18:14] <fenn> you know how a worm gear works right?
[12:18:29] <DanF_DrC> sure
[12:18:30] <fenn> if you traverse the worm across the gear face as its cutting it will make gear teeth
[12:18:30] <robin__> gear hobs are simple .. but ingenious
[12:18:48] <fenn> i dont get why people use those form cutters.. such a bad idea
[12:18:59] <alex_joni> http://www.superior-ny.com/Superior-NY/Web%20Images/DSCN0028.JPG
[12:19:47] <robin__> a gear hob will cut the correct tooth for for multiple numbers of teeth on a pnion, fromt he same form cutter
[12:19:55] <DanF_DrC> how does that ensure even spacing when it closes at the back?
[12:20:40] <robin__> its neat how it gets the undercut correct on pinions with small diameters
[12:20:50] <robin__> * robin__ shuts up
[12:21:04] <fenn> robin__: i've got a question for you, along the same lines as this conversation actually
[12:21:12] <fenn> how come you need a laser to do lasercutting?
[12:21:12] <robin__> uh huh?
[12:21:26] <robin__> fenn, well, how else would you fo it?
[12:21:28] <fenn> why not use focused IR radiation from a blackbody
[12:21:33] <DanF_DrC> fenn, how does it ensure it fits when it comes round?
[12:21:38] <robin__> ummm ...
[12:21:42] <alex_joni> http://www.emachineshop.com/machines/Spur-gear-cutting.htm
[12:21:48] <fenn> DanF_DrC: you need to make the blank the correct diameter to start with
[12:21:55] <robin__> thats the same as "why not just use a very bright bulb"
[12:22:08] <fenn> yeah why doesnt it work
[12:22:16] <robin__> because its non-coherent
[12:22:20] <fenn> so what?
[12:22:29] <robin__> so you cant focus it on a tiny spot
[12:22:42] <fenn> how tiny does it have to be?
[12:22:51] <robin__> 0.2mm or less
[12:23:15] <DanF_DrC> you want to do a laser cutter without a laser?
[12:23:20] <fenn> yeah
[12:23:30] <fenn> or at least etching
[12:23:38] <robin__> good luck ... :)
[12:23:44] <DanF_DrC> could probably be done. might not be easier to
[12:23:45] <DanF_DrC> tho
[12:23:54] <alex_joni> fenn: you might get away with a big magnifying glass and the sun
[12:23:55] <robin__> you need to exceed the dmage threshold of the substrate
[12:24:13] <alex_joni> but you'd be etching away at 0.001mm/sec
[12:24:14] <fenn> i'm thinking high-wattage heaters cost less than hi-wattage lasers
[12:24:15] <alex_joni> or less :D
[12:24:30] <robin__> well, yeah, but non-coherent
[12:24:32] <alex_joni> fenn: compare the input powers, not outputs
[12:24:40] <fenn> robin__: does the pulsing action of the laser have an effect?
[12:24:51] <alex_joni> fenn: it does have a very BIG effect
[12:24:52] <robin__> pulsing?
[12:24:58] <fenn> i read about military lasers waiting for the puff of gas to clear the hole before firing again
[12:25:00] <robin__> we have no pulsing
[12:25:12] <alex_joni> robin__: some smaller powered YAG's have pulsing
[12:25:17] <fenn> like a couple ms
[12:25:22] <alex_joni> seen a tiny 150W, with 2.5kW pulses
[12:25:22] <robin__> oh flea power ones yeah
[12:25:35] <alex_joni> Trumpf though
[12:25:42] <robin__> you can pulse them, mines CW
[12:25:56] <fenn> so pulsing doesnt improve the cutting action?
[12:25:59] <robin__> and yeah, its a trumpf
[12:26:02] <robin__> do.
[12:26:04] <robin__> no
[12:26:11] <robin__> no pulsing makes it worse ..
[12:26:23] <robin__> some roots-blower type gas lasers pulse a bit ...
[12:26:29] <alex_joni> later guys
[12:26:32] <fenn> alright.. next question..
[12:26:33] <DanF_DrC> cya
[12:26:48] <robin__> if you have low power, and need to do stuff, pulsing (as in Q swtitching) can help
[12:26:55] <fenn> how do you get square edges? or do you?
[12:27:04] <fenn> and what is the focal length of the lens
[12:27:07] <robin__> lots of the etchers/markers are pulsed I think ...
[12:27:21] <robin__> I do getg sq edges ..
[12:27:33] <robin__> fl is around 6"
[12:27:43] <fenn> how big around is the lens?
[12:27:50] <robin__> 38mm
[12:28:06] <robin__> but only the centre 12mm or so is illuminated
[12:28:14] <fenn> ok so that triangle has tan(30mm/6")
[12:28:24] <fenn> er tan(12mm/6")
[12:28:30] <robin__> you can get lenses from places like laser II VI
[12:28:50] <fenn> say you are cutting a piece of plexi 1 inch thick
[12:28:58] <robin__> 1" ...
[12:29:03] <robin__> err ...
[12:29:13] <fenn> so the spot is 2mm in dia at the top of the plexi
[12:29:15] <fenn> right?
[12:29:21] <fenn> if its focused on the bottom
[12:29:28] <fenn> or 1mm on top, focused in middle, 1mm on bottom
[12:29:34] <robin__> ummm ... 1" ... you might be in trouble
[12:29:44] <robin__> for YAG you focus on the top
[12:29:56] <DanF_DrC> at what distance?
[12:29:57] <robin__> for CO2, just below the surface
[12:30:17] <robin__> you'll need co2 for plexi, yag ignores it
[12:30:39] <fenn> ah that's the other problem with lasers, you can't change the wavelength
[12:30:54] <robin__> well, co2 works on most stuff
[12:30:55] <DanF_DrC> not entirely true
[12:31:07] <robin__> you can if the lasing medium is multiline
[12:31:22] <robin__> like my argon lasers
[12:31:33] <DanF_DrC> you cut at 6" distance?
[12:31:38] <robin__> the back mirror is via a prism
[12:31:51] <robin__> from the lens to the workpiece, yes
[12:32:19] <robin__> there is a nozzle at 6" from the lens, sits 0.7mm above the workpiece
[12:32:21] <DanF_DrC> ok that would give close to square then
[12:32:31] <robin__> well, it gives sq
[12:32:45] <robin__> there is a waveguide effect of the molten steel
[12:32:50] <fenn> the nozzle just keeps spatter off the lense and keeps the work from oxidizing right?
[12:33:03] <fenn> or oxidizes it if you are doing steel
[12:33:08] <DanF_DrC> and eyes from stopping working
[12:33:13] <robin__> mmm .. the nozzle direct a stream of oxygen or nitrogen into the cut
[12:33:33] <robin__> about 2bar of 02 for steel
[12:33:44] <DanF_DrC> robin__, completely square it probably isn't
[12:33:46] <robin__> or 12bar of N2 for stainless and aluminium
[12:34:07] <robin__> DanF_DrC, better than 0.5degree in thin stuff
[12:34:24] <fenn> how wide is the kerf for say 1mm sheet
[12:34:26] <DanF_DrC> what is thin?
[12:34:32] <robin__> thin is 5mm and under
[12:34:37] <DanF_DrC> ok
[12:34:39] <robin__> 1mm? 0.3mm kerf
[12:34:59] <robin__> about 0.4mm kerf at 5mm
[12:35:11] <fenn> can you cut steel at all without using O2?
[12:35:16] <robin__> no
[12:35:16] <DanF_DrC> fenn, like the motors, lasers are not expensive because they have to be
[12:35:24] <anonimasu> LOLO
[12:35:28] <anonimasu> err LOL
[12:35:36] <DanF_DrC> a 10kw lightbulb cutter would cost a lot too
[12:35:44] <robin__> but it wouldnt work
[12:35:55] <fenn> i dont get why it wouldnt work
[12:36:08] <DanF_DrC> robin__, of course it would
[12:36:11] <robin__> you couldnt focus it onto a small spot ...
[12:36:13] <fenn> if you have the energy coming from a point source
[12:36:21] <robin__> sigh ...
[12:36:24] <robin__> poitn source?
[12:36:28] <DanF_DrC> sigh all you want
[12:36:30] <fenn> ok lets say you're focusing light from the sun
[12:36:32] <robin__> that would be WORSE
[12:36:35] <anonimasu> fenn: why dont you just cut with electrons?
[12:36:35] <fenn> perfectly parallel rays
[12:36:35] <robin__> ok,
[12:36:45] <anonimasu> fenn: what kind of lightsource is that?
[12:36:47] <fenn> anonimasu: vacuum pump is too big and crappy
[12:37:06] <robin__> fenn perfectly parralel rays on multiple frequencies .. OK, keep going
[12:37:08] <fenn> ok sunlight through lense onto steel
[12:37:27] <DanF_DrC> sunlight??
[12:37:33] <fenn> you're floating in outer space so you dont have to worry about the earth tilting or anything
[12:37:41] <fenn> can you cut through steel with that light?
[12:37:55] <robin__> not easily ...
[12:37:57] <DanF_DrC> the sun has a significant size that would hamper focusing
[12:38:01] <fenn> with o2 assist
[12:38:10] <robin__> no that would aid focussing
[12:38:11] <fenn> DanF_DrC: silence you
[12:38:40] <fenn> scenario 2, you use a mirror to focus the sun onto a spot
[12:38:41] <robin__> remember a bigger lens can focus to a small er spot
[12:39:03] <fenn> no more chromatic abberation
[12:39:46] <fenn> why wouldn't that work?
