#emc | Logs for 2010-05-19

[00:00:19] <grommit> Where do you mount the magnet on these encoders?
[00:00:52] <Valen> 1-3mm above the center of the chip
[00:01:24] <grommit> on a spinning shaft?
[00:01:32] <Valen> yeah
[00:02:08] <grommit> hmm, I was looking for something for my spindle motor. That might just work...
[00:02:46] <morfic> skunkworks: was that reply to me?
[00:03:45] <Valen> the resolution goes down with RPM
[00:04:00] <Valen> the 8 bit one has a max rpm of 30k
[00:04:19] <Valen> but the number of counts its going to put out at that speed is lower in incremental mode
[00:04:29] <skunkworks> alex has done a lot of work in the interpreter - I just thought the word 'challenge' looked funny ;)
[00:07:42] <JT-Hardinge> sounds like a miniature turret encoder
[00:11:18] <PCW> yep small/cheap absolute encoder also pot replacement
[00:13:27] <JT-Hardinge> the best thing about getting old is you can watch your old favorite movies again for the first time
[00:14:27] <Valen> lol
[00:15:32] <PCW> And you are always meeting new people...
[00:15:51] <JT-Hardinge> lol
[00:16:02] <JT-Hardinge> if only I could remember their names
[00:17:01] <grommit> My spindle motor is connected to the actual spindle though a belt with a smaller pully on the motor, a larger pully on the actual spindle (2:1 - 18teeth vs 36 teeth). If I were to put one of these encoders on the bottom of the motor shaft, and knowing the ratio, would this be good enough to use to do rigid tapping? Or is it essential that the ecoder be on the actual spindle where the tool is?
[00:17:30] <morfic> skunkworks: "alex_joni" alex?
[00:21:46] <PCW> I'm happy, my twiddler module fits in a 5I20 even with 8 servo axis..
[00:21:48] <PCW> time to go home before I break something...
[00:22:24] <grommit> btw, the video at this link cracks me up. We have to have the pretty woman to grab our attention before the Senior Product Marketing Manager appears otherwise we might not watch ;-) http://www.austriamicrosystems.com/eng/Products/Magnetic-Encoders/Rotary-Encoders/AS5134
[00:23:56] <PCW> bait and switch :-(
[00:24:20] <skunkworks> morfic: yes
[00:24:35] <PCW> bye all
[00:24:45] <JT-Hardinge> goodby Peter
[00:24:45] <grommit> bye add thanks Peter
[00:24:49] <grommit> add==and
[00:25:46] <morfic> cnc4pc has fancy looking pendants
[00:26:06] <JT-Hardinge> wow new door seals on both ends of the Hardinge...
[00:26:18] <JT-Hardinge> morfic I've used one of those
[00:26:47] <morfic> any longevity complaints? integrations looks easy enough even for a morfic ;)
[00:26:49] <JT-Hardinge> http://www.linuxcnc.org/docview/html//examples_mpg.html
[00:27:19] <JT-Hardinge> I just tested it then set it to Ray but can't find him to get it back LOL
[00:27:23] <morfic> http://wiki.linuxcnc.org/emcinfo.pl?Hooking_Up_A_MPG_Pendant i found this one
[00:27:26] <JT-Hardinge> set/sent
[00:27:34] <Valen> austria microsytems chick is pretty hawt
[00:28:00] <Valen> rofl at the marketing guys eyebrow
[00:28:19] <JT-Hardinge> the one I linked is the one I wrote after testing the cnc4pc pendant
[00:29:00] <morfic> ah yeah, i read that link earlier too, i recognize the wording :)
[00:29:26] <JT-Hardinge> hillbilly wording:)
[00:29:39] <JT-Hardinge> dang forgot the space :)
[00:31:26] <JT-Hardinge> * JT-Hardinge time for this old dog to hit the lazyboy and flip on the magnetass switch
[00:31:27] <morfic> boss looked at space on door of mori seiki, so pendants came up again
[00:31:36] <morfic> lead ass?
[00:31:57] <JT-Hardinge> steel or the magnet would not work :P
[00:32:10] <morfic> uh huh
[00:32:11] <morfic> :P
[00:32:43] <JT-Hardinge> say goodnight Gracie
[00:46:54] <Jymmm> $11 surface grinder... http://sfbay.craigslist.org/sby/tls/1747849897.html
[00:47:41] <Valen> I'd be in that
[00:51:20] <Jymmm> SWPadnos: Yo, you gots a sparez GPIB IO card?
[01:11:08] <apostrophe> apostrophe is now known as ApOsTrOpHe
[01:31:50] <Jymmm> I got the plotter!!!!
[01:32:49] <Jymmm> The guy used to work for HP, and this one unit is a pre-street version. Even came with 2 user manuals AND the SERVICE manual with diagrams, parts list, and I think schematics!!!
[01:50:26] <ries_> ries_ is now known as ries
[02:47:52] <ApOsTrOpHe> ApOsTrOpHe is now known as apostrophe
[08:29:05] <MattyMatt> DAMMIT SNIPED
[08:32:12] <pjm> what u after MattyMatt ?
[08:32:57] <Jymmm> MattyMatt: We really don't need to know about your order of blow up dolls!
[08:35:25] <pjm> lol
[08:38:46] <MattyMatt> these sets of vextra steppers
[08:39:48] <MattyMatt> I'm up against 2 snipebots
[08:40:53] <MattyMatt> ah well, back to work. all the 2A ones are gone now, except for the 5 phase ones but they've got 9 bids already
[08:41:28] <MattyMatt> I don't have the time or money to figure out a 5 phase driver anyhow
[08:41:45] <MattyMatt> I'll let pfred1 do that first :)
[08:42:51] <pjm> MattyMatt http://www.arceurotrade.co.uk/Catalogue/Stepper-Motors/Stepper-Motors - i bought one of the 220Ncm ones, pretty cheap
[08:43:32] <MattyMatt> yeah these sets were 4x equiv and 3x equiv, or maybe the slightly shorter ones
[08:43:44] <MattyMatt> they went for 21gbp both sets
[08:43:55] <pjm> cheap
[08:44:34] <MattyMatt> If I desperately needed better motors, I'd have pushed it up some more
[08:44:55] <MattyMatt> but I just did a good day's milling yesterday with these ones
[08:45:42] <MattyMatt> all cash must be saved for ballscrews :)
[08:46:18] <MattyMatt> I'm gonna go for some of the slides this place have got tho
[08:55:07] <MattyMatt> they've got one that might just be the rail I've got fitted already, which would be extra handy
[08:56:41] <MattyMatt> this one is riveted to my ballscrew unit
[09:15:16] <MattyMatt> bloody hell nobody sniped the 5 phases
[09:16:07] <MattyMatt> 26 gbp for 4x nema 23 , a 2A 5P, 1A 5P, 2a 2P & 1A 2P
[09:16:21] <MattyMatt> a nice selection
[09:19:54] <Valen> MattyMatt: seen linearmotionproducts2008?
