#emc | Logs for 2010-05-20

[00:22:16] <pjm> pjm is now known as 31NAATOE9
[00:23:09] <pjm> pjm is now known as Guest72459
[01:21:10] <John_f_> This was in a lot of stuff at an auction. http://imagebin.ca/view/yyd94-z.html The placard says "Racine Scew Works Drillmore 3" . It has been modified into some kind of tool. Any Idea on what the original use was?
[01:25:23] <jlmjvm> where r the sample configs in ubuntu 8.04
[01:34:37] <tom3p> /etc/emc2/sample-configs dont ask me why
[01:34:56] <cradek> in 2.4 they are moved to /usr/share/something/whatever/sample-configs
[01:40:44] <jlmjvm> my etc/emc2 folder doesnt have sample configs
[01:42:11] <cradek> jlmjvm: use the power of apt: dpkg -L emc2
[03:10:23] <spasticteapot> Does EMC play nice with Autodesk Inventor?
[03:29:18] <Valen> you need some sort of cam system for it, i dont know if autodesk ships with that
[05:16:59] <elmo40> wow. Encoders are pricey! http://qurl.org/gz0 and http://qurl.org/hz0
[05:18:31] <elmo40> plus, is this even a good price for 'as-is' components? http://qurl.org/iz0
[05:21:45] <elmo40> I wonder how little power this motor produces http://qurl.org/jz0
[05:25:11] <elmo40> now this looks like a great encoder for a Lathe. http://qurl.org/kz0
[05:41:45] <Lerman_> Lerman_ is now known as Lerman
[06:34:22] <Lerman_> Lerman_ is now known as Lerman
[07:03:17] <pingufan> .
[07:09:00] <MattyMatt> elmo40, if you have a lathe and a dividing head, couldn't you make an optical encoder?
[07:12:10] <MattyMatt> with a disk as large as that heidenhain one, it's not superfine work
[07:12:45] <MattyMatt> (says the woodworking man)
[07:27:46] <pingufan> Hi, I had a look on EMC more than one year ago. I was very impressed. Until now I didn't find enough time to finish the drivers for my CNC mill, so I didn't start using it until now. Which costs must I estimate for a cheap bur working 3-axis drive for bipolar steppers? 2 (max. 3 Amps)
[07:28:06] <pingufan> Does somebody pherhaps have a used drive for me?
[07:33:18] <pingufan> I also think about using USB->IDE converters as i do not need high speeds. Does this principally work, or can I forget that?
[07:33:48] <eric_unterhausen> I know someone that does that with ubuntu
[07:33:53] <eric_unterhausen> but not with emc
[07:34:47] <pingufan> Too timing critical, or no hardware support for that?
[07:34:58] <eric_unterhausen> usb disk drives have been known to cause latency problems in the past, hard to predict
[07:35:11] <eric_unterhausen> depends on your motherboard
[07:41:23] <pingufan> You know, I am talking about the connection between EMC and the mill ...
[07:41:51] <eric_unterhausen> that's probably not going to work due to latency
[07:42:41] <pingufan> I see. Do you know a cheap 3-axis controller/driver I could use?
[07:43:44] <eric_unterhausen> I'm not an expert on cheap steppers, I usually just buy from ebay
[07:44:17] <frysteev> morning
[07:44:32] <frysteev> anyone alive this am?
[07:44:40] <pingufan> something you could recommend?
[07:45:19] <eric_unterhausen> I always thought geckos were cheap, so I'm probably not a good person to ask
[07:46:14] <frysteev> i use cncgeeker.com
[07:47:00] <awallin> switch to servos and don't look back. that's my recommendation :)
[07:47:42] <pingufan> :)
[07:49:58] <pingufan> This is an old CNC mill I bought with burned out electronics. But mechanics is very rugged, I love it.
[07:50:42] <frysteev> i hopped in here to ask something. but we figured it out.
[07:50:54] <frysteev> late night session. emcing the laser..
[11:44:55] <elmo40> so, let me get this straight... 'pingufan' has an old CNC mill with burnt electronics and he wants cheap stepper boards?
[11:45:01] <elmo40> why are people SO cheap?
[11:46:30] <herron> wife and kids probably or no job
[11:48:41] <elmo40> lol, wife&kids :-P
[11:48:55] <elmo40> I do too! but I want GOOD components that will last me more then a year.
[11:54:58] <JT-Dev> or at least components that will work
[12:12:25] <JT-Dev> dang this CoolerMaster power supply is heavy
[12:21:32] <JT-Dev> wow the USB 3.0 ports on the mobo are blue
[12:47:26] <JT-Dev> oh this sucks the standoffs are not tall enough to put the plugs in the correct positions :/
[12:47:58] <mozmck> JT-Dev: What board did you get
[12:47:59] <mozmck> ?
[12:48:40] <JT-Dev> Asus M4A87TD EVO
[12:49:37] <jlmjvm> E: dpkg was interrupted, you must manually run 'dpkg --configure -a' to correct the problem.
[12:50:22] <mozmck> I just got a biostar ta890fxe with one of the new 6-core processors. Haven't had much time to play with it yet but it seems to run 10.04 fast!
[12:50:38] <jlmjvm> tried to load adobe flash,now i get this
[12:51:46] <JT-Dev> I got an AMD Athlon II X4 635 2.9 GHz quad core for this one
[12:54:08] <JT-Dev> well I guess I'll just make some new standoffs on the Hardinge :)
[12:56:41] <JT-Dev> * JT-Dev is off to work
[13:12:10] <elmo40> mozmck: I would hope 6-cores would make even win vista run fast!
[13:12:52] <elmo40> now then, you better have at least 1GB of RAM per CPU ;)
[13:24:44] <elmo40> Pidgin 2.7.0 is out :)
[13:25:57] <elmo40> " - "
[13:27:33] <mozmck> elmo40: I might, but this computer won't be contaminated with that virus :)
[13:27:49] <elmo40> which one? vista or pidgin
[13:27:50] <elmo40> :P
[13:27:58] <elmo40> only making a comment.
[13:31:56] <elmo40> great solo piano stream - http://scfire-dtc-aa03.stream.aol.com:80/stream/1004
[13:39:39] <mozmck> elmo40: vista that is :) I like pidgin - way better than Empathy.
[13:40:51] <elmo40> much improved over Gaim
[13:41:18] <elmo40> still needs both audio&video for msn, yahoo
[13:55:17] <elmo40> does jabber support audio/video?
[13:58:14] <elmo40> SWPadnos: a spindle encoder is only useful if you have a good spindle motor? I guess what I mean to ask is, can I use my regular 3/4 Hp motor driving my lathe (via different pulley ratios) and use the encoder at a 1-to-1 on the spindle to cut threads?
[13:58:33] <cradek> yes that works fine
[13:58:39] <SWPadnos> a spindle encoder is most useful when your motor isn't so great, actually :)
[13:58:43] <cradek> emc doesn't care what kind of motor you have
[13:58:55] <SWPadnos> since that's when you need the higher update rate
[13:59:20] <elmo40> at the moment I can't make EMC turn on the motor (no relays yet)
[13:59:41] <elmo40> so the encoder is the only way for EMC to know it is running.