[12:40:06] <robin__> well, you cant get it into a small spot
[12:40:10] <fenn> why no?
[12:40:15] <robin__> think of it like waves
[12:40:34] <fenn> wavelength of IR is like 1000nm
[12:40:37] <robin__> the ocean waves have lots of energy right?
[12:40:57] <robin__> try to combine all the energy of a whole beach into one spot ...
[12:41:10] <robin__> stuff will start to cancel out
[12:41:14] <DanF_DrC> robin__, that was an unusually bad example :)
[12:41:46] <robin__> well, yeah
[12:41:56] <fenn> it will do destructive interference in some places and constructive in others
[12:42:00] <DanF_DrC> besides some tsunamies are focused fairly well
[12:42:10] <anonimasu> eh?
[12:42:18] <fenn> nah that's just raw power
[12:42:22] <anonimasu> waves propagate..
[12:42:30] <robin__> photons do not just "add up" regardless .. you need coherence for tiny spots to be effective
[12:42:49] <anonimasu> if you have enough power they'll be destructive.. but it's still not pointed..
[12:42:53] <robin__> this is also why you need circular polarization of the beam
[12:42:54] <DanF_DrC> fenn, you will find that depending on coast shape some regions are not affected while others are wasted
[12:43:13] <robin__> linearly polarised lasers are no use for cutting
[12:43:23] <robin__> they cut well in one directiom crap in another
[12:43:40] <fenn> hmm i've never heard that before
[12:43:43] <robin__> all industrial lasers have a lamda/8 delay and a splitter
[12:44:17] <robin__> serch for co2 phase retarder
[12:45:06] <DanF_DrC> since you can cut paper with sun it's a simple matter of increasing power. it might not in any way be as good or even practical but surely can be done
[12:45:34] <anonimasu> are you cutting the papaer really?
[12:45:47] <anonimasu> or are you just heating it up to the flaming point of the material?
[12:45:48] <robin__> possibly .. with a field of huge mirrors ... and if you didnt mind a kerf wdth of 2mm plus
[12:46:01] <fenn> haha i love it
[12:46:12] <fenn> DanF_DrC: no you cannot cut paper that's the answer :P
[12:46:21] <robin__> my laser has 30Kw of arc lamps in it :)
[12:46:25] <anonimasu> paper dosent catch fire when you cut it with a laser isnt that right?
[12:46:36] <robin__> well, it does, locally,
[12:46:37] <fenn> thats cause there's a nitrogen jet blowing onit
[12:46:49] <robin__> ummm . compressed air ususally for paper
[12:46:57] <DanF_DrC> anonimasu, at 2000degrees even steel is impressed
[12:48:38] <fenn> i am thinking a telescope mirror made out of SiC and heated to 1000C or so
[12:48:41] <DanF_DrC> but lasers no doubt has significant advantages
[12:48:59] <DanF_DrC> woot? : ) why would you heat the mirror?
[12:49:06] <fenn> or if that's no good, a mirror and a spherical blackbody
[12:49:18] <fenn> heating the mirror is simpler
[12:49:28] <fenn> otherwise i'd have to cool the mirror :)
[12:49:35] <fenn> and that's no good
[12:50:09] <DanF_DrC> you want to cut with the blackbody rad from a large mirror?
[12:50:21] <fenn> yeah
[12:50:27] <DanF_DrC> hehe why?? : )
[12:50:34] <fenn> to get rid of the laser silly
[12:50:38] <DanF_DrC> why not a potent lamp? like a fusion light
[12:50:46] <fenn> a what??
[12:50:55] <DanF_DrC> they just call it that
[12:51:08] <robin__> look just buy my 450w co2 and be happy :)
[12:51:08] <robin__> �1000 and its yours :)
[12:51:11] <robin__> complete with 2 psus, vac pumps, controller box thing, cutting torch and spare glassware
[12:51:12] <anonimasu> are you sure thoose methods are feasible at all compared to a real laser?
[12:51:12] <DanF_DrC> something like a microwave driven gas light
[12:51:14] <robin__> * robin__ waits for any takers
[12:51:18] <robin__> look just buy my 450w co2 and be happy :)
[12:51:21] <robin__> complete with 2 psus, vac pumps, controller box thing, cutting torch and spare glassware
[12:51:23] <robin__> �1000 and its yours :)
[12:51:25] <fenn> anonimasu: no i have no idea
[12:51:28] <robin__> no takers?
[12:51:29] <fenn> robin__: thats pretty cheap
[12:51:43] <fenn> shippings a bitch tho
[12:51:47] <robin__> sold to the man!
[12:51:50] <Jymmm> robin__ free shipping and it's a deal
[12:51:54] <robin__> nah :)
[12:52:05] <robin__> weight is close to 800kg
[12:52:10] <DanF_DrC> do you have one in hand held robin__ : )
[12:52:10] <fenn> i'll buy it if you can store it long enough for me to sell it :)
[12:52:12] <Jymmm> robin__ 450w... damn, that's 220
[12:52:34] <robin__> thats the problem ...
[12:52:41] <fenn> DanF_DrC: a maser wouldnt have a tight enough spot because microwaves are so big
[12:52:57] <robin__> moving factory next week, need to clear it really
[12:53:08] <Jymmm> robin__: laser or complete laser engraver/cutter?
[12:53:26] <DanF_DrC> fenn, but a large mirror has a tight enough spot?
[12:53:28] <fenn> 450W would cut metal
[12:53:40] <robin__> just the laser ... I have the motion system too, complete with bed for another �1000 :)
[12:53:42] <fenn> DanF_DrC: yeah but i'm using IR radiation not microwave
[12:54:04] <anonimasu> robin__: do you have a control?
[12:54:05] <anonimasu> ^_^
[12:54:23] <DanF_DrC> fenn, you could power it with 1mm radiation
[12:54:32] <fenn> ok
[12:54:33] <robin__> http://www.hw.ac.uk/mecWWW/amu/amu9.jpg
[12:54:34] <DanF_DrC> and you can have effects smaller than wavelenght
[12:54:38] <robin__> liek that ....
[12:55:02] <anonimasu> sweet
[12:55:11] <robin__> the PSU is the big box back right
[12:55:14] <fenn> that sure looks nice
[12:55:19] <fenn> is yours as pretty as that one
[12:55:20] <robin__> I have two ... one and a spare
[12:55:27] <robin__> mmm ... not quite as pretty
[12:55:38] <robin__> I started photoing it for ebay
[12:56:03] <DanF_DrC> how much power does it take to get the 450w?
[12:56:16] <robin__> not in one piece and working ... but all there
[12:56:17] <Jymmm> 250mA
[12:56:35] <robin__> 450W, about 15kw input
[12:56:44] <DanF_DrC> hehe
[12:56:44] <robin__> maybe 12Kw ...
[12:57:03] <robin__> my 700W yag takes 30Kw so its not bad
[12:57:13] <DanF_DrC> they shoud aim for around 100% efficient instead
[12:57:42] <DanF_DrC> or more when they are at it
[12:58:10] <DanF_DrC> robin__, what is it that you do? sell them?
[12:59:23] <fenn> heh you really want a fusion light huh
[12:59:42] <fenn> deuterium/tritium laser
[12:59:56] <fenn> that'd be sweet
[13:00:09] <DanF_DrC> naw, better than that
[13:00:32] <fenn> brown's gas torch
[13:00:41] <fenn> umm.. mind over matter
[13:00:50] <fenn> reality engineering device
[13:00:51] <robin__> DanF_DrC, nah, I run a subcontract laser cutting company ... I seem to acquire old lasers like other people acquire old pcs
[13:00:53] <DanF_DrC> a device that just asks the universe to deliver a given laser intensity
[13:01:00] <DanF_DrC> no energy required
[13:01:18] <fenn> DanF_DrC: that's no fun
[13:01:29] <anonimasu> maybe you should stop drinking now
[13:01:40] <DanF_DrC> when you see the beam streaming from a hand held device you will think it is fun :)
[13:01:52] <robin__> DanF_DrC, http://www.rapidcut.co.uk/
[13:01:57] <fenn> why do you need a hand held device?
[13:02:02] <robin__> death ray!
[13:02:07] <fenn> real men shoot lasers from their eyeballs
[13:02:10] <alex_joni> fenn: so he can cut crappy with it ;)
[13:02:30] <DanF_DrC> robin__, any competition for the lasers? magnetic cutting or something?
[13:03:03] <DanF_DrC> or is lasers the thing for now
[13:03:25] <fenn> plasma, waterjet, edm
[13:03:36] <fenn> electron beam machining
[13:03:53] <fenn> tons of stuff
[13:04:00] <fenn> then you have all the mechanical processes
[13:04:17] <fenn> what kind of crazy people use lasers to cut metal?!
[13:04:23] <robin__> plasma is the only real one .. and its crap :)
[13:04:25] <DanF_DrC> I was just thinking it was foolish to heat the metal up since it's just a plane of bonds you want loosened
[13:04:33] <robin__> waterjet is slow ...
[13:04:40] <robin__> edm is galcial
[13:04:44] <DanF_DrC> anyone know the principle in plasma?
[13:04:50] <robin__> sure ...
[13:04:56] <anonimasu> isnt waterjet pretty fast nowdays
[13:04:57] <DanF_DrC> just electrical?