[09:19:59] <Valen> on ebay, pretty cheap
[09:20:13] <Valen> for new ballscrews and slides made to measure
[09:26:16] <Valen> http://shop.ebay.com/linearmotionbearings2008/m.html
[09:29:58] <MattyMatt> not too shabby :)
[09:33:17] <MattyMatt> a single round rail wouldn't do for a quick fix for my flex tho, I'd need to ditch the drawer slide at the top
[09:34:55] <MattyMatt> or turn it 90 deg, so it's stiff axis is tangential to the round rail
[09:35:33] <MattyMatt> these drawer slides are great, but in only one axis
[09:37:54] <Valen> how do people use drawer slides for CnC stuff?
[09:39:01] <MattyMatt> well strictly the drawer slides only work under the table, where they can extend
[09:39:54] <MattyMatt> the others are similar construction, but have a 100mm carriage in 300mm ballrace in 500mm slide
[09:40:51] <MattyMatt> the work OK if you use enough of them
[09:41:17] <MattyMatt> and they are dirt cheap
[09:42:18] <MattyMatt> I'll have figures for flatness of travel, when I can afford a dial gauge :)
[09:42:52] <MattyMatt> and a straight edge
[09:47:34] <MattyMatt> the steel ruler I'm using wouldn't be smooth enough for a dialgauge I don't think. pita aligning it anyhoo
[09:49:53] <MattyMatt> anyway, the drawer slides under the table are the least of my worries on this machine
[09:52:04] <MattyMatt> they do need a lot of support. mine are on 3x3" beams
[09:52:29] <MattyMatt> 1/4" angle iron would be better
[10:24:54] <MarkusBec_away> MarkusBec_away is now known as MarkusBec
[11:59:17] <awallin_> anyone tried the hawkboard ?
[11:59:41] <awallin_> www.hawkboard.org
[12:00:34] <awallin_> looks similar to beagleboard, but cheaper?
[12:03:32] <SWPadnos> I haven't looked at the difference between the OMAP L138 and hte 3530(?) on the beagleboard, but otherwise they look prett ysimilar
[12:05:22] <awallin_> there's a blueboard also...
[12:05:43] <jlmjvm> should you get all of the ubuntu updates after installing the live cd?
[12:06:14] <SWPadnos> in general, yes
[12:06:16] <awallin_> jlmjvm: I don't think there is much critical for emc2 use in the updates, but they don't hurt...
[12:06:44] <jlmjvm> thanks
[12:15:36] <alex_joni> hawk is pretty low power
[12:16:25] <alex_joni> 149.50 BogoMIPS
[12:16:52] <alex_joni> beagleboard: BogoMIPS : 378.14
[12:18:44] <alex_joni> here's another beagleboard: BogoMIPS : 500.97
[12:18:51] <SWPadnos> yeah, I did notice the half clock speed
[12:19:23] <alex_joni> and the CPU is a bit more dumb for the hawk
[12:19:43] <alex_joni> but at today's prices, I think the D510 is the winner in the hawk/beagle competition :D
[12:20:28] <SWPadnos> wow. I ordered some stuff from NewEgg yesterday (including one of those Jetway boards with 12V-only power), and it's arriving today
[12:20:34] <SWPadnos> with no special shipping charges
[12:20:40] <SWPadnos> indeed
[12:20:40] <alex_joni> cool
[12:20:50] <alex_joni> let me know how the jetway is
[12:21:05] <SWPadnos> since you can get an entire PC (including disk and memory) for the price (but not the size and power consumption) of the beagle
[12:21:09] <SWPadnos> will do
[12:24:28] <Andy_M> hi
[12:25:36] <alex_joni> hi
[12:27:03] <Valen> if your going down the minimalist route perhaps that group that had an AVR running gcode is the end result
[12:27:15] <Valen> total cost ~$4
[12:27:52] <Valen> SWPadnos are the jetway boards atom based?
[12:27:57] <SWPadnos> yes
[12:28:10] <Valen> I believe the new atoms with the non 945 chipset are pretty power efficent
[12:28:11] <SWPadnos> http://www.newegg.com/Product/Product.aspx?Item=N82E16813153166
[12:28:46] <Valen> yeah thats an older one, still has the chipset fan
[12:28:56] <SWPadnos> this one is more expensive because it only needs 12V DC power
[12:29:08] <Valen> going for car battery UPS? ;->
[12:29:12] <SWPadnos> I don't think it's all that old. the D510 hasn't been around too long
[12:29:39] <Valen> oh its not "old" as such
[12:29:58] <Valen> its just not the new new stuff lemme see if i can find one
[12:30:18] <Andy_M> Valen, where?
[12:30:38] <SWPadnos> yeah, the NM10 chipset was only released last December
[12:30:56] <Andy_M> the AVR stuff?
[12:31:02] <Valen> oh that
[12:31:04] <Valen> hackaday
[12:31:52] <SWPadnos> note that the subset of G-code that is supports is - erm - quite a *sub* set :)
[12:32:10] <Andy_M> ill go check it... thanks (to check is it good or not)
[12:32:29] <Valen> if you limited the post processor to G1's that wouldn't actually hinder much it seems
[12:32:48] <Valen> most of post processors seem to just spew gobs of G1s and thats it
[12:32:51] <SWPadnos> that makes block processing rate become more important
[12:33:16] <Valen> you can get AVR's up to 90Mhz I believe
[12:33:34] <SWPadnos> you can make them in FPGAs, but you can't buy them that fast (that I know of)
[12:33:49] <SWPadnos> not the 8-bit ones anyway
[12:33:56] <Valen> not 8 bit no
[12:33:57] <Andy_M> interresting to investigate
[12:34:00] <Valen> http://www.atmel.com/dyn/products/param_table.asp?family_id=607&OrderBy=part_no&Direction=ASC
[12:34:13] <Valen> with built in USB
[12:34:20] <Andy_M> http://www.planet-cnc.com/index.asp
[12:34:25] <SWPadnos> yeah, but those aren't $4 ;)
[12:34:27] <Valen> 128kb of ram and half a meg of flash
[12:34:45] <SWPadnos> built in USB and ethernet, even
[12:34:52] <Andy_M> check this... its a RS232 with 115mbps actually
[12:35:52] <Valen> SWPadnos: yeah those 90mips ones are $8
[12:35:54] <Valen> ouch ;-P
[12:36:28] <Andy_M> ...hahaha
[12:37:13] <Andy_M> around 20khz of stepper...20k step/sec
[12:38:10] <Valen> get one with a bunch of PWM outs on it and you are 90% of the way to a 4 axis machine and a total cost of < $100
[12:38:14] <Valen> now thats interesting
[12:38:34] <SWPadnos> yeah, the AVR32 is a good candidate for some of the low level stuff
[12:38:46] <SWPadnos> and that's not $8 system cost, it's $8 for the CPU ... :)
[12:38:56] <SWPadnos> (in 800 qty)
[12:39:32] <Andy_M> nice
[12:39:43] <SWPadnos> at, one of htem is only $5 in 1000 qty
[12:39:45] <SWPadnos> then
[12:39:47] <SWPadnos> m
[12:39:49] <SWPadnos> garg
[12:40:18] <Valen> its an all in one device you only need to give it (a little bit of ) power
[12:40:39] <SWPadnos> and a bunch of caps, I/O protection, a PC board, etc. etc.