[13:59:54] <grommit> On topic (for once :-)... what kind of resolution is needed to to reasonable tapping ?
[14:00:12] <SWPadnos> grommit, it depends :)
[14:00:38] <SWPadnos> a few hundred PPR and up is probably best
[14:00:46] <elmo40> with the encoder would Axis display my RPM via measuring the PPR ?
[14:00:46] <grommit> I read a long thread from a year or so ago where tapping and encoders was discussed and how important the index pulse is to get before the tap goes in
[14:01:40] <grommit> a few hundred total (even with quadrature)?
[14:01:44] <SWPadnos> elmo40, axis won't directly (I don't think), but you can easily add an RPM readout to a pyvcp panel
[14:01:58] <elmo40> I was going to make one per degree (if I have space)
[14:02:26] <grommit> I have a 36 tooth gear and the only way I think to get encoder is to use a magnetic one (like in the link posted yesterday). So I would only have 36 X 4
[14:02:29] <SWPadnos> grommit, a few hundred total, so a 100CPR (=400 in quadrature) is probably enough, but higher is better (until you start getting into signal quality and count rate issues)
[14:02:34] <elmo40> SWPadnos: just wondering how it would 'know' how fast to move the tool for a given thread pitch.
[14:02:50] <SWPadnos> axis doesn't move the tool, it's just a GUI
[14:03:16] <SWPadnos> you would need to connect the encoder output to the spindle speed input on the motion controller
[14:03:17] <elmo40> ok. what does the counting?
[14:03:18] <SWPadnos> in HAL
[14:03:24] <elmo40> ok
[14:08:27] <elmo40> I want to use the lathe setup from the link that davidf posted: http://members.shaw.ca/swstuff/spindle-encoder.html
[14:08:45] <elmo40> 360 slots on a wheel. should be plenty of resolution
[14:10:05] <elmo40> he has 3 pick-ups. that makes it 1080 PPR ?
[14:11:30] <SWPadnos> 2 for quadrature + index, I'm betting
[14:11:41] <SWPadnos> 1440 PPR
[14:14:11] <pcw_home> Yes you an see one of the holes is elongated for index
[14:14:40] <pcw_home> (can see)
[14:15:17] <ChanServ> [#emc] "This is the #emc channel - talk related to the Enhanced Machine Controller and general machining. Website: http://www.linuxcnc.org/, wiki at http://wiki.linuxcnc.org/"
[14:15:52] <ChanServ> [#emc] "This is the #emc channel - talk related to the Enhanced Machine Controller and general machining. Website: http://www.linuxcnc.org/, wiki at http://wiki.linuxcnc.org/"
[14:16:04] <JT-Work> I see the index pickup is mounted a bit farther back than the other two
[14:16:10] <MattyMatt> I won my 25mm rail \o/
[14:18:59] <ChanServ> [#emc] "This is the #emc channel - talk related to the Enhanced Machine Controller and general machining. Website: http://www.linuxcnc.org/, wiki at http://wiki.linuxcnc.org/"
[14:19:04] <MattyMatt> if the slide fits the rail that's on, there'll be no downtime. I have to schedule my refits now I'm "in production"
[14:20:15] <ChanServ> [#emc] "This is the #emc channel - talk related to the Enhanced Machine Controller and general machining. Website: http://www.linuxcnc.org/, wiki at http://wiki.linuxcnc.org/"
[14:20:16] <MattyMatt> Hi awallin
[14:24:37] <elmo40> MattyMatt: won? from eBay?
[14:28:39] <elmo40> ok. I see that now. 2 for quadrature. and the indexing one for correct spindle position?
[14:28:56] <grommit> yes
[14:29:50] <MattyMatt> elmo, I don't prize fight for hardware anymore :)
[14:30:00] <MattyMatt> of course ebay
[14:30:18] <elmo40> I still get hung up on how it 'knows' where and when to start the thread. does it count the ppr, wait for the indexer, and thread from there? I guess I am trying to get too involved in the workings :P
[14:30:35] <elmo40> MattyMatt: why not? prixe fighting is a sport of all ages
[14:30:36] <skunkworks_> it waits for the index
[14:30:38] <MattyMatt> I nearly got sniped, so I paid nearly my top$
[14:31:00] <SWPadnos> elmo40, read about the software "encoder" component, and look at the sample configs that have spindle encoders set up
[14:32:00] <MattyMatt> 21gbp for a 72cm (2' 5") rail + slide in indeterminate condition
[14:33:47] <MattyMatt> I'll wreck my ballscrew if I keep going without one tho
[14:34:41] <MattyMatt> this oak ply is quite tough when you take big bites
[14:35:25] <elmo40> I bet
[14:35:34] <elmo40> that is cheap rail!
[14:35:47] <elmo40> I can only find 15" pieces for $40
[14:36:34] <MattyMatt> 3 + sliders at 11" went for 16gbp just before mine
[14:36:42] <elmo40> or this :/ http://qurl.org/nz0
[14:36:53] <MattyMatt> I didn't bid, because mine was after :) karma
[14:38:08] <elmo40> 1" rail, too?
[14:38:10] <elmo40> 25mm
[14:38:13] <MattyMatt> yep
[14:38:22] <MattyMatt> ah the 11" ones were 9mm
[14:38:29] <elmo40> damn. there is nothing here in n. america for that small of a price.
[14:38:35] <elmo40> http://shop.ebay.ca/i.html?LH_PrefLoc=3&_nkw=linear%20rail&_fln=1&_trksid=p3286.c0.m283
[14:38:37] <elmo40> take a look
[14:38:39] <MattyMatt> ebay.com?
[14:39:01] <MattyMatt> ah well if you're fussed about getting new ones :)
[14:39:16] <elmo40> lol. true
[14:39:21] <MattyMatt> I'm a second tier user
[14:40:13] <MattyMatt> somebody else can have the 1/10000th tolerance from it first
[14:40:19] <grommit> This link was posted yesterday (I think)...This company sells linear rails inexpesively. I don't know a thing about them...
[14:40:20] <grommit> http://cgi.ebay.ca/linear-bearing-rail-SBR16-350mm-2-rails-4-blocks_W0QQitemZ250584198605QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3a57fb6dcd
[14:41:34] <elmo40> but they are located in China... shipping would be expensive
[14:41:52] <MattyMatt> it says another $36 for US
[14:42:26] <elmo40> ya. plus duties. and the PITA paperwork.
[14:42:59] <elmo40> 'are you boys going to make bombs with this'... oh shut-up Feds.
[14:43:13] <grommit> I have purchased quite a few items from companies in China (not this particular one) and I have not had to pay any duties or do any paperwork.