[13:05:00] <anonimasu> yeah
[13:05:00] <fenn> yeah an electric arc heats up a compressed air stream, ionizing it into a plasma
[13:05:11] <robin__> sorta
[13:05:15] <DanF_DrC> so a tazer more of less : )
[13:05:19] <fenn> the plasma goes through a spiral-shaped nozzle and begins to rotate,
[13:05:31] <DanF_DrC> indeed
[13:05:32] <fenn> the rotation creates a magnetic field which causes the plasma to contract into a tight stream
[13:05:49] <fenn> that's my understanding of it
[13:05:57] <robin__> the plasma is intially struck between the nozzle and electrode ...
[13:06:02] <DanF_DrC> hmm one would think that guiding plasma could be hazardous
[13:06:08] <robin__> then the arc is transferred to the workpiece
[13:06:19] <robin__> DanF_DrC, well spotted
[13:06:29] <robin__> DanF_DrC, one fuck up and your nozzel is toasted
[13:06:36] <DanF_DrC> transfered how? just inertia?
[13:06:45] <robin__> electrically
[13:06:51] <fenn> its blown out by compressed air
[13:07:01] <robin__> the circuit to the nozzel os brokemn and the one to the workpiece is made
[13:07:10] <robin__> and there is the airflow ...
[13:07:14] <DanF_DrC> yeah but you can't blow it out since the walls would be damaged
[13:07:19] <fenn> the workpiece is grounded, and the initial arc starter in the nozzle is grounded too
[13:07:31] <DanF_DrC> ah ok
[13:07:36] <fenn> DanF_DrC: the nozzle is made of high temp ceramic
[13:07:46] <DanF_DrC> fenn, that wouldn't help :)
[13:07:47] <robin__> but the nozzel is isilated during cutting
[13:07:54] <DanF_DrC> the beam is 30k
[13:07:54] <robin__> fenn, no, it copper
[13:07:56] <anonimasu> I've never seen that-..
[13:08:02] <anonimasu> as robin said it's copper..
[13:08:07] <fenn> hmm the one i used was ceramic
[13:08:15] <robin__> I used to sell plasma systems ...
[13:08:17] <anonimasu> the thing that protect the nozzle is plastic..
[13:08:36] <fenn> looked like a pasta noodle kinda
[13:08:43] <robin__> we made more money on the large quantities of nozzels than on the systems :)
[13:08:45] <fenn> deep square threads
[13:09:12] <anonimasu> robin__: piercing with plasma/not tilting the torch isnt to good
[13:09:13] <anonimasu> :)
[13:09:27] <DanF_DrC> robin__, so all the electrons are kept at the gun? and only the positive cores are sent out?
[13:09:28] <robin__> anonimasu, all the CNC systems pierce straight
[13:09:37] <anonimasu> hm, really?
[13:09:46] <robin__> anonimasu, yep
[13:09:51] <anonimasu> robin__: might be why they eat nozzles..
[13:09:53] <fenn> they change torch height for piercing right?
[13:10:02] <robin__> fenn, yes they do
[13:10:09] <les_w> morning
[13:10:22] <fenn> oh well if it isnt mister capitalist himself
[13:10:24] <robin__> pierce height is fixed .. then after that it varies to maintain a constant arc voltage during the cut
[13:10:27] <les_w> hahaha
[13:10:37] <robin__> hey rich boy! ;)
[13:10:38] <anonimasu> robin__: nozzles last forever if you dont blow the melted metal back into them
[13:11:05] <robin__> anonimasu, to an extent ... true. they get a bit crappy from the initial arc process
[13:11:12] <anonimasu> yep
[13:11:29] <robin__> Hypertherm are the guys to see about that
[13:12:12] <anonimasu> ?
[13:12:33] <robin__> they claim up to 800 starts from a single electrode ...
[13:12:37] <DanF_DrC> robin__, one thing you might now, has the lasers gotten a lot smaller over the years?
[13:12:44] <les_w> I wanted to visit miller /hobart and try plasma on my trip but got too busy with other stuff
[13:13:44] <robin__> DanF_DrC, soemwhat, yes. solidstate lasers are a bit smaller I guess ... lots of diodes pointing at a YAG rod, and disc lasers are good for their size .. but there is no benefit really from small size
[13:14:00] <robin__> indistrially, space is not aproblem
[13:14:09] <DanF_DrC> price is however
[13:14:24] <DanF_DrC> price has gone down too no?
[13:14:24] <robin__> smaller != cheaper
[13:14:31] <robin__> not really, no
[13:14:45] <DanF_DrC> hmm, should have
[13:15:05] <DanF_DrC> my 4$ 5mw laser certainly would have cost more 20 years ago
[13:15:20] <robin__> sure .. but thats because they sell millions now
[13:15:34] <robin__> the market for multi-kilowatt lasers is still small
[13:15:45] <les_w> I was messing with a 50w diode pumped yag a friend bought
[13:15:46] <DanF_DrC> sure but same solid state tech used in yours I would imagine
[13:15:58] <Jymmm> 35W CO2 12" x 24" == $15,000 USD
[13:15:59] <les_w> wants to start a marking business his wife can run
[13:15:59] <robin__> DanF_DrC, nah ...
[13:16:17] <Jymmm> wife?
[13:16:18] <robin__> les_w, good money on marking ...
[13:16:30] <les_w> we tried it some
[13:16:37] <les_w> I have to say pretty neat
[13:16:44] <les_w> cost was $50k
[13:16:45] <DanF_DrC> what's marking?
[13:16:49] <robin__> DanF_DrC, nah, mine is 30Kw of arc lamps onto a YAG rod ... solid state as it gets in this business
[13:17:01] <Jymmm> DanF_DrC: Like the model number on router bits
[13:17:14] <DanF_DrC> ?
[13:17:20] <robin__> etching
[13:17:25] <les_w> we marked metals like aluminum, steel, and titanium
[13:17:28] <DanF_DrC> ah
[13:17:33] <robin__> ti?
[13:17:35] <robin__> kewl
[13:17:36] <les_w> was suprised the aluminum marked so well
[13:18:46] <robin__> qswitched thing I take it?
[13:18:54] <les_w> Ti is dark and marked very well
[13:18:59] <les_w> yeah q switched
[13:19:10] <robin__> the damage threshold on Ti is very high ...
[13:19:23] <les_w> to the part?
[13:19:35] <robin__> you need a lot of energy to do anything to it
[13:19:38] <DanF_DrC> who needs their things marked?
[13:19:44] <DanF_DrC> and can't do it themselves
[13:19:52] <robin__> DanF_DrC, EVERYONE
[13:19:57] <DanF_DrC> hehe wrong
[13:20:04] <DanF_DrC> try again
[13:20:10] <les_w> not sure...freind asked for help but he needs mostly marketing help
[13:20:17] <Jymmm> Colored Laser Engraving http://www.color-laser-engraver.com/what.htm
[13:20:18] <robin__> well, nearly everyone ... its a booming market
[13:20:31] <les_w> the system is very easy to use...nice cam comes with it
[13:21:16] <les_w> I'll shoot him any business I have
[13:21:31] <DanF_DrC> neat that it can make colors with light
[13:21:34] <robin__> A friend got a trumpf one ... on appro. "have it for 3 months, see if theres any work"
[13:21:42] <robin__> hes flat out on it now
[13:21:47] <les_w> really
[13:21:53] <robin__> * robin__ nods
[13:21:57] <les_w> what kind of jobs?
[13:22:30] <robin__> small parts ... aircraft bits, just "engineering components" mainly
[13:23:54] <les_w> ok
[13:24:22] <robin__> les_w, http://www.laserprocess.co.uk/markitplace.asp
[13:24:46] <les_w> woops here comes big backhoe...we are digging some stumps this morning
[13:24:51] <les_w> thanks for link
[13:25:40] <robin__> enjoy :)
[13:25:45] <robin__> post pics !
[13:25:53] <fenn> they laser engrave IC packages?
[13:25:58] <robin__> sure
[13:26:02] <les_w> of the golf course work?
[13:26:04] <les_w> haha ok
[13:26:30] <robin__> thats normal in the semi industry ... mostly done in house though
[13:28:04] <DanF_DrC> so who needs marking again? : )
[13:28:42] <fenn> DanF_DrC: go to any hardware store and look at the taps
[13:28:59] <fenn> they are all laser engraved because you cant stamp the numbers onto the tap without distorting it
[13:29:15] <DanF_DrC> would just think that if a single person could buy the marker then the factory could have one too. but maybe not
[13:29:17] <Jymmm> taps, router bits, endmills, etc
[13:29:20] <fenn> can you spot the difference between an 8mm thread and a 5/16 thread?
[13:29:30] <anonimasu> I wish they'd do that to drills.. too
[13:29:40] <anonimasu> small drills..
[13:29:44] <anonimasu> I hate it when the markings wear away
[13:29:57] <fenn> drills arent good for anything accurate
[13:30:06] <fenn> just pick one taht looks about right :)
[13:30:15] <Jymmm> anonimasu and thus drill indexes were invented =)
[13:30:33] <fenn> heh i made a suction-fit endmill holder with crappy chinese drills
[13:30:49] <anonimasu> fenn: drills are very accurate..
[13:30:54] <anonimasu> but they just dont make round holes ;)
[13:36:12] <DanF_DrC> when a motor has the ability to determine position it is a servo right?