[12:40:53] <Valen> which you need anyway on the driver
[12:41:07] <Valen> ok lets be generous, $12 for the AVR ;->
[12:41:22] <Valen> you could still create a 4 axis setup for < $100
[12:41:37] <SWPadnos> sure, you could do that
[12:41:37] <Valen> for say 400W motors (i'm thinking servo here)
[12:41:52] <SWPadnos> maybe
[12:41:53] <Valen> I'm not saying its the best
[12:42:22] <Valen> but a mesa tool chain is $500 for the same thing, its a bit of a barrier to entry
[12:43:29] <SWPadnos> it's not the same thing
[12:43:40] <Valen> no, but it might be close enough
[12:43:48] <SWPadnos> it may perform enough of the same functions, in some cases though
[12:43:53] <SWPadnos> -,
[12:44:21] <SWPadnos> I guess I should mess with my AVR32 development kit today
[12:44:41] <SWPadnos> one of the UC3A-based ones anyway
[12:44:43] <Valen> I'm thinking of making an open source mill based around graphite epoxy, the whole idea being you start with a good bed, and a minimal set of other bits, then you can upgrade them as time/money allows
[12:44:49] <Valen> I got a dragon yesterday
[12:45:10] <Valen> desigining a breakout board for it tommorow, and learning C on friday lol
[12:46:09] <Valen> anyway nighty night
[12:46:28] <Andy_M> :)
[12:46:37] <SWPadnos> see ya
[12:46:38] <Andy_M> nice
[12:47:02] <Andy_M> ok, good luck
[13:08:09] <Andy_M> hi
[13:38:40] <alex_joni> with the difference that you can get running with the mesa toolchain in a couple days/weeks
[13:38:51] <alex_joni> vs. weeks/months/years? for the avr stuff
[13:39:50] <SWPadnos> yeah. there's still no floating point unit in the AVR32 (but they're working on adding one)
[13:40:23] <awallin_> and the atom-boards from intel are cheaper than a beagle/hawk...
[13:40:46] <SWPadnos> note once you add memory, power supply, and disk, but they're still close
[13:40:56] <SWPadnos> s/note/not/
[13:41:32] <JT-Work> dang internet is lumpy today
[13:42:20] <SWPadnos> wow. Atmel now makes a 6-pin microcontroller in a SOT23 package
[13:42:23] <alex_joni> mine is finally fine :D
[13:42:43] <SWPadnos> and an 8-pin UDFN (about the same size), if you need more I/O :)
[13:42:47] <SWPadnos> http://www.atmel.com/pressroom/photos/ATtiny.jpg
[13:42:57] <alex_joni> SWPadnos: remember the strange problem with emails I had?
[13:43:04] <SWPadnos> no :)
[13:43:11] <SWPadnos> oh, maybe
[13:43:23] <SWPadnos> wasn't it called "Outlook"
[13:43:30] <alex_joni> ha :P
[13:44:14] <alex_joni> nope... it was some strange transmission problem
[13:44:21] <alex_joni> data arriving garbled
[13:44:33] <alex_joni> it seems there was a defective optoswitch
[13:44:36] <SWPadnos> oh right, the jpegs that wouldn't email or something
[13:44:38] <SWPadnos> huh
[13:44:52] <grommit> anyone know where I might find hal and ini config for steppers in velocity mode with PID to start from?
[13:44:58] <SWPadnos> nope
[13:45:21] <SWPadnos> actually there's a user who uses that setup, but I don't remember which one
[13:45:40] <grommit> google wasn't overly helpful
[13:46:44] <alex_joni> grommit: most likely you'll have to start from a servo-sim config
[13:46:48] <alex_joni> and add stepgens to it
[13:47:11] <pcw_home> gtom is the first I think (Sebastian had to make some changes to accommodate his setup)
[13:47:13] <alex_joni> but steppers in velocity mode with pid aren't really gonna work well imo
[13:47:26] <alex_joni> pcw_home: for mesa hardware?
[13:47:36] <pcw_home> Yes
[13:47:39] <grommit> yes, and I have mesa hardware
[13:48:34] <alex_joni> well then, it's sorted ;)
[13:48:48] <alex_joni> grommit: at least you know it should be doable .. which is a huge step forward
[13:49:45] <pcw_home> I think gtom had linear scales for feedback and wanted to retain their accuracy
[13:50:36] <grommit> Anyone know gtom's email address? Or should I just post to the list in hopes of rousing him?
[13:50:53] <JT-Work> he hangs out on the forum a lot grommit
[13:51:05] <grommit> ok, I'll keep an eye out for him
[13:51:19] <grommit> thx
[13:51:39] <pcw_home> You might search through the forum postings, his original machine setup questions are there
[13:51:49] <grommit> good idea
[13:52:01] <SWPadnos> http://www.linuxcnc.org/index.php?option=com_kunena&Itemid=20&func=view&catid=10&id=286&limit=6&limitstart=36&lang=polish
[13:52:14] <SWPadnos> err, I guess you don't need the "lang=polish" :)
[13:52:19] <SWPadnos> neither do I, come to think of it
[13:52:34] <JT-Work> grommit: http://www.linuxcnc.org/component/option,com_kunena/Itemid,20/func,view/catid,10/id,223/lang,english/#231
[13:54:59] <JT-Work> cutting left hand threads with g76 is it as easy as just having the start Z on the left side of the end Z? It seems so on a sim...
[13:56:07] <cradek> sure
[13:56:35] <JT-Work> Yea! that makes it easy
[13:56:39] <grommit> thanks for the links...
[14:00:14] <elmo40> ok, this is weird. http://qurl.org/fz0 but I want to see how it tastes ;)
[14:14:09] <Guest295> hi all , is there ready distribution of 10.04 and emc 2.4?
[14:15:03] <renesis> 09:44 < SWPadnos> wow. Atmel now makes a 6-pin microcontroller in a SOT23 package
[14:15:06] <renesis> old
[14:15:13] <renesis> is it actually available yet?
[14:15:22] <renesis> and close to the pic price?