[14:43:31] <MattyMatt> yeah the price they quote is all of it
[14:43:57] <grommit> just my experience, no endorsement for or against it. just sayin',,,,
[14:44:46] <MattyMatt> that was my 3rd choice after winning this one, and trying to get skateboard bearings running in the one I've got
[14:45:14] <grommit> BTW, speaking of encoders (we were weren't we?) :) This little device might come in handy for my situation: http://usdigital.com/products/aedr/
[14:47:03] <cradek> grommit: that's very interesting
[14:48:41] <MattyMatt> 3" diameter for 2048 ppr
[14:48:46] <MattyMatt> neat
[14:49:47] <MattyMatt> or linear on the ways, of course :)
[14:51:58] <elmo40> works like a CD? uses dark/light to trigger
[14:52:26] <elmo40> so, no holes in a plate required. just a marker on white paper :P
[14:52:58] <MattyMatt> 500ns rise time = 2Mhz sampling rate max
[14:53:20] <elmo40> nice
[14:53:24] <MattyMatt> so at 2048 ppr = 600000 RPM
[14:53:30] <elmo40> how fast can you send a signal to HAL?
[14:54:02] <elmo40> optical encoders are far more accurate then the magnetic ones. faster sampling, too
[14:54:51] <MattyMatt> would you use 2048 ppr or 2000 , with a 200 motor?
[14:55:22] <MattyMatt> do you want them in a harmonic relationship?
[14:56:21] <MattyMatt> ah somebody still has to make the codewheels and strips :)
[14:56:58] <MattyMatt> * MattyMatt paints stud balck, then files down shiny points
[14:59:17] <MattyMatt> with 2 you could make a vernier
[15:09:53] <MattyMatt> ah, count freq = 60khz. that limits it as a rotary
[15:10:12] <MattyMatt> not much tho
[15:10:26] <grommit> what is max at 60kHz?
[15:10:52] <MattyMatt> Count Frequency - - 60 kHz (rpm/60) x cycles/rev.
[15:11:26] <MattyMatt> that last bit is Notes, so is how to calc max rpm
[15:13:03] <MattyMatt> 2000 ppr would give you 1800RPM
[15:13:43] <MattyMatt> so you'd have to lower the res to use above that speed
[15:13:57] <grommit> cool, i want it for tapping. That is going to be lower then 1800rpm.
[15:15:45] <MattyMatt> it's not the "does everything" one I want for a spindle-thinks-its-an-axis
[15:16:38] <MattyMatt> not quite, and not by itself
[15:17:21] <MattyMatt> 1800RPM is plenty for a plywood chuck, anyway :)
[15:32:13] <JT-Work> yea my 16c collets showed up
[15:48:02] <elmo40> 16c? is that a size? ER16 equivilant?
[15:48:13] <elmo40> MattyMatt: did you forget something? the
[15:48:21] <elmo40> the 'k' in the frequency?
[15:48:36] <JT-Work> elmo40: yes, yes, no
[15:48:54] <elmo40> 60,000 Hz, not 60Hz
[15:49:29] <elmo40> it would be useful at higher then 1800 RPM ;)
[15:49:51] <elmo40> 1TB drives are $60 now
[15:50:07] <elmo40> makes building a RAID5 more feasible
[15:51:10] <JT-Work> elmo40: it is a bigger version of a 5c collet
[15:53:42] <elmo40> would assume so, being that 16 > 5
[15:53:44] <elmo40> lol
[15:54:39] <elmo40> ahh, so these things? http://qurl.org/oz0
[15:56:30] <JT-Work> yea
[15:59:33] <elmo40> they are for the quick release spindle?
[15:59:41] <elmo40> I don't know what to call it... spindle doesn't sound right to me
[15:59:51] <elmo40> chuck?
[16:00:13] <elmo40> but it is a collet :P
[16:02:05] <JT-Work> they fit inside of the spindle and I have a collet closer to draw them tight
[16:03:07] <JT-Work> the black part is sticking out of the collet in this vid http://www.youtube.com/watch?v=isTD6bDF_LI
[16:14:35] <frallzor> * frallzor got wood
[16:15:14] <frallzor> literally speaking http://pici.se/p/large/gguKYClVA/ :P
[16:17:58] <MattyMatt> elmo40, no I didn't forget the k, I assumed 2k ppr encoding
[16:18:34] <MattyMatt> like the expensive commercial absolute ones seem to have
[16:20:03] <MattyMatt> frallzor: what's it gonna be?
[16:20:12] <MattyMatt> rerap parts?
[16:20:23] <MattyMatt> it's still a seller's market :)
[16:20:40] <MattyMatt> just about, there's one guy printing faster than I'm milling
[16:21:22] <MattyMatt> so I may give up on the plywood end of the market soon
[16:24:06] <MattyMatt> milling pieces off the end of plank. this is the way to do it :)
[16:24:38] <MattyMatt> I need a flat vice with bigger jaws
[16:25:04] <elmo40> ahhh, 30,000RPM :) http://qurl.org/pz0
[16:25:26] <bill2or3> you should get together with someone who's printing. you can mill the easy-to-mill parts, and he can print the hard-to-mill parts, for maximum production rate.
[16:25:29] <MattyMatt> I might get 2 like I've got (same as the silverline crap) and cut them in half
[16:25:46] <MattyMatt> bill2or3: yeah, I should do the heavy parts
[16:26:16] <bill2or3> vertex's are a lot of printing-time, but they're super simple parts, and there's a lot of them.
[16:26:36] <MattyMatt> it would have to be nophead, or someone localish
[16:26:45] <MattyMatt> he's 35 miles from me
[16:27:11] <MattyMatt> he might not want to devalue his sets tho, he gets nice money for his
[16:28:02] <bill2or3> well, if he lowered teh price a little, but not so much that his profit-per-printing-hour decreases, then he'd actually be making *more* money.
[16:28:14] <MattyMatt> good point
[16:28:33] <MattyMatt> maybe I'll do part sets for the trade
[16:28:48] <MattyMatt> they'll need painting to match the plastic :)
[16:29:10] <bill2or3> nah, people can print their own replacements once their printer is running.
[16:29:37] <bill2or3> call it a "Quickstart parts set" or something like that.
[16:29:51] <MattyMatt> functional grade
[16:30:41] <bill2or3> then when someone has a working machine, and has printed their own replacements for the milled parts, they can re-sell them. (possibly along with the rest of a set, that they printed)
[16:31:43] <MattyMatt> I'd like to design a nice box with compartments, so you can use it to collect the replacements
[16:32:16] <MattyMatt> xmas morning empty it, and then by easter it's full again
[16:32:19] <bill2or3> that would also have the advantage of encouraging people to produce more parts sets.
[16:32:24] <MattyMatt> :)
[16:32:34] <elmo40> ok, $600 for that 30k RPM spindle. sounds good, doesn't it? http://www.tdmspindles.com/cat_01.asp Says 6Hp (4.5kW)
[16:33:35] <frallzor> MattyMatt reprap made out of 40mm oak? :P no way dude
[16:33:58] <MattyMatt> a few parts need 20mm
[16:34:02] <bill2or3> that's a lot of oak.
[16:34:14] <MattyMatt> * MattyMatt got an old wardrobe
[16:34:20] <bill2or3> I made my repstrap out of 1/2" oak.
[16:34:40] <frallzor> I got a nice supplier of hard wood now at least
[16:34:57] <frallzor> like 10x cheaper than any serious wood dealer =)
[16:35:03] <bill2or3> is it a tree?