[13:38:00] <fenn> a servo is more than just a regular DC motor with an encoder
[13:38:18] <DanF_DrC> that was actually a rhetorical educational question : )
[13:38:26] <DanF_DrC> I already knew that it was true :)
[13:38:50] <DanF_DrC> fenn, that's the common understanding of the word but not sure it's true
[13:38:54] <fenn> it is lower inertia, has finer commutator segments, more precise bearings and loewr friction brushes
[13:39:40] <anonimasu> :)
[13:40:15] <fenn> phantom was having problems converting a dc motor for use in a cnc machine
[13:40:30] <fenn> said he couldn't move the rotor less than 120 degrees
[13:40:37] <fenn> it was a DC motor too
[13:40:56] <fenn> heh time for bed for real now
[13:41:04] <anonimasu> :)
[13:41:12] <anonimasu> DanF_DrC: you should ask les about threadmill motors..
[13:41:43] <DanF_DrC> anonimasu, why?
[13:41:50] <DanF_DrC> fenn, cya
[13:42:10] <fenn> nite nite
[13:42:14] <anonimasu> DanF_DrC: if you are interested in them..
[13:42:17] <anonimasu> perhaps?
[13:42:29] <DanF_DrC> not aware of any interest in them
[13:42:45] <DanF_DrC> didn't know the term even
[13:42:53] <fenn> treadmill motor
[13:43:01] <anonimasu> err yeah..
[13:43:04] <fenn> like you get for free from an exercise equipment place
[13:43:06] <DanF_DrC> but I take it it is the principle often used in servos
[13:43:34] <DanF_DrC> ah you mean the exercise device
[13:43:36] <DanF_DrC> :)
[13:43:41] <anonimasu> you can use them with encoders.. for cnc machines
[13:43:45] <anonimasu> they are pretty good..
[13:44:16] <DanF_DrC> do they have encoders?
[13:44:30] <anonimasu> no
[13:44:38] <anonimasu> not as far as I know..
[13:44:45] <DanF_DrC> so it's an electrical motor?
[13:44:50] <anonimasu> yeah..
[13:44:58] <anonimasu> ask les when he gets back :)
[13:45:23] <anonimasu> * anonimasu has no clue but you can use them as servos nicely
[13:45:49] <DanF_DrC> thanks but I'm not a big fan of the scrapheap challenge approach
[13:46:18] <anonimasu> * anonimasu sighs
[13:46:32] <anonimasu> you can buy them new too cheaper then servos..
[13:46:35] <anonimasu> way cheaper.
[13:46:57] <DanF_DrC> that would be better but still missing the encoder
[13:48:27] <anonimasu> not my problem really you keep saying servos with encoders are too expensive.. and that you cant understand why..
[13:48:46] <anonimasu> stop making problems for yourself.. :D
[13:49:15] <DanF_DrC> I think it would be better if you stop giving me crap advice : )
[13:49:33] <anonimasu> www.galilmc.com
[13:49:34] <DanF_DrC> these doesn't look too expensive either: http://www.transmotec.com/product.asp?cat=9
[13:49:43] <anonimasu> thoose servos rock
[13:49:48] <anonimasu> ah, try to buy them in single qt..
[13:49:58] <anonimasu> transmotec sucks for that
[13:50:42] <anonimasu> yeah but thoose arent free/cheap either
[13:51:14] <anonimasu> I tried to get a quote on some solenoids from them at work.. for a prototype, they hardly wanted to discuss anything in a quantity < 20
[13:51:33] <DanF_DrC> they do have a pricelist for single piece tho
[13:52:06] <DanF_DrC> but granted it is more expensive. a practice I don't like either
[13:52:34] <anonimasu> well bbl
[14:52:47] <DanF_DrC> does anyone have the actual yahoo group name for the geckodrive grex?
[14:59:53] <rayh-away> rayh-away is now known as rayh
[15:10:15] <Jymmm> DanF_DrC: http://finance.groups.yahoo.com/group/geckodrive/
[15:11:38] <DanF_DrC> yep found it just a few seconds ago : )
[15:48:57] <K4ts> hello
[16:02:45] <Bo-Dick> could someone tell me why my stepper driver gives double pulses only when my stepper motor is connected to it?
[16:04:58] <skunkworks> probably noise getting back into the driver cicuit. does it go away when you lower the supply voltage?
[16:06:15] <Bo-Dick> yeah
[16:07:47] <Bo-Dick> it was 20 volts initially. it disappeared at 7 volts. but now the motor isn't strong enough
[16:11:43] <rayh> logger_aj, bookmark
[16:11:44] <rayh> See http://solaris.cs.utt.ro/irc/irc.freenode.net:6667/emc/2006-04-02#T16-11-43
[16:12:26] <Bo-Dick> it seems like the disturbances goes backwards from the motor through the transistor h-bridge, and to the digital logics circuits!
[16:14:54] <Bo-Dick> it it was induced disturbances from the cables and wires and so on it would behave this way even without the motor. it performs normally without a motor hooked to it.
[16:23:10] <DanF_DrC> what brand is it Bo-Dick?
[16:32:59] <giacus> uhmmm
[16:33:10] <giacus> Jymmm:
[16:33:11] <dmessier> i just fired up my old propane pick up... motor runs like a clock.. but EVERY liquid is near empty... thd the powersteering seems to have siezed
[16:34:08] <dmessier> she's gonna need some LOVE
[16:34:26] <giacus> nope
[16:34:38] <giacus> she's gonna take the iron and work ..
[16:34:46] <giacus> :D
[16:35:11] <giacus> hey guys, i'm happy to announce you I done my website !
[16:35:15] <giacus> http://www.giacus.org/
[16:35:19] <giacus> :P
[16:35:23] <giacus> incredible ..
[16:35:40] <giacus> I just learn xhtml and css in few hours
[16:35:46] <giacus> dunno how I did :(
[16:35:49] <giacus> haha
[16:36:25] <giacus> the only thing i've doubts is the layout colour
[16:36:32] <giacus> is it for girls ? O_O
[16:36:36] <giacus> haha
[16:37:19] <rayh> And the whole list hammers the giacus website. Almost as bad as a slashdot attack.
[16:37:33] <giacus> :P
[16:37:50] <giacus> hey rayh it is very light
[16:38:04] <giacus> only png images ;)
[16:38:19] <giacus> liquid layout should be ok for small devices (pda)
[16:38:25] <giacus> I've to test it
[16:38:52] <rayh> looks good.
[16:39:02] <giacus> :)
[16:39:10] <giacus> ty
[16:41:40] <giacus> xhtml transitional seems to be pretty friendly
[16:41:49] <giacus> strict was hard ..
[16:42:18] <giacus> at least for me, first time I write html code by hand
[16:43:05] <giacus> and working, I found bluefish its a nice editor
[16:45:54] <giacus> a funny thing I discovered
[16:46:26] <giacus> png transparent images background isint supported by IE
[16:46:46] <giacus> :D
[16:47:03] <giacus> stupid browser
[16:51:21] <anonimasu> hm
[17:00:21] <vegga> hello, I'm going to do a milling machine myself. I want to use emc. I don't want to buy any made hardware, is there any free hardware (motor drivers,etc) is ready for emc? I was thinking to make the milling with FPGA's and dc motors with encoders to close the loop
[17:00:51] <giacus> nice
[17:01:10] <vegga> i'm a little lost cause i'm beginning
[17:01:20] <giacus> are you able to hack drivers and write low level code ?
[17:01:29] <vegga> yes
[17:01:32] <vegga> i think so
[17:01:51] <giacus> well, emc is open as you know
[17:02:00] <vegga> yep
[17:02:07] <giacus> many peoples use homeade drivers
[17:02:25] <giacus> not homemade motors.. for what I know
[17:02:29] <vegga> i want something to begin with, i'm speaking about the motor drivers
[17:02:30] <giacus> :)
[17:02:43] <vegga> no, homemade motors no..:D
[17:02:43] <giacus> servo drivers ?
[17:02:46] <vegga> yes
[17:02:50] <vegga> with pwm
[17:02:57] <vegga> and encoder
[17:03:01] <giacus> there's a pseudo-pwm in emc2
[17:03:04] <vegga> like the printers
[17:03:11] <giacus> and encoder, pid, etc
[17:03:27] <giacus> you can find complete documentation on the wiki
[17:03:38] <vegga> ahaps, and is there any free hardware ?
[17:04:01] <vegga> schematics or vhdl or something
[17:04:11] <vegga> I don't want to buy the gecko drivers
[17:04:24] <giacus> I bought it ..
[17:04:34] <giacus> months ago
[17:04:43] <vegga> it's too much money for me, 3 drivers
[17:04:45] <vegga> jeje
[17:04:47] <giacus> you can try to build your own drivers
[17:04:57] <vegga> yes, that's the thing
[17:05:08] <giacus> but remember require a lot of time, and maybe the result will be poor
[17:05:19] <giacus> lot of math ..
[17:05:25] <giacus> to learn
[17:05:38] <giacus> I suggest you to start reading the wiki
[17:05:53] <vegga> yes, so i see there are no free drivers in the web that are compatible with emc
[17:05:56] <vegga> ok
[17:06:05] <vegga> thankyou giacus
[17:06:09] <giacus> depend on what you want to drive
[17:06:18] <giacus> np
[17:06:58] <vegga> you have built it with the gecko drivers?