[14:16:40] <renesis> http://search.digikey.com/scripts/DkSearch/dksus.dll?Cat=2556109&k=attiny10
[14:16:49] <renesis> tiny10 = does not exist
[14:18:15] <renesis> and the small pic is like half the price, dunno part number or exact spec though, been around way longer so safe to assume atmel put more mem and flash
[14:19:45] <renesis> damn only 12mhz too
[14:20:11] <renesis> o, right because internal RC is maybe only option, only practical one
[14:20:46] <SWPadnos> right, they're flash parts
[14:21:26] <renesis> 1K prom is pretty good
[14:21:51] <renesis> 32b of sram is kinda weak, but enough
[14:21:59] <SWPadnos> plus 32 registers :)
[14:22:07] <renesis> yes i know
[14:22:12] <renesis> 16 are gimp tho
[14:22:24] <renesis> the last 3 pair make up for it tho
[14:22:39] <renesis> ive done a ton of avr asm =)
[14:22:43] <SWPadnos> you can still do all the math and stuff with them, just no immediate operands
[14:22:47] <SWPadnos> yeah, me too
[14:22:58] <jlmjvm> i did the 2.4 upgrade,cant connect to internet anymore
[14:23:10] <renesis> my fav architecture so far
[14:23:16] <SWPadnos> I have a project that's got ~800k of AVR ASM source
[14:23:20] <SWPadnos> yep
[14:23:31] <renesis> sam7 is neat, good atmel docs, but the dev tools mess kinda killed it
[14:23:32] <SWPadnos> jlmjvm, 2.4 and internet are unrelated I'm sure
[14:23:54] <SWPadnos> I have a few dev kits but never got around to making anything with the SAM7x series
[14:24:13] <renesis> i spent some time coding peripheral interfaces
[14:24:17] <jlmjvm> i agree,but it has done it 2 times
[14:24:18] <renesis> just to learn c
[14:24:33] <SWPadnos> what do you mean that it has done it two times?
[14:24:57] <SWPadnos> two machines upgraded, or two times you've tried to connect to the internet (on the same machine), or something else?
[14:25:00] <renesis> like after youve compiled two times?
[14:25:04] <jlmjvm> both times that i upgraded to 2.4 i lost internet
[14:25:26] <jlmjvm> had to reload the os
[14:25:40] <SWPadnos> did you also update all other packages?
[14:25:40] <renesis> wow shotgun fix
[14:26:02] <jlmjvm> yes
[14:26:23] <atmega> Out for Delivery!
[14:27:07] <renesis> hopefully atmel can keep tiny10 in stock soon
[14:27:23] <atmega> are the 10's actually out?
[14:27:29] <renesis> im afraid to do anything with it because what if i do something cool and need way more
[14:27:49] <renesis> iunno, theyre not in stock at digikey
[14:28:01] <atmega> have you seen one in real life?
[14:28:05] <SWPadnos> jlmjvm, did you update the same machine twice?
[14:28:21] <renesis> but avrisp2 and dragon and xmega (and avr32 but who cares) and some avr have been like this
[14:28:29] <jlmjvm> yes,same machine
[14:28:52] <renesis> like theyll be sporadically stocked at first
[14:28:53] <SWPadnos> ok, next time, do all OS updates and see if you still have internet access *before* updating EMC2 to 2.4
[14:29:06] <jlmjvm> did that this morning
[14:29:23] <SWPadnos> ok, and it works fine with everything up to date except EMC2?
[14:29:29] <jlmjvm> yep
[14:29:39] <SWPadnos> exactly what did you do to update to 2.4?
[14:29:46] <SWPadnos> and what OS version are you using?
[14:29:52] <jlmjvm> the wiki instructions
[14:30:03] <jlmjvm> the last live cd
[14:30:16] <SWPadnos> so 8.04
[14:30:20] <jlmjvm> yes
[14:30:37] <jlmjvm> btw,got 2.4 to work also
[14:30:38] <renesis> atmega: arrow lead time says 10 weeks
[14:30:39] <SWPadnos> and all you did was edit the sources.list to change emc2.3 to emc2.4?
[14:30:53] <renesis> damn they been hyping this chip forever now, theyre lagging
[14:31:03] <SWPadnos> what was the fix?
[14:31:06] <jlmjvm> yes,then reload and mark all
[14:31:34] <SWPadnos> when you did that, was anything other than EMC2 updated?
[14:32:08] <jlmjvm> i think so
[14:32:23] <SWPadnos> aha! :)
[14:32:44] <SWPadnos> like the RTAI kernel, or more stuff
[14:33:54] <jlmjvm> dunno for sure,seems like it had some dependecies
[14:34:59] <SWPadnos> well, the way to tell for sure is to install the OS, run synaptic, reload package lists, mark all/apply, then change the package repo name and update emc2
[14:39:31] <jlmjvm> just wanted to report what happened,will reload os and go back to 2.3.5
[15:09:37] <elmo40> issues with 2.4?
[15:17:28] <eric_unterhausen> possibly just a driver issue?
[15:26:12] <Jymmm> Morning
[15:40:36] <alex_joni> morning jlmjvm
[15:40:39] <alex_joni> morning Jymmm
[15:41:03] <Jymmm> DAMN!!!! http://www.cnn.com/video/#/video/offbeat/2010/05/18/moos.hail.storm.hell.cnn?hpt=C2
[15:41:25] <jlmjvm> alex_joni:morning alex
[15:43:29] <grommit> http://www.youtube.com/watch?v=j1kftCx5-tA
[15:48:19] <motioncontrol> good morning. the 2.4 version not is out ?
[15:51:22] <SWPadnos> well, that's a bummer. the NewEgg description of the Jetway MB is wrong. There are only 3 USB ports on headers
[15:52:33] <Jymmm> Those bastards!
[15:52:37] <SWPadnos> yes
[15:52:56] <DaViruz> 3 as in 3 double for total 6?
[15:53:20] <SWPadnos> no, that's what the description says
[15:53:26] <DaViruz> never seen a usb header with anything else then two ports on it
[15:53:34] <SWPadnos> it's actually one 9-pin dual-port header and one 4-pin single port header
[15:53:42] <SWPadnos> I have :)
[15:53:57] <Jymmm> Rip apart a hub and shove it in there
[15:54:01] <DaViruz> i've at least heard of it (now) :)
[15:54:07] <SWPadnos> yeah, me too
[15:54:18] <SWPadnos> I hadn't seen one before today
[15:54:32] <Jymmm> LOL, Playboy in 3D
[15:54:51] <SWPadnos> it has 8 GPIO pins on a header (with Vcc and Gnd also), which is cool
[15:55:02] <SWPadnos> that's in addition to the parallel port
[15:55:19] <DaViruz> some mini-itx board?
[15:55:27] <SWPadnos> http://www.newegg.com/Product/Product.aspx?Item=N82E16813153166
[15:55:45] <DaViruz> gpio and sometimes spi seems fairly commmon on those
[15:56:04] <SWPadnos> yep, way more common than on an ATX mobo
[15:57:55] <SWPadnos> cool. it's got an RS422/485 port as well (TX and RX differential pairs only though, no modem control signals)
[15:58:52] <DaViruz> one board i looked at when i was shopping for mini-itx, i think it was a jetway too, had four headers for serial ports, all rs232/422/485-capable
[15:59:29] <SWPadnos> hmmm. it looks like this extra 4-pin header is actually part of COM2, but you can select RS422/485 or RS232 for that port in the BIOS
[16:01:19] <Jymmm> SWPadnos: Yo, joooos gotz a sparz GPIB IO card?!