[16:35:07] <elmo40> lol
[16:35:10] <elmo40> forest
[16:35:22] <MattyMatt> old wood is best
[16:35:25] <frallzor> its a man that has a forrest that makes wood =)
[16:35:38] <frallzor> and dries oak beech etc etc
[16:35:46] <MattyMatt> beech is good
[16:35:57] <frallzor> these are from an old oak he said
[16:36:14] <MattyMatt> no I mean old wood. well seasoned
[16:36:31] <MattyMatt> stopped warping 100 years ago
[16:39:42] <frallzor> I love the smell of machined oak
[16:40:29] <MattyMatt> this stuff is good for carving apparently http://en.wikipedia.org/wiki/Lime_tree
[16:40:36] <MattyMatt> and smells great
[16:40:57] <MattyMatt> momma has one out front, "Momma that branch looks dangerous"
[16:41:05] <frallzor> =P
[16:41:13] <frallzor> Wonder what to do with this wood...
[16:42:03] <MattyMatt> the next 3 chapters in your storybook for the blind about reindeers?
[16:42:34] <MattyMatt> that scene could be continued up & down too, as drawers
[16:43:17] <MattyMatt> wrap the scene around bowed drawer fronts, if the software will let you
[16:47:31] <elmo40> need a tach? http://qurl.org/qz0
[16:51:09] <frallzor> MattyMatt If I had 2 grand I could continue it :P
[16:59:59] <frallzor> but the guy getting me wood wanted a sign for his shop with the deer motif =)
[17:00:29] <Jymmm> frallzor: got pic of this deer?
[17:01:20] <Jymmm> frallzor: http://farm1.static.flickr.com/52/159018874_131de845ca.jpg
[17:01:55] <Jymmm> frallzor: I did that one, but nobody likes it it seems. lol
[17:03:00] <frallzor> http://www.pici.se/p/aBwpEvRwD/ this is the one I did
[17:03:00] <frallzor> :P
[17:03:07] <frallzor> or bought and did :P
[17:03:23] <Jymmm> Oh, the 3D one.
[17:04:09] <Jymmm> frallzor: what did you use for the cam?
[17:04:29] <frallzor> vectrics own machinist software for the files
[17:04:34] <frallzor> its super!
[17:04:56] <Jymmm> ah
[17:05:00] <frallzor> but only works with their files
[17:05:03] <frallzor> but it rocks
[17:05:10] <Jymmm> heh
[17:05:39] <frallzor> same stuff as in their good software they sell
[18:00:30] <MattyMatt> I am a 3d artiste in my other job. maybe I should knock up a few animal scenes
[18:01:47] <MattyMatt> surprise gcode
[18:02:02] <MattyMatt> damn axis will reveal it first
[18:03:02] <MattyMatt> can you use a chamfer mill with their software?
[18:03:28] <MattyMatt> that's the key to fine carving I think, especially with a reversable spindle
[18:04:13] <MattyMatt> I think these ones I got will work in both directions, they are a cone with a flat
[18:04:37] <MattyMatt> shame my spindle isn't reversible
[18:21:51] <MattyMatt> Jymmm: that looks like a woodblock for printing
[18:22:23] <MattyMatt> oooh wow. yeah. now there's a bit of software to write
[18:22:53] <elmo40> what are you writing?
[18:23:10] <MattyMatt> me? I'm just doing blender scripts
[18:23:46] <MattyMatt> blender is the one for me. full featured editor & renderer, all in C & python
[18:24:20] <MattyMatt> if I write CAM code in C, I'll put in blender, either a special branch or I'll pester the devs
[18:25:13] <MattyMatt> some things they'd accept straight away, like voxels and extra Z buffer utils
[18:26:01] <MattyMatt> physical materials I'd sell to the game engine people first, for more realistic physics :)
[18:27:05] <MattyMatt> "wouldn't it be great if the mass was automatically calculated?"
[18:27:42] <MattyMatt> "yeah, the springiness is the same as Young's modulus"
[18:30:30] <MattyMatt> "hardness affects the sound it makes when it hits something"
[18:31:29] <MattyMatt> yeah improving the physics sim will be popular everywhere
[18:35:08] <MattyMatt> python is a great language for hacking stuff together. I'm loving it
[18:35:25] <MattyMatt> except for the tabs
[18:47:09] <frallzor> my uncle isnt that clever despite his attempts of seeming clever :P
[18:47:48] <frallzor> my dad understands how the machine works, its very simple yet my uncle has trouble understandning simple stuff like how big it can mill :P
[18:47:49] <morficmobile> MattyMatt: counting { } is easier than tabs, to me
[19:03:48] <MattyMatt> both ways are easier with a smarter editor than I'm using :)
[19:04:33] <MattyMatt> although I think gedit does highlight matching {}
[19:58:16] <morficmobile> If i want to do stuff with spindle/servo load, which way would the drive have to be provide it, so it's easiest to use in EMC?
[20:07:29] <morficmobile> pjm: - torque / load feedback from variable frequency drive to EMC2 for load monitoring of spindle motor - partially done (Oct 2009)
[20:07:30] <morficmobile> <-- only thing i could find talking about it
[20:07:46] <morficmobile> oops, linebreak pasted too
[20:13:48] <SWPadnos> morficmobile, depends on the drive
[20:14:22] <SWPadnos> I think the GS2 driver already gives you the speed feedback, but I think the drive doesn't provide load information
[20:14:34] <JT-Work> on an absolute encoder with 10 bit gray code, 1024 pulses per revolution what is the smallest measurement in degrees you could get from it?
[20:15:04] <SWPadnos> if you have a drive that can communicate via modbus or some other serial protocol, you can do all the control with that (assuming that you can handle the uncertainty of userspace for speed changes)
[20:15:18] <SWPadnos> JT-Work, 360/1024
[20:15:50] <JT-Work> so it's not like a quad encoder then
[20:16:14] <SWPadnos> sure it is, but a 10-bit absolute encoder is like a 256-cycle quadrature encoder :)
[20:16:46] <JT-Work> ok, it's kinda greek to me
[20:27:14] <morficmobile> SWPadnos: thanks, the modbus/serial info is what i needed
[20:27:22] <SWPadnos> sure
[20:27:44] <SWPadnos> there are other ways too, of course
[20:28:02] <morficmobile> while i really just want to tell him "it has to have something", i figured it would be nice to make sure we get what works, not what could be worked around to *maybe* work
[20:28:07] <SWPadnos> (e.g. velocity output from encoder in counter mode acts like a frequency meter)
[20:28:39] <SWPadnos> well, modbus would need a little driver writing, but that should be relatively easy since there are a couple to start out with
[20:29:09] <SWPadnos> at the moment, we have no generic configurable modbus driver, so s different flavor is needed for each kind of device you want to attach
[20:29:15] <SWPadnos> s/s/a/
[20:33:06] <skunkworks_> I thought if you can deal with non-realtime - you could hook it through classic ladder..
[20:33:22] <SWPadnos> maybe
[20:33:24] <skunkworks_> through its modbus interface
[20:33:49] <skunkworks_> I don't know its capabillities
[20:33:52] <SWPadnos> I don't know that you can use the CL modbus driver with the HAL-ified version. it might be good to find out some day :)
[20:34:13] <pfred1> * pfred1 can leap over tall buildings in a single bound
[20:34:42] <skunkworks_> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?ClassicLadder_Ver_7.124
[20:41:19] <morficmobile> SWPadnos: any "needs a little driver writing" less ideas?