[17:07:01] <jepler> vegga: Here's a free design that you can hook to your PC with a parallel port. It's for stepper drivers: http://pminmo.com/l297-8/l297-8.htm
[17:07:26] <jepler> vegga: It's not based on FPGA however
[17:07:39] <vegga> thanks a lot jeplet, it's a pitty that they are not servos jeje
[17:07:49] <Imperator_> vegga: do you know the mesa FPGA PCI card
[17:08:03] <giacus> vegga: I should build my next machine and use geckos servodrive
[17:08:05] <vegga> Imperator_: yes, i was reading now the specs
[17:08:29] <vegga> Imperator_: this is the thing I like
[17:08:53] <Imperator_> we have made here some own extension boards
[17:09:06] <Imperator_> breakout boards
[17:09:10] <vegga> anyone uses the mesa card for the machine?
[17:09:41] <Imperator_> I don't know but some have bought the card
[17:09:45] <vegga> Imperator_: ahaps, this is my will, doing my own fpga board like the mesa one
[17:10:12] <Imperator_> dont build it by yourself
[17:10:12] <anonimasu> vegga: why building your own?
[17:10:29] <Imperator_> it is so cheap, that makes no sense
[17:10:31] <vegga> Imperator_: i thought that is possible to do a microblaze processor in the fpga whith linux, so the pc is not needed
[17:10:48] <Imperator_> uff
[17:11:04] <anonimasu> ^_^
[17:11:28] <anonimasu> http://www.imec.be/rtlinux/
[17:11:32] <anonimasu> that's a better bet..
[17:11:43] <Imperator_> take a industrial pc or much cheaper a via epia board
[17:11:59] <vegga> anonimasu: ahaps
[17:12:09] <jepler> Imperator_: have any first-hand experience with how emc performs on those via boards?
[17:12:27] <Imperator_> nope
[17:12:51] <anonimasu> vegga: what?
[17:13:06] <dmessier> how many axes can i hit simultaniosly with emc2
[17:13:07] <Imperator_> but someone here has a epia board, maybe rayh knows hwo
[17:13:11] <Imperator_> who
[17:13:22] <Imperator_> six
[17:13:32] <dmessier> thx... should work
[17:13:41] <giacus> I also have epia
[17:14:11] <dmessier> im thinkin of a paraglider simulater thats .. interactive
[17:14:21] <anonimasu> what kind of ports does the epia boards have?
[17:14:36] <anonimasu> ah nm found the spec
[17:14:40] <rayh> HAL allows for 8 but EMC only handles 6 right now.
[17:15:04] <dmessier> thx ray.. so a plc axis is possible??
[17:15:08] <anonimasu> no com port..
[17:15:15] <rayh> The comparable mesa card has software for 12.
[17:15:21] <rayh> Sure.
[17:15:42] <Imperator_> epia boards have com ports
[17:15:47] <rayh> In fact you could build a plc axis in HAL without using any emc interface.
[17:16:26] <rayh> Like a pick and place or any set of looping motions.
[17:16:35] <vegga> rayh; i see the mesa card is very interesting, and how does it connect to the pc, via pci? i see it's a pc104+
[17:16:58] <Imperator_> look at the m20i
[17:17:15] <rayh> The one that we have software for is the m5i20 and it's pci.
[17:17:22] <dmessier> 1 pitch - 2 for roll - 2 for yah - 2 for brakes and 2 for speed bar
[17:17:24] <Imperator_> 5i20 sorry
[17:17:51] <rayh> I sent a pc104 card to Paul but I've not seen any software for it.
[17:18:15] <anonimasu> Imperator_: how does the mesa behave?
[17:18:34] <rayh> Okay from what I've herd.
[17:18:35] <Imperator_> how do you mean that ?
[17:18:48] <anonimasu> behave/work?
[17:18:50] <rayh> heard. sorry.
[17:19:05] <rayh> I've got one here but must set it up with motors before I'll know from personal experience.
[17:19:05] <vegga> i like the 4i34m
[17:19:15] <anonimasu> ah ok
[17:20:03] <rayh> The owner of Mesa has just started putting files in the repository.
[17:20:18] <skunkworks> website/
[17:20:20] <skunkworks> ?
[17:20:41] <skunkworks> (mesa)
[17:20:49] <vegga> www.mesanet.com
[17:21:01] <skunkworks> thank you
[17:21:28] <vegga> it would be beautiful having these in opencores.org
[17:21:49] <anonimasu> 7I30 Quad 100 Watt H-bridges for 4I27,4I34,4I65,5I20,7I60
[17:21:50] <anonimasu> yikes
[17:21:58] <Imperator_> anonimasu: i made my own breakout boards, the counter card works fine, for the DAC board i have to chanche a lot in the fpga software that is not done right now. the card itself is very good
[17:22:13] <anonimasu> you could really create a neat motor driver on the fpga..
[17:22:42] <anonimasu> or well thoose 0-10v output boards..
[17:22:47] <anonimasu> and real servoamps..
[17:23:29] <anonimasu> err power sSoftDMC Digital Motion Control firmware for FPGA based I/O cards
[17:23:30] <anonimasu> err
[17:23:31] <anonimasu> SoftDMC Digital Motion Control firmware for FPGA based I/O cards
[17:23:32] <Imperator_> that has done mesanet already with that breakoutboard you can buy
[17:24:07] <anonimasu> what?
[17:24:51] <anonimasu> well brb..
[17:25:36] <Imperator_> thats it
[17:26:04] <Imperator_> but i like a real servo amp more thats why i made a board with a real DAC
[17:53:15] <Bo-Dick> could someone tell me what causes disturbances from the motor coil back to the TTL circuits in my stepper driver design? http://www.carmi.se/misterstarshine/img/block.gif
[17:54:21] <alex_joni> did you put caps on all the circuits?
[17:54:22] <jmkasunich> Bo-Dick: where are you bypass caps?
[17:54:42] <jepler> and protection diodes?
[17:54:45] <Bo-Dick> uuuhm. "bypass caps"?
[17:55:05] <jmkasunich> you need to read more electronics books
[17:55:18] <jmkasunich> every circuit makes electrical noise
[17:55:21] <alex_joni> jmkasunich: at 20V this isn't THAT bad :)
[17:55:24] <Bo-Dick> u mean those near the voltage regs?
[17:55:28] <jmkasunich> motor circiuts make tons of noise
[17:55:37] <jmkasunich> caps are used to filter it out
[17:56:02] <Bo-Dick> where would you put the caps if you where in my situation?
[17:56:25] <jmkasunich> you should have 1-10uf at the input and output of each voltage regulator, 0.1uF at each chip, and several hundred uF at the H bridge (in parallel with some high-freq caps like 0.1uF)
[17:58:16] <jmkasunich> also, why the regulator and current limiter on the motor supply?
[17:58:39] <Bo-Dick> the current limiter limits the current to the motors coils
[17:59:07] <Bo-Dick> you mean the LM317 is redundant?
[17:59:13] <jmkasunich> a resistor would do that too
[17:59:34] <alex_joni> Bo-Dick: what voltage are the motors referenced?
[17:59:35] <Bo-Dick> an active current limiter is more responsive and powerful
[17:59:49] <jmkasunich> thats true
[17:59:53] <Bo-Dick> i'm gonna have a maximum voltage of 30 voolts
[18:00:06] <jmkasunich> most drives use PWM to the transistors to control current, I didn't realize you weren't doing that
[18:00:10] <Bo-Dick> right now i'm testin' the device with only 20 volts
[18:00:11] <jmkasunich> so yes, you need a limiter
[18:00:24] <jmkasunich> but you don't need the LM317
[18:00:28] <Bo-Dick> i've got a linear current limiter
[18:00:39] <alex_joni> jmkasunich: yes, the current limiter, but running at 23V instead of 20V should be fine too
[18:00:41] <jmkasunich> this circuit is increddibly inefficient
[18:00:48] <alex_joni> so I wouldn't put the LM317
[18:00:58] <jmkasunich> right
[18:01:01] <Bo-Dick> i'm gonna remove the LM317
[18:01:20] <jmkasunich> Bo-Dick: what is the motor volts and amps rating?
[18:01:28] <alex_joni> you only need to worry about the voltage if it's ~ 10 times more than the motor rating
[18:01:39] <jmkasunich> alex: not true, that is for PWM drives
[18:01:41] <Bo-Dick> i'm gonna run the motors at around 200mA
[18:01:51] <alex_joni> jmkasunich: oh, right.. this is not PWM
[18:01:54] <jmkasunich> tiny tiny motors?
[18:02:24] <jmkasunich> wow, are those really 2n2222 and 2n2907 transistors?
[18:02:46] <alex_joni> jmkasunich: this is tiny: http://www.livescience.com/technology/050915_smallest_robot.html
[18:02:57] <Bo-Dick> no, ignore the transistor names
[18:03:05] <Bo-Dick> they are TIP31C and TIP32C
[18:03:16] <Bo-Dick> updated! http://www.carmi.se/misterstarshine/img/block.gif
[18:03:49] <jmkasunich> and caps at the H bridge
[18:03:55] <jmkasunich> from top to bottom
[18:04:20] <Bo-Dick> i don't know how to connect the caps at the bridge
[18:04:36] <jmkasunich> from top to bottom
[18:04:55] <alex_joni> Bo-Dick: on the power supply to the bridge
[18:04:56] <jmkasunich> top of upper diode to bottom of lower diode = supply to ground
[18:05:54] <alex_joni> hmm.. is the driving of those transistors ok?