[16:01:34] <SWPadnos> nope. I gotz no GPIB card
[16:01:56] <Jymmm> Really?! Not even one?
[16:02:23] <SWPadnos> nope. never had one
[16:02:25] <pcw_home> Ive got a QBUS one...
[16:02:55] <Jymmm> SWPadnos: I gots me a HP 9872C Flat Bed Plotter =)
[16:03:01] <SWPadnos> I saw that
[16:04:04] <Jymmm> I saw an GBIP to ethernet adapter, but it's $200
[16:04:08] <atmega> I have qbus machines :(
[16:04:24] <SWPadnos> that's cheap. they used to be $1000
[16:04:26] <grommit> The Indel D510MO mini-itx is a nice board (fanless): www.mini-box.com/Atom and it's only $80.
[16:04:30] <grommit> Intel
[16:04:59] <SWPadnos> yep. still has only 3 USB headers (3 ports), which is a problem for me but not many others
[16:04:59] <Jymmm> SWPadnos: http://www.sparkfun.com/commerce/product_info.php?products_id=8841
[16:05:15] <Jymmm> SWPadnos: Go get a 8 port usb hub
[16:05:17] <SWPadnos> the main difference is that the Intel board needs an ATX power supply, but the JetWay only needs 12V in
[16:05:24] <SWPadnos> BZZZT!
[16:05:51] <SWPadnos> http://cgi.ebay.com/NATIONAL-INSTRUMENTS-NI-PCI-GPIB-IEEE-488-2-CARD-/280506143249?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item414f781211
[16:06:00] <grommit> true but that power supply is tiny!
[16:06:26] <SWPadnos> it's $30 or more, closer to $50 for a PicoPSU (which still needs the 12V supply)
[16:07:01] <grommit> true that
[16:08:44] <grommit> btw, https://mini-box.com/Jetway-NF6-510-mini-ITX has the correct specs on your board, fwiw...
[16:09:04] <SWPadnos> so do I, now :)
[16:09:08] <grommit> :-)
[16:09:10] <Jymmm> SWPadnos: Doesn't look like a GPIB connector to me... http://sfbay.craigslist.org/sby/sys/1746584263.html
[16:09:36] <SWPadnos> that's not a GPIB connector
[16:09:46] <Jymmm> echo echo
[16:09:49] <SWPadnos> it looks like the description is for two cards but only one is pictured
[16:12:10] <Jymmm> I emailed him, we'll see.
[16:12:48] <Jymmm> SWPadnos: Yeah, I even got the service manual too.
[16:12:59] <SWPadnos> yep, that's cool
[16:13:15] <Jymmm> Man, they SERIOUSLY did some awesome documentation back then
[16:13:43] <Jymmm> PN, vendors, drawings, etc
[16:14:28] <isssy> hi
[16:14:44] <isssy> is there rt kernel for ubuntu 10.04?
[16:16:06] <Jymmm> SWPadnos: A mobo with RS422 built in?!
[16:16:15] <SWPadnos> yep
[16:16:18] <Jymmm> WOW
[16:16:47] <SWPadnos> only one port though, and it's just RX/TX that change, the other signals are left as single-ended RS232
[16:17:09] <Jymmm> ah
[16:17:53] <grommit> anyone have a favorite source for inexpensive, small 5VDC supply (110AC in, 2A or so)?
[16:18:06] <Jymmm> My junk box
[16:18:09] <bill2or3> broken gadgets.
[16:18:10] <elmo40> 10GBase-T is on its way. Too bad fibre is faster and less expensive ;)
[16:18:12] <grommit> send one over
[16:18:34] <Jymmm> grommit: I'll fax it to you
[16:18:37] <SWPadnos> Radio Shack isn't all that bad, but I don't know if they still have a 2A model
[16:18:39] <grommit> cool
[16:19:05] <Jymmm> SWPadnos: You'll get raped on any walwort these days
[16:19:23] <elmo40> walworts max at 1A, I believe
[16:19:24] <eric_unterhausen> marlin p jones has power supplies, or midwest surplus
[16:19:40] <Jymmm> elmo40: Nope, I have some 5A ones (switchng)
[16:23:03] <eric_unterhausen> that's because wallworts can be used to make beer, it's the alcohol taxes
[16:23:17] <eric_unterhausen> wall warts on the other hand, are a dime a dozen
[16:25:17] <elmo40> Jymmm: walworts? interesting.
[16:25:50] <elmo40> out of all of mine I have seen a max of 1A @ 12V
[16:26:18] <eric_unterhausen> elmo, do you care if it's switching?
[16:26:40] <elmo40> ahh, fibre networking... 100Gb/s <drools>
[16:26:52] <SWPadnos> I don't think I've seen any that plug directly into the wall that are higher than about 2A, but there are definitely a bunch that have cords that are several amps (I have a 5V 5A one from a DSP development kit)
[16:26:55] <elmo40> eric_unterhausen: I am not looking for one ;) only making a comment
[16:27:21] <SWPadnos> but it's more like a laptop power brick
[16:27:22] <grommit> I want to mount it to a plate inside a chassis, so would rather not have a wart
[16:27:34] <elmo40> if I wanted 5 or 12V I would rip apart a computer power supply :)
[16:27:43] <Jymmm> I save every walwort I come across anymore. At $15/ea just too expensive not to.
[16:27:48] <grommit> could do that, I might have some junk around...
[16:27:54] <SWPadnos> then you should get a DIN-rail mount one, but you'll have to give up "inexpensive"
[16:28:15] <elmo40> Jymmm: $15? wow, that is expensive. the local surplus place here has them for $2 - $5
[16:28:16] <grommit> I saw those, and they do look nice, but yes, not inexpensive
[16:28:31] <SWPadnos> http://www.radioshack.com/product/index.jsp?productId=2049709&filterName=Category
[16:28:34] <MattyMatt> unless you mill the DIN rail clips into your one
[16:28:44] <SWPadnos> close enough maybe? (6V 1/8A, $1.47)
[16:28:49] <SWPadnos> err, 1.8A
[16:29:16] <Jymmm> It's being doscontinued
[16:29:21] <Jymmm> Discontinued
[16:29:25] <SWPadnos> of course. get 6 :)
[16:29:25] <MattyMatt> nokia phones are 5V, but iirc 700ma is the biggest I've seen
[16:29:59] <Jymmm> Any time you see a RS price ending in 7 or 8 means it's discontinued and clearance
[16:30:07] <Jymmm> s/and/or/
[16:30:16] <MattyMatt> grabbag
[16:30:24] <grommit> my local RS stores say they don't have that one...