[20:41:28] <SWPadnos> hmmm
[20:42:50] <SWPadnos> I don't know that there's any way to get that data into EMC2 without a little bit of software, or by vastly limiting your hardware options
[20:43:20] <SWPadnos> I think the Motenc boards have analog input, and I believe Vigilant does as well (not sure about either)
[20:43:52] <SWPadnos> I don't know if the various analog input boards that Mesa makes have driver support at the moment
[20:44:25] <JT-Work> what kind of analog?
[20:44:30] <SWPadnos> phone
[20:45:55] <skunkworks_> JT-Work: you're using a voltage to frequency converter - then using an encoder channel to get the analog data into emc - right?
[20:46:11] <JT-Work> yes
[20:46:23] <JT-Work> the THC card from Mesa
[20:46:26] <morficmobile> a lot of people solder little chips together and write a little code, unfortunately it's an area i have no experience with, i hear driver, i think "tough, take a long time" :)
[20:46:30] <skunkworks_> so encoder velocity is proportional to voltage?
[20:46:42] <JT-Work> yes
[20:46:49] <JT-Work> plus an offset
[20:47:07] <skunkworks_> neat
[20:47:09] <JT-Work> 0-10v input or 0-300v input
[20:47:10] <pjm> yo
[20:47:24] <skunkworks_> pjm: how is the little machine?
[20:49:07] <Jymmm> THC Card?!?!?!?! OH YEAH BABY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[20:49:20] <seb_kuzminsky> not that kind of thc, Jymmm ;-)
[20:49:22] <SWPadnos> Jymmm, medicinal only
[20:49:37] <Jymmm> seb_kuzminsky: Oh wth =(
[20:49:40] <JT-Work> it always gets Jymmm excited when you talk about it
[20:49:48] <morficmobile> pjm: did you finish the torque/load feedback from VFD? would be very interesting to see how :)
[20:50:08] <Jymmm> SWPadnos: WORKS FOR ME, We gots Prop 215 here in Calif
[20:51:01] <pfred1> Jymmm the feds will be back with a vengance in 2012
[20:51:27] <pjm> morfic well i did some testing with it, my VFD has a metering output voltage that you can assign to various functions etc, one being load, so I built a V to F converter and measured it with an encoder input
[20:51:30] <Jymmm> pfred1: That's fine, I plan on being on a tropical island by then
[20:51:49] <pfred1> Jymmm its actually international law
[20:52:18] <SWPadnos> JT-Work, I was just thinking that the only way of getting torque or load information into EMC2 without writing a single line of code is if the VFD can output that data on an analog pin and EMC2 can read it
[20:52:36] <morficmobile> pjm: interesting, used one from the 7i33?
[20:52:43] <pfred1> Jymmm plus there's too many bugs in the tropics especially on islands
[20:53:02] <SWPadnos> any other option I can think of requires at least a *little* code
[20:53:10] <JT-Work> or hardware
[20:53:40] <SWPadnos> sure
[20:53:44] <SWPadnos> anything needs hardware
[20:53:45] <JT-Work> I've got a pokeys55 on the way it has 4 analog inputs and 1 analog output of the 55 I/O lines
[20:54:07] <SWPadnos> oh, I guess a frequency output could be used with either encoder or maybe mesa encoder (I think it has a counter mode, but I'm not sure)
[20:54:10] <pjm> morfic i am using the 7i37 for all my I/O
[20:55:03] <JT-Work> yea, I fed my freq into the 5i20 encoder and used the velocity from the encoder
[20:55:18] <pjm> i eventually plan to pid the spindle load with feed rate so as to keep constant cutting load etc
[21:20:57] <morficmobile> pjm: that's what we have in mind down the road
[21:21:29] <pjm> so i just need to jfdi, perhaps in the next couple of weeks i'll make a pid and test it
[21:23:02] <SWPadnos> morficmobile, there have been several discussions about monitoring servo load and reacting to that in some way (reducing feed rate, turning on extra cooling fans, sending emails ...)
[21:23:08] <morficmobile> SWPadnos: a little code is not bad, might be easier to find someone who has fun helping making it work
[21:23:30] <SWPadnos> you probably need realtime input for servo monitoring though
[21:23:36] <morficmobile> i'll have to search the archives
[21:23:48] <SWPadnos> well sure, if you send me a VFD I can modify the driver for you :)
[21:23:57] <morficmobile> :)
[21:24:00] <SWPadnos> I don't know that anyone has actually done it, I just know we've talked about it
[21:24:26] <SWPadnos> I did the GS2 driver at a CNC workshop a couple of years ago, it wasn't all that hard
[21:24:51] <morficmobile> an email after a crash is still possible even w/o RT maybe
[21:25:28] <SWPadnos> crash is a little late. servo or spindle load is something that you can monitor and (probably) react to before there's damage
[21:25:41] <morficmobile> big problem, the constant "don't know what happened" when the turret is off
[21:26:24] <morficmobile> reacting to it would be ideal, since there are more applications than just "foo crashed machine" emails :)
[21:26:41] <SWPadnos> sure
[21:27:35] <morficmobile> i guess i'll have to get in over my head and then learn a lot in the process of making it work
[21:27:58] <SWPadnos> the best thing to do is decide what you want the machine to do immediately and what you want it to do eventually
[21:28:34] <SWPadnos> pick hardware that lets you do as much of the immediate stuff as possible (which may be all of it), and which has the best path to the "eventually" stuff
[21:31:18] <morficmobile> when you said driver for GS2, you meant for the AD GS2's modbus?
[21:31:25] <SWPadnos> yes
[21:32:10] <morficmobile> you wouldnt have it to look at somewhere? to get me an idea
[21:32:28] <SWPadnos> it's included with emc2
[21:32:35] <SWPadnos> and it does output load percentage
[21:33:11] <SWPadnos> if you have the source, look at emc2/src/hal/user_comps/gs2_vfd.c
[21:34:03] <morficmobile> thanks, i did actually fetch it, to start poking at the interpreter
[21:34:22] <SWPadnos> eek. nothing like jumping in the deep end :)
[21:34:31] <morficmobile> you know i want my G71
[21:34:37] <SWPadnos> of course
[21:34:59] <morficmobile> i need to google some more math before i prot the interpreter though
[21:35:43] <morficmobile> day over! thanks, going home now! all you need is a bad back, and day flies by it seems
[21:35:50] <SWPadnos> heh. see you
[21:37:27] <PCW> YOu could get spindle load easily if your spindle drive is a servo running in torque mode (PID output = torque perhaps with a little low pass filtering)
[21:38:00] <SWPadnos> true
[21:38:15] <SWPadnos> same for axis servos actually
[21:39:47] <PCW> Probably easier on spindle as torque mode is likely to require >1 KHz servo rate for axis
[21:40:27] <pfred1> just when you thought you knew everything there was to being a cad they invent these computers
[22:08:17] <Spida_> what kind of steppers / stepperdrivers / interfaceboard should I use (or at least consider) for a diy mill with an workable area of 60cm*30cm*12cm that should at least be able to work with aluminium?