[18:06:26] <jmkasunich> not for any real power level
[18:06:33] <jmkasunich> but this is so tiny it might be ok
[18:06:52] <jmkasunich> 200mA / transistor beta of maybe 50 = 4mA required
[18:07:02] <alex_joni> I would be concearned about shorting the PSU by mistake
[18:07:05] <jmkasunich> 4mA * 2.7K = 10V
[18:07:13] <jmkasunich> I take that back, the driver isn't ok
[18:07:32] <Bo-Dick> the psu can't be shorted!
[18:07:34] <jmkasunich> alex: that common emitter connection can't get a shoot-thru fault
[18:08:39] <jmkasunich> Bo-Dick: are the TIP31 and 32 darlingtons, or regular transistors?
[18:09:26] <Bo-Dick> they're in a darlington config. it isn't shown in the image
[18:09:55] <jmkasunich> what is the minimum current gain (beta, or hfe on the data sheet)?
[18:10:16] <Bo-Dick> i think it's aroung 100 somewhere
[18:10:32] <jmkasunich> ok, so for 200mA load current you need 2mA base current
[18:10:55] <jmkasunich> on the side of the bridge that is high, the base current is supplied thru the 2.7K resistor
[18:10:55] <Bo-Dick> yeah
[18:11:12] <jmkasunich> so you have 2mA * 2.7K = 5.4 volts drop across the resistor
[18:11:21] <jmkasunich> another 1.2V drop across the darlington
[18:11:36] <jmkasunich> so the output can never get closer than 6.6V below the supply
[18:11:55] <Bo-Dick> thats true
[18:12:18] <jmkasunich> and that 6.6V * 200mA is dissipated in the top transistor
[18:12:26] <jmkasunich> 1.32 watts
[18:12:41] <Bo-Dick> i've got heat sinks
[18:12:44] <Jymmm> top? or first?
[18:13:01] <jmkasunich> since you are running such tiny currents, it might be OK, but there is no way this circuit can be scaled up for bigger motors
[18:13:08] <jmkasunich> its horribly inefficient
[18:13:42] <Bo-Dick> i'm aware of that
[18:14:47] <Bo-Dick> but the real problem now is that the TTL circuits get so much disturbance they flippin around out of control
[18:15:03] <Bo-Dick> this only happens when the motor is hooked to the driver
[18:15:20] <Bo-Dick> otherwise the signal looks fine on the oscilloscope
[18:15:32] <jmkasunich> what is the physical layout of the circuit like?
[18:15:48] <jmkasunich> (schematics don't show stray inductance and capacitance, etc)
[18:16:24] <Bo-Dick> the ttl are on a separate board
[18:16:50] <Bo-Dick> the h-bridges on a separate board
[18:16:55] <jmkasunich> that board has step and dir inputs, two outputs, +5 and ground, right?
[18:17:05] <jmkasunich> (the ttl board)
[18:17:18] <jmkasunich> and the h bridge board has +20, ground, and two inputs
[18:17:18] <Bo-Dick> yes
[18:17:31] <jmkasunich> where is the 7805?
[18:17:37] <jmkasunich> on the ttl board?
[18:18:14] <Bo-Dick> no it's at the supply
[18:18:28] <jmkasunich> on another board?
[18:18:29] <Bo-Dick> right now i've hooked the supply and current limiter on a breadboard
[18:18:46] <jmkasunich> can you post a pic?
[18:18:57] <Bo-Dick> the ttl board looks like this: http://www.carmi.se/misterstarshine/Projects/logic.jpg
[18:18:59] <jmkasunich> this is almost impossible to do in words
[18:19:26] <jmkasunich> no caps anywhere
[18:19:28] <Bo-Dick> http://www.carmi.se/misterstarshine/Projects/logic_rear.jpg
[18:19:31] <giacus> giacus is now known as giacus_afk
[18:20:02] <Bo-Dick> i could always wrap the ttl board in a ground-foil
[18:20:21] <jmkasunich> you should have a 0.1uF or 0.01uF cap from Vcc to Gnd at _every_ TTL chip
[18:20:40] <jmkasunich> that is the first rule of digital electronics
[18:21:13] <jmkasunich> install chips, install caps, then start wiring
[18:21:31] <Bo-Dick> can they break without this protection?
[18:21:44] <jmkasunich> break as in be destroyed, maybe
[18:21:50] <jmkasunich> break as in not work right, definitely
[18:22:07] <Bo-Dick> in fact two of the ic's you see broke without an apparent reason
[18:23:18] <Bo-Dick> so far i've learnt that i should do three things to fix these problems. 1) caps on the voltage regulator 2) caps on every TTL ic 3) caps at the h-bridges. is that all to it?
[18:23:30] <jmkasunich> thats a start
[18:23:47] <jmkasunich> power electronics can be very tricky
[18:24:03] <jmkasunich> stray inductance and stray capacitance can really mess things up
[18:24:13] <Bo-Dick> i never fully understood how the caps should be applied to the h-bridges
[18:24:17] <jmkasunich> fortunately you are running at such low power you can get away with a lot
[18:24:35] <jmkasunich> from the top of the bridge to the bottom
[18:25:00] <Bo-Dick> just across the whole bridge?
[18:25:16] <Bo-Dick> physically near the bridge then?
[18:25:23] <jmkasunich> yea
[18:25:25] <jmkasunich> yes
[18:25:30] <Bo-Dick> all h-bridges are in parallel
[18:25:43] <Bo-Dick> i need one cap for each bridge then?
[18:25:52] <alex_joni> Bo-Dick: 2 caps / bridge
[18:25:54] <jmkasunich> that depends on the layout
[18:25:59] <alex_joni> one small, one large ;)
[18:26:01] <jmkasunich> got a pic of the bridge?
[18:26:25] <Bo-Dick> http://www.carmi.se/misterstarshine/Projects/darlingbridge.gif
[18:26:48] <Bo-Dick> the diodes are missing in the image!
[18:27:00] <jmkasunich> you need a high frequency cap (0.1uF maybe) at each half-bridge (8 total if you have 4 H-bridges)
[18:27:11] <jmkasunich> I meant a photo, showing how they are layed out
[18:27:32] <jmkasunich> if they are close to gether, you could probably have one 100uF cap for all four, as long as you have the small caps at each one
[18:28:24] <Bo-Dick> http://www.carmi.se/misterstarshine/Projects/drive.jpg
[18:28:54] <Bo-Dick> http://www.carmi.se/misterstarshine/Projects/under.jpg
[18:29:12] <Bo-Dick> http://www.carmi.se/misterstarshine/Projects/closeup.jpg
[18:29:52] <jmkasunich> what are the round transistors?
[18:30:19] <jmkasunich> (the TIP31 and 32 are the TO-220 ones, right?
[18:30:29] <Bo-Dick> yepp
[18:30:35] <jmkasunich> and the diodes have blue tubing around their leads
[18:31:06] <Bo-Dick> round-transistors: N12101
[18:31:12] <Bo-Dick> yepp
[18:31:16] <jmkasunich> what are they for?
[18:31:31] <Bo-Dick> the blue tubings are for isolation
[18:31:40] <jmkasunich> I know
[18:31:43] <jmkasunich> what are the N12101
[18:31:46] <jmkasunich> for?
[18:32:00] <Bo-Dick> they are transistors
[18:32:13] <Bo-Dick> they are the first step in the darlingtons
[18:32:14] <jmkasunich> but what are they for?????!?!?!?!?
[18:32:33] <jmkasunich> I thought you said the TIP31 was a darlington?
[18:32:48] <alex_joni> they are arranged in darlington layout he said
[18:32:52] <jmkasunich> now you say you made the darlington yourself with two transistors
[18:33:00] <Bo-Dick> yepp
[18:33:36] <Bo-Dick> in the block diagram i substituted the darlington pair in one symbol. sorry for the confusion
[18:34:36] <jmkasunich> ok
[18:34:52] <Bo-Dick> but apparently caps can be added to the design in order to reduce noise.
[18:35:10] <jmkasunich> yes
[18:35:48] <jmkasunich> I would add one 0.1uF from the collector of Q31 to the collector of Q40
[18:36:02] <Bo-Dick> ok
[18:36:04] <jmkasunich> another from the collector of Q36 to the collector fo Q39
[18:36:39] <jmkasunich> same for each bridge, total of 8
[18:36:41] <Bo-Dick> in fact the 7406's are on a separate board as well. http://www.carmi.se/misterstarshine/Projects/buffer.jpg
[18:36:57] <jmkasunich> and one 100uF across the power supply terminals of the bridge board
[18:40:16] <Bo-Dick> i've got a lot of soldering to do now.
[18:40:57] <jmkasunich> any particular reason for the 3W 2.7K resistors?
[18:41:33] <Bo-Dick> to stand the voltage
[18:41:45] <jmkasunich> 20V / 2.7K = 7.4mA * 20V = 0.148W you could have used 1/4W
[18:42:00] <jmkasunich> or 1/2 watt to be very conservative
[18:42:31] <Bo-Dick> i was initially thought to be designed for a higher voltage. but from this standpoint they do nothing but take up a lot of space.
[18:42:41] <jmkasunich> the 7406
[18:42:43] <jmkasunich> oops
[18:43:05] <jmkasunich> the 7406s are only good for 30 or 40 volts max aren't they?