[16:33:19] <MattyMatt> I got an usb/ide adaptor that came with a neat 12/5 psu
[16:34:17] <SWPadnos> http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=945-1075-ND
[16:35:08] <grommit> funny i was just searching digikey
[16:35:20] <SWPadnos> http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=285-1745-ND
[16:35:37] <SWPadnos> that may be closer to what you're looking for
[16:35:50] <SWPadnos> higher power than you need though
[16:40:48] <Jymmm> SWPadnos is the DigiKey search King!!!
[16:40:54] <SWPadnos> heh
[16:41:07] <SWPadnos> come on, they only have 362000000 part numbers ...
[16:41:29] <Jymmm> Their search sucks
[16:41:40] <SWPadnos> I love it
[16:42:31] <Jymmm> goto the main page and at the top type in "LED"
[16:42:35] <SWPadnos> hmm. actually I should use that power supply in a project I'm doing
[16:42:37] <DaViruz> farnell search <3
[16:42:57] <SWPadnos> Jymmm, yeah, and then select what kind of LED-related thing you want
[16:43:06] <Jymmm> SWPadnos: a fan!?
[16:43:16] <Jymmm> Oh yeah, a rivet has an led
[16:43:17] <Jymmm> NOT!
[16:43:19] <SWPadnos> drivers? backlights? LCDs? SMT LEDs? ...
[16:43:33] <Jymmm> No go look it brings rivets
[16:44:00] <SWPadnos> so, you know you don't want rivets (or buzzers, battery holders ...)
[16:44:08] <SWPadnos> so don't click those categories
[16:44:26] <Jymmm> so if I serach for LED, dont' show me rivets damnit!
[16:44:59] <elmo40> type Diode :P
[16:45:21] <bill2or3> * bill2or3 searches for "not rivets"
[16:45:24] <Jymmm> Nah, I just tell SWPadnos and let him search for me
[16:45:34] <SWPadnos> but what if the rivets are "dimpled" or something? :)
[16:46:30] <Jymmm> does it have/hold an LED ?
[16:46:37] <Jymmm> and intended to do so?
[16:47:09] <SWPadnos> clearly you don't understand what text search is ;)
[16:47:44] <Jymmm> I clearly understand they didn't consider such a simple search
[16:47:50] <SWPadnos> of course, I don't actually see the text "led" in the descriptions :)
[16:48:19] <SWPadnos> I guess I don't care if they show me more stuff than I'm looking for at first, since it's so easy to narrow it down later
[16:49:15] <SWPadnos> ah, Nylon, Glass fil[led]
[16:49:27] <Jymmm> No, what that is a is a general category listing. They use that as the default when the search exceeds a certain count, like 10K+
[16:49:43] <SWPadnos> nope
[16:49:48] <Jymmm> yep
[16:49:58] <SWPadnos> it still only lists items that match your search
[16:50:07] <Jymmm> RIVETS?!
[16:50:23] <SWPadnos> there are 5 rivets that have the text LED somewhere in their data
[16:50:31] <Jymmm> prove it
[16:50:53] <cradek> "these rivets led to my demise"
[16:51:01] <Jymmm> lol
[16:51:04] <SWPadnos> well, I looked at one of the descriptions, from the list of 5 items presented to me when I clicked "rivets"
[16:51:24] <SWPadnos> if I search for "rivet", there are 366 items in the "Rivets" category
[16:51:35] <SWPadnos> so clearly they are using my search text
[16:51:44] <Jymmm> and there are 61K for 'led'
[16:51:54] <SWPadnos> they have a shitload of different LED part numbers
[16:52:07] <SWPadnos> try "cap" or "res"
[16:52:42] <Jymmm> No, you show me. I search for LED you dont give me rivets bastards!
[16:52:48] <SWPadnos> "Chip Resistor - Surface Mount (210,861 items)"
[16:53:00] <SWPadnos> searching for "res"
[16:53:30] <SWPadnos> you could also type more, like "red led"
[16:54:10] <celeron55> probably best is to include the package name in the search
[16:54:14] <celeron55> or something like that
[16:54:19] <SWPadnos> yeah, that's a big help
[16:54:40] <Jymmm> Maybe I don't know what color I want, maybe I want to se what's available, give me a list and then I can narroow it down from there.
[16:54:46] <SWPadnos> I guess it's the difference between an index and a menu. DK is a very easily searched index, but it's not a menu
[16:55:47] <celeron55> Jymmm: try farnell.com to see what's available and then search other places for the cheapest price :-)
[16:55:50] <celeron55> that's what i do
[16:56:21] <celeron55> also mouser.com has a similar index
[16:56:22] <SWPadnos> the best search would probably be a combination of McMaster and DigiKey
[16:56:27] <celeron55> (probably larger)
[16:56:45] <SWPadnos> McMaster has a nice visual menu, but DigiKey lets you select multiple categories simultaneously
[16:56:56] <SWPadnos> combine those and it would be a real winner
[17:04:45] <Jymmm> Y'all are just WAY TOO COMFORTABLE with mail ordering stuff
[17:05:44] <MattyMatt> it keeps the mailman employed
[17:05:56] <MattyMatt> * MattyMatt drops litter
[17:06:08] <MattyMatt> and that keeps the sweepers in work :)
[17:06:40] <DaViruz> digikeys site feels like a return to the 1990's to be honest
[17:06:58] <DaViruz> ans while that can be good in a lot of cases, that's not what i had in mind now
[17:07:09] <MattyMatt> somebody on #reprap wanted to know a plastics supplier in EU, so I suggested his local yellow pages
[17:07:16] <Jymmm> DaViruz: or 1890's =)
[17:07:36] <SWPadnos> Here's a great line from a power supply manual:
[17:07:43] <SWPadnos> After it delivers it, I will repair three years free of charge for an
[17:07:45] <SWPadnos> emergency breakdown. However, because handling is careless, it becomes for a fee.
[17:08:15] <celeron55> quality translation
[17:08:30] <SWPadnos> "The short-circuit leaving for a long time doesn't cause the breakdown and do not do, please."
[17:08:52] <DaViruz> wow, usually you can at least make out what they mean
[17:09:51] <MattyMatt> I still haven't had my Machining In Polsk lesson from yoyoek yet
[17:10:21] <MattyMatt> I think I'll convert all his GUI to poloish, and see how he likes it :)
[17:13:58] <MattyMatt> actually a careful read of his docs will probably give me the clues I need
[17:15:46] <MattyMatt> and I have ballmills now, so I can try it out for real
[17:17:55] <MattyMatt> 3 ballmills and 2 eyeballs, despite my efforts today. These 2 flutes don't crush their way through anything like the 4 flute does
[17:18:02] <gweepprefect> SWPadnos: my favorite bizarre translation from a power supply was for a redundant supply for a server which claimed that "when both supplies are working properly they will go Dutch the loading"
[17:18:47] <SWPadnos> heh
[17:19:26] <celeron55> :D
[17:19:33] <Jymmm> wooden shoes in a PS ???