[22:09:01] <andypugh> Nema 23 is about the minimum stepper size, probably.
[22:09:28] <andypugh> Leadscrews or ballscrews?
[22:13:49] <pfred1> what sort of linear ways is the minimum for working aluminum I wonder?
[22:14:26] <pfred1> I mean i know working aluminum is pretty cheesy stuff but I don't think any gantry style machines are still actually up for the task
[22:19:00] <archivist> depends how stiff you can make the machine
[22:32:14] <morfic> PCW: thanks
[22:32:21] <andypugh> I have seen gantry-style jig-borers. Plenty stiff enough.
[22:34:37] <PCW> welcome morfic
[22:36:17] <andypugh> This is probably quite big, isn't it?
[22:36:18] <andypugh> http://cgi.ebay.co.uk/Bridgeport-Series-1-CNC-Milling-Machine-PC-controlled-/300429328894
[22:36:33] <Valen> wont fit in your pocket
[22:37:37] <andypugh> They have huge steppers, I think?
[22:37:59] <Valen> dunno, i think danimals did
[22:38:24] <JT-Hardinge> that's an OEM cnc bp 1 not a retrofit like mine
[22:39:25] <L84Supper> any news on the new Live CD? Any help needed getting the ISO together?
[22:40:24] <Valen> I'm happy to test
[22:43:01] <seb_kuzminsky> i think they're still working on issues getting the lucid kernel to work well with rtai
[22:43:37] <L84Supper> yeah, Canonical picked a bad kernel this time
[22:44:23] <L84Supper> backports just days before launch
[22:45:47] <Valen> L84Supper what happened?
[22:46:04] <PCW> Hi Sebastian!
[22:46:16] <seb_kuzminsky> hi PCW, long time no see :-)
[22:46:28] <seb_kuzminsky> are you coming to the cnc workshop?
[22:47:25] <L84Supper> canonical picked a kernel with lvds quirks in KMS and some other issues, they were warned
[22:47:52] <L84Supper> ATI had to tweak drivers at the last minute as well
[22:48:18] <PCW> Ya been pretty busy here
[22:48:35] <PCW> I'd like to
[22:49:04] <seb_kuzminsky> cool!
[22:49:27] <andypugh> Out of curiosity, when, where, and what is this CNC workshop of which you speak?
[22:49:34] <PCW> Dont think I can be of much use but would be nice to see some of the EMC characters in person
[22:49:54] <seb_kuzminsky> andypugh: it's in Ann Arbor, Michigan, June 22-25
[22:50:02] <seb_kuzminsky> http://bbs.homeshopmachinist.net/showthread.php?t=36635
[22:51:11] <andypugh> I need to persuade work that it is critical I visit head-office in Dearborn. :-)
[22:57:10] <L84Supper> is it BYO CNC or?
[22:59:10] <MattyMatt> andypugh: I got the 1" rail from that place in Croydon :)
[22:59:23] <andypugh> Great
[22:59:25] <MattyMatt> thanks for the tip
[22:59:39] <MattyMatt> 68gbp the set of 8 went for
[22:59:59] <andypugh> I don't know where their stuff comes from. Seems odd stock for a charity shop
[23:00:41] <MattyMatt> the sets of 3 went cheap, but I got the feeling it was bad karma to bid on those just before the one I really wanted
[23:02:25] <MattyMatt> best to let as many people walk away happy first :)
[23:03:26] <MattyMatt> now hopefully the slide will go straight on the rail I have already
[23:04:06] <andypugh> Sounds a little optimistic.
[23:04:22] <MattyMatt> they're both 1" or 25mm
[23:04:34] <MattyMatt> how many brands? 3 or 4?
[23:05:07] <andypugh> I don't honestly know.
[23:05:20] <MattyMatt> and in the UK, probably fewer, these are both out of UK factories
[23:05:30] <pfred1> isn't 1" 25.4 mm?
[23:06:05] <MattyMatt> yeah, but I don't, and the Croydon people probably don't, know where to measure them from
[23:06:39] <andypugh> You got the long 25mm not the short 9mm ones?
[23:06:39] <MattyMatt> the grooves are deeper than 0.4mm
[23:06:47] <pfred1> I boxed up all my motor drivers today they're all done
[23:06:50] <MattyMatt> yeah I got the long one
[23:07:14] <pfred1> all 5 of them!
[23:07:51] <MattyMatt> pfred1, this place had 5 phase steppers. 4 for ~$50
[23:07:59] <pfred1> * pfred1 is now the proud owner of 5 assembled and tested stepper motor drivers and a break out board too
[23:08:00] <MattyMatt> only 2 were 5 phase
[23:08:16] <pfred1> MattyMatt all of mine are 2 phase
[23:08:41] <MattyMatt> so far :)
[23:09:03] <Spida_> andypugh: ballscrews probably
[23:09:04] <MattyMatt> 5p is worth the effort, from what I've heard
[23:09:07] <Spida_> Spida_ is now known as Spida
[23:09:28] <pfred1> probably less deadbanding
[23:09:57] <pfred1> steppers really do suck but hey its as simple as it gets
[23:09:58] <MattyMatt> and each phase only switches every 2.5 steps
[23:11:00] <pfred1> if i ever do my mill I'll try servos on it
[23:11:02] <MattyMatt> 2 on, 3 off, I think
[23:11:23] <andypugh> Spida: I have 4A Nema 23 steppers on a machine about the size you are describing, and it is OK. If I was doing it again I would use 16mm or perhaps 12mm balscrews, the 20mm is just a bit big (very rigid, but the balls are further out, so for the same thrust force, it takes more torque to turn it)
[23:12:27] <pfred1> I'm running dual 2 amp steppers on the X and Y axis
[23:12:51] <pfred1> dual duals
[23:13:29] <Spida> andypugh: what kind of stepper drivers?
[23:13:36] <MattyMatt> could you have them geared to spread the power band?
[23:13:51] <andypugh> Mine was taking 10mm depth of cut with a 12mm endmill in Aluminium this evening (making a new Z-motor mount of ritself). It was noisy, but that is the head, not the steppers.
[23:13:56] <MattyMatt> e.g. 4 steps of one to 1 of the other?
[23:14:34] <pfred1> MattyMatt I'm already running 16,000 steps to the inch on one axis
[23:14:40] <andypugh> I am using Motion Control Products ones, which I think are similar to Xylotex.
[23:14:55] <andypugh> Spida: Where are you?
[23:15:03] <Spida> germany
[23:15:16] <MattyMatt> geared up, so have 16k and 4k, with power reduced to the 4k stepper at low speed
[23:15:23] <pfred1> Spida get geckos and run mach
[23:15:40] <Spida> mach is windows, isn't it?
[23:15:56] <andypugh> You will have the same issue as me then, everyone says that Geckos are good, but I didn't fancy the transatlantic hassles if it went wrong.