[18:43:15] <Bo-Dick> unfortunately yes
[18:43:20] <jmkasunich> if they are rated for 40, you shouldn't run the supply over 30
[18:43:35] <Bo-Dick> they're rated for 30
[18:43:40] <jmkasunich> actually, without caps, I bet you get more than 40V spikes when you switch the transistors
[18:44:07] <Bo-Dick> well one 7406 got broke
[18:45:45] <jmkasunich> thats probably why
[18:46:03] <Bo-Dick> do you think the caps will sort this out?
[18:46:55] <jmkasunich> without caps on the bridges there is no way it can work
[18:47:06] <jmkasunich> with caps on the bridges, probably (but other things could still be wrong)
[18:48:18] <Bo-Dick> would the caps on the bridges affect the responsiveness of the stepper driver?
[18:48:36] <jmkasunich> the caps on the bridges will keep it from blowing itself up
[18:49:40] <Jymmm> "Capt, she's gonna blow!"
[18:50:46] <jmkasunich> well at such power, "blow" is a bit of an exageration
[18:51:02] <jmkasunich> the ones I work on do blow, and very loud
[18:51:03] <Bo-Dick> the bridge-board has eight h-bridges. that will need 16 0.1uF caps on the collectors. will it be sufficient to add one 100uF at the supply rails on that board?
[18:51:16] <Jymmm> jmkasunich: Blow as in poof! Not as in knock out the north wall =)
[18:51:41] <jmkasunich> Bo-Dick: I can'
[18:51:46] <jmkasunich> I can't say for sure
[18:52:11] <Bo-Dick> it's worth trying out anyway.
[18:52:20] <jmkasunich> remember, I'm used to working with much larger and faster switching stuff
[18:52:33] <Bo-Dick> i wanna thank you for all help. you've been incredibly helpful.
[18:52:34] <jmkasunich> so I might be recommending something that is overkill for you
[18:52:42] <jmkasunich> but you definitely need the 100uF
[18:53:16] <jmkasunich> your darlingtons switch slower than mosfets, so maybe you don't need the 0.1uF (or need as many)
[18:53:45] <Bo-Dick> i'm gonna add them anyway i think
[18:55:35] <Bo-Dick> thanks for all help particularly you jmkasunich!
[18:55:43] <jmkasunich> you're welcome
[18:56:50] <alex_joni> jmkasunich: wondering what he wants to do.. I mean why not just build a L297/298 driver
[18:57:08] <jmkasunich> dunno
[18:57:32] <jmkasunich> the construction technique says he has a very low budget, or very limited sources of parts
[18:57:38] <jmkasunich> (I wonder where he is?)
[18:57:51] <alex_joni> .se
[18:57:57] <alex_joni> at least the webpage is
[18:58:49] <Jymmm> Stockholms
[19:04:59] <anonimasu> who is?
[19:05:02] <skunkworks> low budget. (he also thought steppers where a lot simpler than he knows now)
[19:05:12] <anonimasu> ah that one
[19:05:35] <anonimasu> ah bo dick?
[19:05:48] <skunkworks> :)
[19:06:21] <anonimasu> ^_^
[19:06:49] <anonimasu> he's spent more time then he would have needed collecting tin cans to afford a gecko
[19:08:18] <skunkworks> I have to admit - I started pretty much his route. about 10 years ago. descrete componants -> got the theory down pretty good. went to a integrated stepping chip which was pwm - then decided that I needed microstepping. now we get cheap compumotor stepping drives from ebay among others.
[19:08:29] <jmkasunich> for the power level hes working at he could use a xylotex at about 1/3 the cost of a gecko
[19:09:03] <anonimasu> it's not as cool though, but the easy way is usually good if you want to make parts reasonably quick
[19:09:03] <Jymmm> sounds like he sorta wants to learn too
[19:09:13] <jmkasunich> I like to do discrete design too
[19:09:26] <jmkasunich> but he needs to read more before he starts building
[19:09:45] <jmkasunich> and he should only build one axis and get that working before duplicating it 4 or 8 times
[19:09:51] <anonimasu> Jymmm: yeah like "where can I get schematics for geckos the parts must be like $8"
[19:09:56] <anonimasu> ;)
[19:10:01] <skunkworks> kinda sounds like he built the first circuit he found
[19:10:04] <Jymmm> anonimasu: Is that what he said?
[19:10:04] <anonimasu> yeah..
[19:10:09] <Jymmm> lol
[19:10:11] <anonimasu> Jymmm: werent you here before?
[19:10:21] <Jymmm> in and out
[19:10:32] <anonimasu> yeah.. that was what was said.. in the very beginning
[19:10:38] <Jymmm> lol
[19:11:08] <anonimasu> basically stepper drivers are so easy I dont get how they can be so expensive..
[19:11:15] <anonimasu> :)
[19:11:18] <jmkasunich> heh
[19:11:52] <anonimasu> I am kind of curious about designing a stepper driver though.. for the fun of it..
[19:12:20] <anonimasu> I suck at electronics
[19:12:21] <anonimasu> :)
[19:12:22] <Jymmm> anonimasu design a controller
[19:12:28] <anonimasu> controller?
[19:12:37] <skunkworks> I have a degree and suck at it ;)
[19:12:44] <Jymmm> like the thing Jon sells, but w/o driver dependancy
[19:12:49] <anonimasu> I'd love to get into fpga's..
[19:13:03] <skunkworks> what the heck does fpga stand for?
[19:13:05] <anonimasu> pulse generator
[19:13:09] <jepler> field-programmable gate array
[19:13:11] <anonimasu> field programable gate array
[19:13:14] <skunkworks> thanks
[19:13:20] <jmkasunich> what happens when I screw up my design: http://home.att.net/~jmkasunich/Pics/CapBang1.jpg
[19:13:28] <jepler> http://www.google.com/search?q=define%3Afpga
[19:13:35] <jmkasunich> and http://home.att.net/~jmkasunich/Pics/BlownIGBT.JPG
[19:13:40] <Jymmm> jmkasunich where you in the room at the time?
[19:13:45] <anonimasu> jmkasunich: you rock!
[19:13:47] <anonimasu> ^_^
[19:13:50] <skunkworks> was that a electrolitic?
[19:13:52] <jepler> jmkasunich: nice -- how tall is that cap?
[19:13:54] <jmkasunich> yes
[19:14:03] <jmkasunich> 8" tall, 3" dia
[19:14:08] <Jymmm> jmkasunich OUCH! Those suckers are LOUD when they pop
[19:14:09] <skunkworks> bet that made a little noise
[19:14:12] <anonimasu> that's why you rock ^_^
[19:14:25] <anonimasu> I remeber that your company built vfds..
[19:15:21] <Jymmm> anonimasu: Build a 500KHz PCI parallel port =)
[19:15:29] <anonimasu> Jymmm: what?
[19:15:50] <Jymmm> anonimasu: Do you know what a PCI slot is?
[19:15:55] <anonimasu> yeah
[19:16:00] <Jymmm> anonimasu: Do you know what a paralle port is?
[19:16:28] <anonimasu> and I know pci is hell-ish to design boards for
[19:17:12] <Jymmm> anonimasu like that board you bought
[19:17:17] <anonimasu> yeah I know..
[19:17:34] <jmkasunich> me (in the middle) working on a drive in the field
[19:17:36] <jmkasunich> http://home.att.net/~jmkasunich/Pics/LF_MCC.JPG
[19:17:40] <Jymmm> but no driver dependacies... pure HW solution
[19:17:44] <jmkasunich> nothing like changing the firmware on the fly.....
[19:18:00] <anonimasu> hehe
[19:18:12] <Jymmm> whos the guy in the middle? Reminds me of Chong
[19:18:14] <anonimasu> Jymmm: isnt the usc protocol documented nicely
[19:18:24] <anonimasu> ;)
[19:18:50] <anonimasu> I think I'm gonna learn a thing or two about fpga's.. they are a nice technology
[19:19:07] <anonimasu> someday ;)
[19:19:49] <Jymmm> anonimasu: I REALLY hate driver dependancies... got bit on the ass about 10 years ago BIG TIME
[19:20:53] <Jymmm> How do faunic do it?
[19:20:58] <Jymmm> (sp)
[19:21:23] <anonimasu> the motion?
[19:21:24] <Jymmm> fanuc
[19:21:46] <Jymmm> yeah... dedicated IO ?
[19:21:50] <anonimasu> dont they run the motion control/interpolation on separate controllers?
[19:22:06] <Jymmm> like a mesa card of srots?
[19:22:09] <Jymmm> sorts
[19:22:11] <anonimasu> yeah
[19:22:24] <Jymmm> which does what over paraport?
[19:22:30] <anonimasu> nothing?
[19:22:40] <Jymmm> has to do SOMETHING =)
[19:22:55] <anonimasu> might even be like a pci card..
[19:23:02] <anonimasu> like the galilmc pci cards..
[19:23:31] <anonimasu> brb, having something to eat
[19:23:34] <Jymmm> k
[19:46:41] <Jymmm> Heh... SWP either gave me the wrong flight number, or he's gonna be landing 400 miles of where he think he is :o
[19:48:41] <anonimasu> ^_^
[19:53:42] <Jymmm> heh, we'll find out in about 20 mminutes =)
[19:58:28] <anonimasu> is he comming to you=
[19:58:28] <anonimasu> ?
[19:58:55] <Jymmm> yeah, has a electronics conf here this week
[19:59:16] <anonimasu> ah ok
[19:59:19] <anonimasu> nice
[19:59:40] <rayh> Jymmm, SanFrancisco?
[19:59:46] <Jymmm> San Jose
[20:00:16] <rayh> Okay. I grew up in Modesto, went to school in Watsonville and in the Napa valley.