[17:20:02] <MattyMatt> klompenhout \o/
[17:20:21] <skunkworks> heh - go dutch - that actually makes sense.
[17:20:26] <MattyMatt> first thing I'm making when I've got 5 axes
[17:21:14] <Jymmm> MattyMatt: Um, why?
[17:21:39] <Jymmm> MattyMatt: Now, if you WEAR them, send us pics!!!!
[17:22:08] <MattyMatt> I'll need them if I start casting
[17:23:27] <MattyMatt> I had a good pair of boots that both soles fell off, together on cue. I just need wooden soles on them
[17:23:41] <Jymmm> WTF?! you cn't put "Entry level" and "Ninja" in the same job desc. The cheap bastards! http://sfbay.craigslist.org/sby/mar/1748857871.html
[17:26:01] <MattyMatt> they are spammers, after all
[17:26:10] <Jymmm> "Root Beer Pong" ?!
[17:26:37] <MattyMatt> it's a student drinking game
[17:26:52] <Jymmm> I know what it is, but it aint with root beer!
[17:27:31] <MattyMatt> so, lying spamming bastards
[17:27:47] <MattyMatt> $40k a year? I'm there dude
[17:28:08] <MattyMatt> * MattyMatt returns after a year
[17:28:19] <Jymmm> Well, they do say it's a marketing job, I guess they are trying to sling their own shit, but it aint sticking to the wall!
[17:28:23] <MattyMatt> they paid me these 5 beans, but they said they are magic
[17:28:52] <Jymmm> MattyMatt: No it's $30K-40K
[17:28:54] <MattyMatt> DIRECT marketing, aka spam
[17:30:23] <Jymmm> No, I think it's door-to-door sales... http://northerncaliforniagroup.com/FAQ.html
[17:30:35] <Jymmm> like pizza flyers
[17:31:05] <MattyMatt> junk mail is spam, IMO
[17:31:21] <eric_unterhausen> multi-level marketing, i.e. a pyramid scheme most likely
[17:31:39] <Jymmm> 1. What does The Northern California Group do?
[17:31:39] <Jymmm> We are outsourced by major clients to increase their market share through the acquisition of small to medium size business customers on their behalf. We meet directly with these customers, and through face to face, relationship oriented sales, are able to consult their business needs while increasing our clients customer base.
[17:33:26] <MattyMatt> the business business
[17:34:36] <MattyMatt> this is why I like internet shopping, it cuts out middlemen
[17:59:43] <Jymmm> MattyMatt: But when you have a problem, there's nobody to strangle!
[18:12:37] <sealive> is there a doco how to compile emc2 on a ubuntu 9.10karmic amd64 only axis no realtime?
[18:15:24] <micges> sealive: http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Installing_EMC2#Pre_requisites_for_Ubuntu_9_10
[18:15:53] <Jymmm> M.I. Squirrel http://v6.tinypic.com/player.swf?file=sloeix&s=6
[18:15:56] <SWPadnos> yep, just follow section 2.4 and 2.6
[18:16:44] <sealive> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Installing_EMC2#Building_emc2_simulator
[18:16:55] <sealive> this is what iam searching for
[18:17:08] <sealive> but i made a big miss
[18:17:25] <sealive> iam on karmic and a did delete the python2.5
[18:17:41] <sealive> now i'am in big trouble
[18:18:00] <SWPadnos> sudo apt-get install --reinstall python2.5
[18:18:14] <SWPadnos> (or something like that, look at the man page)
[18:19:12] <sealive> apt does use python 2.5
[18:19:25] <sealive> so iam pisst off as the americans say
[18:19:39] <sealive> german Da beist sich die katze in den schwanz
[18:19:53] <SWPadnos> somewhere in /var/apt/cache or similar will be the packages you have installed
[18:20:08] <SWPadnos> go there, then use dpkg instead (which may not depend on python, but I don't know)
[18:20:22] <SWPadnos> dpkg -i <the name of the python package>
[18:20:35] <sealive> i go to ubuntu and see what i can do
[18:20:53] <sealive> you are wright dpkg does not use python
[18:21:09] <SWPadnos> synaptic may also be able to do it
[18:21:19] <sealive> no
[18:21:23] <SWPadnos> especially if you use the CD-ROM as a package source
[18:21:25] <SWPadnos> oh
[18:21:32] <sealive> synaptic wars the first that colust
[18:21:39] <sealive> thet went off
[18:22:03] <sealive> ok i try
[19:19:29] <davidf> Hi, I want to be able to use G76 canned cycle threading on my little 7 x 12 retro'd lathe. I have an open loop stepper system with emc2. Is all I need just a spindle index pulse? I'm guessing that a spindle encoder signal would be useless in the case of an open loop stepper system. Is that right? - TIA for anyone's help!
[19:21:59] <mikegg> some one correct me if I'm wrong, but I think you need an encoder signal all the way around
[19:22:19] <mikegg> EMC will slave the motion of your X axis to whatever the spindle is doing
[19:22:50] <mikegg> the fact that X is open loop really doesn't matter
[19:23:33] <SWPadnos> you can use an index pulse only, but an encoder is better
[19:23:45] <SWPadnos> the type of axis motors you have is irrelevant
[19:23:59] <davidf> Oh thanks.
[19:24:26] <SWPadnos> did you use stepconf to set up your machine?
[19:24:51] <davidf> So the z motion will thrack variations in spinde speed regardless huh? I think I get it now.
[19:25:07] <davidf> SWPadnos, yes.
[19:25:16] <SWPadnos> yes, you get better synchronization the better the encoder resolution
[19:25:25] <SWPadnos> and 1PPR is pretty low resolution :)
[19:25:46] <davidf> HAha yes it is.
[19:25:49] <SWPadnos> ok, you can select a parport input as "Spindle encoder phase Z"
[19:26:10] <SWPadnos> I don't think there's an option for phases A and Z, but if there is, that's a better option to use
[19:26:41] <SWPadnos> assuming there isn't, you need to add something like the following to your custom.hal (and make sure the checkbox to use a custom hal script is checked)
[19:27:01] <SWPadnos> net spindle-phaseZ encoder.0.phase-A
[19:27:30] <SWPadnos> setp encoder.0.counter-mode 1
[19:28:01] <SWPadnos> (that may be called count mode, and the signal may not be called spindle-phaseZ, you'll need to check those)
[19:28:19] <SWPadnos> oooh. I may get dropped here, back in a bit if so
[19:28:30] <davidf> I think I found the right doc for this: http://www.linuxcnc.org/docs/devel/html/examples_spindle.html#cha:Spindle-Feedback
[19:29:28] <SWPadnos> yep. using stepconf will add a lot of that for you
[19:30:49] <davidf> OK. I think I will try and make an encoder. I checked the price of one online, $300 - $500 - that seems awfully high. Any suggestion for a cheap ready made one?