[23:16:15] <Spida> no way that I will run windows if I can avoid it
[23:16:17] <andypugh> (And I think pfred1 was joking, channeling the spirit of CNCZone)
[23:16:23] <pfred1> heh
[23:16:46] <pfred1> it does seem to be the obvious solution for your run of the mill rubes
[23:16:48] <Spida> I have been 100% windowsfree for 3,5years.
[23:16:58] <andypugh> I don't think that there is anything wrong with Gecko drives.
[23:17:08] <MattyMatt> get chinese 4axis TB6560 driver
[23:17:10] <pfred1> andypugh they're too expensive
[23:17:17] <andypugh> Apart from that
[23:17:23] <pfred1> but they are really nice i suppose
[23:17:54] <pfred1> nicer than my drivers I'll admit it but i can have 20 of my drivers for the price of one of theirs
[23:18:07] <pfred1> and they're not THAT much nicer
[23:18:14] <andypugh> Yeah, to be honest starting with a really cheap chinese drive isn't a bad plan. It's what I did in the first place. See it as a €50 starter kit while you work out what you really want.
[23:18:42] <pfred1> yeah the TB6560 boards are nice if you're not a complete moron with them
[23:18:46] <MattyMatt> I don't see a reason to upgrade, until it fails
[23:19:14] <MattyMatt> (until I blow it)
[23:19:40] <pfred1> Spida http://www.youtube.com/watch?v=cgbeyNNBZ68
[23:19:55] <andypugh> (What you really want is 500W servos, but it takes a while to realise that. Then you buy the 4 tonne machine, build an extension to the house.....)
[23:20:25] <pfred1> andypugh I'm up to 93 views
[23:20:40] <MattyMatt> no house
[23:21:14] <pfred1> MattyMatt long as you stick below 24 V I don't see why you would
[23:21:14] <andypugh> Spida: http://shop.ebay.de/?_from=R40&_trksid=m570&_nkw=TB6560
[23:21:23] <andypugh> Will get you going nicely.
[23:21:43] <MattyMatt> below 24? I was planning to go to 24
[23:21:48] <pfred1> even if they can't speel board
[23:22:00] <Spida> *g*
[23:22:17] <Spida> what about the mesa stuff?
[23:22:17] <pfred1> Spida same IC i made my last stepper drivers out of its not bad
[23:22:25] <Spida> too expensive?
[23:22:27] <pfred1> mesa is for servos
[23:22:42] <pfred1> its the break out board
[23:22:59] <pfred1> or your I/O
[23:23:34] <pfred1> so you need amps besides
[23:23:36] <MattyMatt> I run that board on one printer port, with the cable they supply
[23:23:56] <pfred1> least thats what it seems like to me
[23:24:02] <Spida> hm, no printer ports left here...
[23:24:06] <andypugh> No, I predict you will probably end up with a Mesa (or Pico, or some other) card eventually, if only to get more IO. But until you start using the machine you won't know what you need. Yo could easily spend $500 on Mesa cards and then find you got the wrong setup.
[23:24:09] <Spida> all legacy-free :-/
[23:24:14] <pfred1> Spida PCI slot?
[23:24:27] <Spida> ok, thats an idea *g*
[23:24:34] <pfred1> Spida its how i run mine
[23:24:46] <pfred1> with a dual P-port PCI card
[23:24:47] <andypugh> Spida: No parallel port? In that case you _do_ need a Mesa (or similar) card.
[23:25:01] <andypugh> Or a PCI P-port card.
[23:25:01] <pfred1> cost me a whopping $15
[23:25:29] <pfred1> Spida we all seems to like the Rosewill cards here
[23:26:14] <andypugh> I like the Mesa 7i43 which connects to the P-Port and gives you 48 IO pins with hardware stepgens and encoder counters, but it seems daft to install a PCI card to connect one up when there are PCI versions of the cards.
[23:26:45] <Valen> to my mind the PCI version should have lower latency
[23:26:51] <Valen> just a gut feeling
[23:26:58] <Spida> I just don't know how long pci will be around (before it is replaced with pcie)
[23:27:15] <MattyMatt> almost certainly if you're trying to toggle 48 bits through 8
[23:27:27] <pfred1> Spida old computers don't evaporate
[23:27:46] <Valen> it'll be around long enough that by the time you have difficulty finding one, you will be wanting something other than your existing mesa card anyway
[23:27:46] <Spida> no, but they blow out their megic smoke
[23:27:51] <Spida> magic...
[23:27:58] <Valen> I have a 386 that is still running
[23:28:00] <MattyMatt> you can get pcie dual-port cards too. more expensive than pci tho
[23:28:03] <andypugh> Well, if you want to future-proof yourself there is the Mesa 3x20 which is wired-PCIE and has 144 IO pins. But costs money
[23:28:05] <Spida> alectrolytoic caps tend to blow up one day or another
[23:28:13] <pfred1> MattyMatt 8 bits translates into 255 unique states
[23:28:26] <MattyMatt> Valen, mine has a Weitek copro
[23:28:45] <pfred1> MattyMatt but yeah p-port max bandwidth is way lower than pci
[23:28:50] <MattyMatt> and MCA bus :)
[23:29:00] <Valen> but thats the thing, if you get a PC and a mesa card togther odds are being similar equipment they will probably EOL at the same time
[23:29:03] <Valen> (end of life)
[23:29:19] <pfred1> fastest p-port goes is like 2.5 mbits/s I think
[23:29:20] <andypugh> But EMC isn't very demanding of CPU, (or of IO bandwidth). All it needs is things to be _predictable)
[23:29:53] <pfred1> andypugh on my old junker it because a factor if i wanted to use highest microstepping rate
[23:30:17] <pfred1> andypugh which I did but my machine could only stream to .8 ip/m
[23:31:29] <andypugh> Yes, software step generation can become limiting, but telling a 7i43 to step at 20kHz for the next mS is a far different proposition to trying to send the actual steps down the P-Port
[23:32:10] <pfred1> I think i was running closer to 50 KHz
[23:32:45] <andypugh> I don't know what the limit is of the Mesa stepgens. Quite possibly MHz.
[23:32:55] <pfred1> there's still a lot of questions as to exactly what is going on with all of that
[23:33:28] <pfred1> coz if I set the microstepping higher I could get faster gens it was weird
[23:33:56] <pfred1> I honestly don't know why things topped out like they did and do yet
[23:34:06] <andypugh> I still think Spida should start with an eBay card and a P-port system and actually get a machine moving before spending serious money on hardware.
[23:34:19] <pfred1> heck yeah
[23:34:22] <MattyMatt> hear hear
[23:34:27] <pfred1> it may do the trick for them
[23:34:43] <MattyMatt> copy MattyMatt, it worked for him (so far )
[23:34:52] <Spida> I still can't decide on the design... do I want a moving table? that would probably be more exact, since only two axis's tolerances add up, but also the size of the machine would increase considerably...