[20:00:32] <rayh> More'n you wanted to know.
[20:00:50] <Jymmm> Central Valley - ouch!
[20:02:18] <rayh> That was long ago.
[20:02:54] <Jymmm> I bet =)
[20:17:26] <dave-e> well at least he had sense enough to leave.. ;-)
[20:19:26] <dave-e> I wilt with the heat and the humidity
[20:20:18] <K4ts> hello
[20:20:31] <dave-e> rayh... I have reservations for plane and car.. for Galesburg
[20:20:53] <rayh> Great. Looking forward to seeing you there again.
[20:21:09] <dave-e> Hopefully the weather will be more bearable
[20:21:40] <dave-e> and the projects not quite so intense
[20:22:30] <dave-e> I'm looking for a way to sequence jobs on emc... any ideas?
[20:23:17] <dave-e> ray must be thinking
[20:24:27] <rayh> phone brb
[20:28:11] <alex_joni> dave-e: what do you mean by sequence?
[20:28:15] <alex_joni> hi, btw ;)
[20:28:43] <dave-e> hi alex
[20:29:12] <dave-e> I would like to run several jobs one right after the other....
[20:29:24] <dave-e> automagically loading into emc and starting
[20:29:26] <cradek> dave-e: concatenate the files?
[20:30:07] <dave-e> I have reasons for keeping the separate...makes restarting easier
[20:30:47] <dave-e> otherwise cat on the files makes good sense
[20:31:32] <K4ts> hi rayh
[20:32:26] <dave-e> ray is apparently still plugged into the phone
[20:32:39] <rayh> Hi K4ts. Saw your pic on giacus's site.
[20:33:04] <dave-e> opps! he back
[20:33:12] <K4ts> :-)
[20:33:16] <dave-e> he's
[20:33:48] <alex_joni> dave-e: there are some solutions.. but all of them require some coding I'm afraid
[20:34:24] <dave-e> well this needs to be something that several people need before any time gets spend on it
[20:34:45] <alex_joni> dave-e: maybe the work on halui will permit this
[20:34:54] <alex_joni> I'll keep it in mind
[20:35:02] <dave-e> I'm not much of a coder but an outline of the approach would be interesting
[20:35:11] <alex_joni> do you know about halui?
[20:35:20] <dave-e> no
[20:35:49] <alex_joni> halui is a HAL User Interface which will allow you to build a hardware User Interface using knobs & switches & leds
[20:36:05] <dave-e> Hmmmmm
[20:36:17] <dave-e> lots of potential there
[20:36:29] <alex_joni> yeah, but also far away
[20:36:32] <alex_joni> ;-)
[20:36:54] <skunkworks> does ubuntu automatially come up in 640X480 if it doesn't get shut down properly or is it my computer?
[20:37:12] <cradek> I've not seen that behavior
[20:37:28] <dave-e> it's been pretty stable for me
[20:37:31] <skunkworks> could be my kvm switch also I suppose.
[20:37:41] <dave-e> and I can break almost anything...ask ray
[20:37:43] <skunkworks> we lost power here this weekend
[20:37:46] <cradek> could be - it might not be able to read DDC from your monitor
[20:37:56] <skunkworks> right
[20:38:06] <dave-e> gotta run....
[20:38:08] <dave-e> later
[20:38:12] <skunkworks> I didn't have the computer selected when I booted it
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[21:29:01] <skunkworks> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl/emcinfo.pl?Sample_HAL_And_ClassicLadder
[21:29:11] <skunkworks> where are these pictures now?
[21:30:31] <giacus> hello skunkworks
[21:30:39] <giacus> * giacus don't know ..
[21:30:45] <skunkworks> Hi jackey. How is it going?
[21:30:49] <alex_joni> skunkworks: give me a few minutes.. ok?
[21:30:55] <skunkworks> no problem
[21:31:04] <giacus> I'm going to remove pictures from my new website ..
[21:31:21] <giacus> K4ts: seen my photo and sayd is too dark ..
[21:31:34] <skunkworks> The one on the main page?
[21:31:34] <giacus> I was thinking to dark is better
[21:31:37] <giacus> haha
[21:31:42] <skunkworks> Yes it is a little dark ;)
[21:31:45] <giacus> don't show the bad face :)
[21:31:59] <giacus> well.. removing it
[21:32:06] <giacus> too much pictures around :P
[21:32:41] <giacus> I think the reason is another ..
[21:32:49] <giacus> K4ts: is jealous
[21:32:52] <giacus> sshhh
[21:33:03] <K4ts> no
[21:33:09] <giacus> no ?
[21:33:28] <K4ts> jeaulous?
[21:33:43] <giacus> yes, gelosa
[21:33:47] <K4ts> jealous?
[21:33:54] <K4ts> no
[21:34:27] <giacus> ok, so can I put pamela andersond in a banner in the right side of the website ? :P
[21:34:42] <giacus> just to balance ..
[21:34:45] <giacus> the things
[21:35:12] <giacus> K4ts: I'm kidding !
[21:35:18] <giacus> turn off the damn tv
[21:35:21] <giacus> :)
[21:35:25] <K4ts> mi mandi tutte le mie foto
[21:35:31] <K4ts> devo fare un mio album
[21:35:54] <giacus> what ?
[21:36:29] <giacus> should I send you all my photos ?
[21:36:36] <K4ts> yes
[21:36:51] <giacus> but you can find all in the website/gallery !
[21:37:09] <giacus> but plese .. read the terms before
[21:37:21] <giacus> as well they are gpl !
[21:37:25] <giacus> you know ?
[21:37:51] <giacus> send me an email request
[21:38:01] <giacus> I will see what I can do for you ok ?
[21:38:34] <K4ts> non sono tutte
[21:39:04] <giacus> giacus is now known as giacus_xhtml
[21:39:09] <giacus_xhtml> sorry .. :(
[21:39:28] <giacus_xhtml> just wait some day
[21:39:46] <giacus_xhtml> you can start with albums already are online
[21:40:31] <giacus_xhtml> K4ts: what are U using to build the albums ?
[21:40:36] <alex_joni> skunkworks: sorry, don't have those
[21:40:43] <alex_joni> I mailed steve to get them
[21:41:07] <K4ts> photoshowexpress
[21:41:57] <skunkworks> thats ok. Thanks
[21:42:18] <skunkworks> Just playing around with demo_step_cl
[21:42:51] <giacus_xhtml> giacus_xhtml is now known as giacus
[21:42:52] <skunkworks> have not had ladder logic sense college
[21:43:05] <alex_joni> skunkworks: I didn't know anyone linked images from the wiki to the old linuxcnc.org website :(
[21:44:04] <skunkworks> oops. I noticed where it was pointing to. :)
[21:47:08] <alex_joni> skunkworks: sorry :(
[21:48:05] <skunkworks> np.
[21:48:28] <skunkworks> just searching my ie cache just to be sure I don't have them. Doubt it though
[21:50:44] <skunkworks> not here - I will double check at home.
[21:58:15] <skunkworks> Clasic ladder is pretty neat.
[22:06:55] <alex_joni> yeah, and easy to use
[22:06:59] <alex_joni> I mean the ladder
[22:08:15] <alex_joni> ok, guys I'm off to bed
[22:08:19] <alex_joni> good night everyone
[22:08:30] <skunkworks> night ales
[22:08:32] <skunkworks> alex
[22:11:16] <giacus> G night alex_joni
[22:23:00] <giacus> K4ts: ?
[22:23:04] <giacus> sleeping ?
[22:23:18] <K4ts> no
[22:23:24] <K4ts> gimp
[22:23:38] <giacus> nice :P
[22:24:08] <giacus> K4ts: what should I put in <meta name="keywords" content= "" ?
[22:24:37] <K4ts> eh?+
[22:24:43] <giacus> porn, mp3, divx, crack, warez ?
[22:24:49] <giacus> :P
[22:25:04] <K4ts> porn?
[22:25:10] <giacus> nahh.. kidding
[22:25:17] <K4ts> pop corn
[22:25:22] <giacus> cnc, robot, robots,
[22:25:28] <giacus> :D
[22:25:38] <K4ts> mp3
[22:25:43] <giacus> ogg
[22:27:47] <giacus> 00:26 <K4ts> ah
[22:27:48] <giacus> 00:27 <K4ts> ma io nemmeno
[22:27:48] <giacus> 00:27 <K4ts> ho sto ddc
[22:27:51] <giacus> hehe
[22:28:02] <giacus> K4ts: sayd she dont have dcc
[22:28:10] <giacus> who taked it ? O_O
[23:05:50] <K4ts> night
[23:06:21] <giacus> night
[23:24:18] <jmkasunich> jmkasunich is now known as jmk_away
[23:54:33] <skunkworks> walk with me here. I played with CL today just to look around (very cool) using demo_step_cl
[23:57:39] <skunkworks> I am thinking on how this would work for one of my applications. we have a 62 tool position tool changer. Each tool has a 9 or 12 bit number on them (don't exactly remember). Here is how it normally works. you call a tool say T100. the machine runs the changer reading each tool untill it reads tool 100. it the runs it for 2 more positions until it is over the spindle ready for change.
[23:58:22] <giacus> wow 62 tool position
[23:59:22] <skunkworks> could this be done as it is set using hal and cl without any coding?
[23:59:50] <skunkworks> yes 62 :)
[23:59:57] <giacus> I dont reach 7 tool in all :(