[19:31:03] <SWPadnos> ebay
[19:31:37] <SWPadnos> or, if you can make a 1:1 belt drive (absolutely must be 1:1, you can only have one index per revolution), you can use the AMT-109
[19:31:41] <SWPadnos> available from DigiKey
[19:31:47] <SWPadnos> $29 or something
[19:32:19] <grommit> why must it be 1:1?
[19:32:35] <SWPadnos> because you may only have exactly one index per spindle revolution
[19:33:11] <SWPadnos> http://search.digikey.com/scripts/DkSearch/dksus.dll?Cat=1966131&k=amt
[19:33:21] <davidf> Awesome. I have plenty of gears on the back available with room to add a jack shaft and encoder. I guess I'd just need a litthe friction to eliminate backlash - does that sound ok to you?
[19:33:46] <grommit> reason I ask is that I have a 2:1 belt on a spindle and wanted to put an encoder on it, but there is only room to put it on the spindle motor shaft, and not the actual tool spindle running at 1/2 the motor speed
[19:34:04] <SWPadnos> a small belt drive would be fine. just make sure you use only the final spindle gear, you can't base the index off some other ratio
[19:34:28] <SWPadnos> grommit, that won't work well for threading or other spindle synchronized motion
[19:34:34] <grommit> bummer
[19:34:49] <SWPadnos> you could always gear the encoder down by 2:1
[19:35:02] <SWPadnos> so it's the same as the spindle
[19:35:19] <grommit> oh, hmm so it isn't on the actual spindle but it on a phantom spindle, as it were....
[19:35:28] <SWPadnos> but I'd only do that if the spindle is driven from a gear/tooth system, not any kind of friction system that might slip
[19:35:51] <grommit> It is a friction system, and I suppose it could slip (belt)...
[19:36:03] <SWPadnos> right, the requirement is that the index happens once per spindle revolution, if you gear it 2:1:2, that should be fine
[19:36:16] <SWPadnos> ok, then it's not a great idea
[19:36:25] <grommit> until it slips
[19:36:27] <grommit> yeah
[19:36:35] <SWPadnos> it'll probably work fine most of the time, but it's the times it doesn't work that you really would have needed it
[19:36:51] <grommit> right! for threading.
[19:37:11] <SWPadnos> for threading when the load on the spindle causes some belt slip
[19:37:19] <grommit> back to the drawing board on that one (again)...
[19:37:22] <SWPadnos> heh
[19:38:41] <grommit> any kinds of encoders that fit on tool holders?
[19:39:02] <SWPadnos> none that I know of
[19:39:10] <SWPadnos> except a tach
[19:39:16] <grommit> market opportunity :-)
[19:39:17] <SWPadnos> optical/laser type
[19:39:59] <grommit> Someone said that tachs wouldn't be accurate enough to do tapping
[19:40:26] <SWPadnos> you need an index pulse, and it's ideal to have better resolution, such as an encoder would provide
[19:40:39] <SWPadnos> but you can use a single index "flag" and an optical detector if you want
[19:40:50] <SWPadnos> or a laser on a flat spot, like a tacj
[19:40:52] <SWPadnos> tach
[19:41:12] <SWPadnos> you don't want to use the tach itself, but you can use the method they use to get your index pulse
[19:42:30] <grommit> So I would have 1ppr.
[19:42:41] <SWPadnos> yep
[19:43:07] <SWPadnos> if you don't take massive cuts, and/or you do several finish passes, you should get reasonable results
[19:43:30] <davidf> http://members.shaw.ca/swstuff/spindle-encoder.html
[19:43:47] <davidf> Home-made encoder
[19:44:28] <grommit> nice
[19:47:32] <davidf> SWPadnos, I have a gear right on the spindle I can use. As for backlash, does G76 ever have to reverse the spindle direction? If not, just a little drag on the encoder should eliminate any backlash issues, right?
[19:47:50] <SWPadnos> no idea :)
[19:48:12] <SWPadnos> I don't think a lathe spindle ever gets reversed in a canned cycle, but I wouldn't bet you dinner on that
[19:48:35] <SWPadnos> (just because I don't know, not because I think reversals are common)
[19:48:53] <davidf> OK. If I have to, I can add a timing pulley and belt.
[19:49:13] <SWPadnos> you may be able to use the gear directly, incidentally
[19:49:55] <SWPadnos> similar to this method: http://pico-systems.com/bridge_spindle.html
[19:50:04] <davidf> Yeah I thought of that, but it is only like 40 teeth. I guess I could get 160 ppr with quadrature though...
[19:50:14] <SWPadnos> 40 is way better than 1
[19:50:27] <SWPadnos> at least 40 times better! :)
[19:52:40] <celeron55> linear betterness
[19:55:18] <grommit> hmm, that link gives me some ideas for my drawing board...
[19:56:33] <davidf> Just looked at that gear encoder. Very cool. Are those sensors magnetic?
[19:57:35] <SWPadnos> yes, I think those are (the ones Jon E used)
[19:59:58] <davidf> For high quality 40 TPI threads any opinion as to how many counts per rev would be enough?
[20:00:29] <skunkworks> as many as your hardware can count...
[20:00:32] <skunkworks> ;)
[20:00:39] <skunkworks> at the speed you require...
[20:01:44] <SWPadnos> that's a hard question to answer. it depends on how beefy your spindle is relative to the cuts you expect to take
[20:03:10] <grommit> SWPadnos: another smallish 5v pwr sup. reasonably inexpensive: http://www.trcelectronics.com/Meanwell/rs-15-5.shtml
[20:03:33] <SWPadnos> oh. nice one
[20:06:23] <davidf> SWPadnos, so the main thing is light cuts mean less perturbation of the spindle speed which means I can maybe get away with lower resolution? Do I have a handle on this?
[20:06:32] <SWPadnos> yes, I think so
[20:07:16] <SWPadnos> just make sure to use the position-estimate output from the encoder, not position
[20:08:49] <davidf> What is that, a HAL thing or a hardware lead thing?
[20:09:54] <davidf> position-estimate output from the encoder??
[20:10:15] <SWPadnos> the encoder counter has a position output that only tracks actual encoder state changes
[20:10:41] <SWPadnos> and another output that estimates the current position, taking into account the timing between the last detected edge and "now"
[20:10:53] <SWPadnos> you need the less lumpy one, the estimate
[20:11:08] <davidf> This is in software, right?
[20:11:22] <SWPadnos> yes, it's the use of one HAL pin instead of another
[20:11:34] <davidf> Got it.
[20:12:30] <davidf> SWPadnos, what a lot of helpful stuff. Thanks!
[20:12:37] <SWPadnos> sure
[20:27:23] <Jymmm> Dude, it's called sandpaper, paint, and dont leave it in the back of your truck in the winter time! http://sfbay.craigslist.org/sby/tls/1749284288.html
[20:29:58] <celeron55> or even 1 minute with a pressure washer
[22:24:14] <alex_joni> g'night all
[22:24:22] <bill2or3> sleeps