[23:35:03] <pfred1> Spida if yo uwant to blow serious cash get nice ballscrews
[23:35:25] <pfred1> Spida if you do you can get away with a lot less motor and driver
[23:35:36] <MattyMatt> Spida, you have reached the correct dilemma
[23:35:42] <Spida> ok
[23:35:53] <Spida> at least I have understood the problem correctly
[23:35:57] <pfred1> Spida or at a later date you can always put better on it and get better out of it too
[23:35:57] <MattyMatt> space vs accuracy & simplicity of alignment. your call
[23:36:25] <pfred1> Spida but with the right lead screw yo ucan get mind blowing performance
[23:36:25] <Valen> Spida take a look at linearmotionbearings2008 on ebay for ballscrews and possibly slides
[23:36:38] <Valen> new and cheap and "good enough"
[23:36:53] <MattyMatt> what are your walls made of? I like the concpt of overhead gantries
[23:37:09] <pfred1> MattyMatt hey thats my idea
[23:37:11] <MattyMatt> is it a mill? or is it a crane?
[23:37:24] <pfred1> MattyMatt well I'm going overhead leadscrews
[23:37:55] <pfred1> really everything is going to be overhead
[23:38:07] <Spida> what kind of accuracy can I get out of a fixed table (thats gantry style, isn't it?)?
[23:38:23] <MattyMatt> most people never use the top half of the room
[23:38:23] <andypugh> Though backlash is more important in ballscrews than linear accuracy. You really don't care that two holes 500mm apart might be 500.01 apart. Two slots 5mm apart that are really 5.0001 is fine.
[23:38:24] <pfred1> Spida yes
[23:38:36] <MattyMatt> landlords only charge for the floor
[23:39:07] <Valen> accuracy isn't down to the style of machine, all of them can be made to be arbitrarily accurate
[23:39:52] <pfred1> I think its easier to make a moving table more accurate than a moving gantry
[23:40:13] <Spida> http://www.youtube.com/watch?v=meZBUQbGDqA <- that looks interesting
[23:40:13] <Valen> thats probably a fair statement
[23:40:20] <Valen> downside is room used
[23:40:26] <pfred1> indeed
[23:40:39] <Spida> I am just not sure if I want the table free hanging....
[23:41:00] <Valen> makes life easier in my respects
[23:41:16] <Valen> you can put one ballscrew in the middle to drive it all around
[23:41:26] <pfred1> Spida I like this design http://www.mechmate.com/
[23:41:55] <pfred1> well i should say lots of elements of it
[23:42:36] <andypugh> Spida: What do you intend to make with it?
[23:42:46] <pfred1> there's a few people in here with mechmate based machines as well
[23:42:47] <MattyMatt> yeah size is a big factor in the moving table choice. a vertical mill would generally always be moving table
[23:43:38] <andypugh> There have been a few Elgamills on eBay recently.
[23:43:54] <andypugh> But they take up a lot of space :-)
[23:44:18] <Spida> milling composites (like FR4, with and without copper), aluminium, perhaps (styro)foam, ....
[23:44:28] <Spida> mostly electronics and rc-related stuff
[23:44:33] <pfred1> thats all over the board
[23:45:38] <pfred1> your best bet is make a dedicated PCB mill to get the hang of things then make a machine for the bigger stuff with what you learned
[23:46:08] <MattyMatt> copy the Sable 2015
[23:46:11] <pfred1> like make a PCB mill as cheaply as you can and just do do PCBs and you'll know exactly how to make your other machine
[23:46:36] <MattyMatt> or buy one, $500 is very reasonable IMO
[23:46:43] <Spida> hm, my idea was to do it the otherway around...
[23:46:50] <pfred1> pfft you can make one far cheaper
[23:47:05] <Spida> I have access to a LPKF protomat S62 at university.
[23:47:08] <MattyMatt> yeah, a wooden copy :)
[23:47:22] <MattyMatt> ah cool. mill a sable 2015
[23:47:31] <MattyMatt> in solid alu
[23:47:39] <andypugh> Depends on what you think your time is worth. Mine is free because this is a hobby, but if the CNC keeps you away from the _real_ hobby...
[23:48:10] <pfred1> yeah if you're rolling in dough and can't be bothered by all means buy something there are great products out there
[23:48:23] <Spida> oh, thats how I got on computerscience. cataloging a collection of other stuff.
[23:48:23] <MattyMatt> that reminds me. http://hackaday.com/2010/03/10/jeri-makes-integrated-circuits/
[23:48:36] <Spida> now I am at university studying cs...
[23:48:43] <pfred1> you can get really nice PCB mills for around $7,500
[23:49:10] <pfred1> well Ok so so ones
[23:49:40] <pfred1> but they're really nice compared to what most people can make
[23:50:56] <MattyMatt> I reckon mine will mill 0.1" tech with this new rail
[23:51:37] <andypugh> I think I have fallen in love. Outgeeked by a girl!
[23:52:33] <Valen> Spida, I wouldn't bother with a PCB mill
[23:52:34] <MattyMatt> she tells you about the ion mill she's making from a broken electron microscope
[23:53:01] <Valen> toner transfer works fine for making PCB's
[23:53:14] <MattyMatt> and how she sawed a CRT in half trying to make her first electron microscope
[23:53:20] <Spida> Valen: but still the problem of doing vias remains
[23:53:21] <Valen> then strap a dremel to your steel cutting mill to drill the holes
[23:53:52] <Valen> you cant do plated through holes with any non "pro" method anyway so no big loss there
[23:54:11] <pfred1> Spida they make inserts for that
[23:54:39] <Spida> my last pcb had 330 vias that had to have both sides connected. a few (50 or so) were buried below SMDs...
[23:54:50] <pfred1> toner transfer ruined 2 laster cartriges here for me
[23:54:59] <Spida> so, no way I am going to do that by hand.
[23:55:04] <Valen> Spida batchpcb is your friend
[23:55:17] <Spida> not if I can get a single pcb made for 15¤
[23:55:36] <Spida> Valen: or any other pcb-service, yes.
[23:55:50] <Valen> pfred1 thats because you used some magic paper crap, normal toner transfer uses plain white paper or can do anyway
[23:56:13] <Spida> but I am milling a lot of fr4 (without copper) lately, its cool for building stuff...
[23:56:49] <Valen> you should learn to fiberglass lol same material but additive rather than subtractive creation
[23:57:24] <pfred1> Valen yeah i remember teaching one kid how to fiberglass then his brother talked to me and was like man ever since then he's been fiberglassing the world!
[23:57:42] <Valen> its good stuff
[23:57:54] <MattyMatt> do both. make it blobby additively, then put a crisp finish on in the mill
[23:57:54] <Valen> my father worked in fiberglass for ~20 years
[23:58:07] <pfred1> you can make a car a boat or a plane out of the stuff so it must be
[23:58:10] <Valen> heh crisp finish on milled fiberglass
[23:58:43] <andypugh> I am thinking of having some PCBs made for my servo drives, if I ever get a working design. ten of 10cm x 10cm double-sided for $40? Not worth messing about.
[23:58:58] <pfred1> now this is what i call getting into your work: http://www.windpowerengineering.com/wp-content/uploads/2009/11/eew-machenbau-jpg.JPG
[23:59:27] <Valen> thats not a mill, this is a mill rofl
[23:59:39] <MattyMatt> :) that's the ticket
[23:59:41] <andypugh> Is it a mill or a probe?
[23:59:53] <Valen> bags not me with the chopper gun glassing that up