#linuxcnc | Logs for 2013-07-22

[01:12:52] <WalterN> hmm
[01:13:04] <WalterN> is Nickel Acetate required for the sealing process of anodizing?
[01:15:29] <WalterN> oh, no...
[01:15:36] <WalterN> not really anyway
[01:29:38] <WalterN> its for color leaching for the sealing process
[01:29:47] <WalterN> evidently
[02:08:34] <DJ9DJ> moin
[06:31:43] <Loetmichel> mornin'
[07:19:33] * Loetmichel had just bought a new motorcycle helmet. with sun visor integrated... feeling a bit like F14 pilot ;-) -> http://www.cyrom.org/palbum/main.php?g2_itemId=14355
[07:19:48] <Loetmichel> ... just missing a dual google glass and 2 flir cams ;-)
[07:50:10] <jthornton> I need one like that for rain
[08:23:15] <cradek> Loetmichel: I have one like that too, and I feel like if I ever got bumped, the sunglass part would take my nose off, yuck
[08:26:47] <Loetmichel> thats plastc
[08:26:56] <Loetmichel> +i
[08:27:07] <Loetmichel> and will break off
[08:27:59] <Loetmichel> besides: thanks to a school braw my nose will give way ;-) -> http://www.cyrom.org/palbum/main.php?g2_itemId=5519
[08:54:06] <MrHindsight> http://www.sciencedirect.com/science/article/pii/S1352231013005086 just when you thought it was safe to use a glue gun
[10:18:22] <CaptHindsight> http://www.koolrite.com/bioarmor.html has anyone tried these?
[11:02:58] <skunkworks> https://www.youtube.com/watch?v=nCg6blAACBI
[11:09:46] <Connor> skunkworks: Cool.
[11:09:48] <andypugh> A rivett 608 lathe cost $1600 in 1942. Perhaps that is how the company could be profitable despite my 1939 version being only serial number 393 of a type that was first made in 1922,
[11:16:41] <jdh> did they make 10s of other models that sold thousands?
[12:20:06] <Loetmichel> re @ home
[12:37:41] <skunkworks> Go figure - the back of the manual for the enco compact 5 lathe software has the pinouts of the printer port and a theory of operation of steppers
[12:38:04] <skunkworks> showing half step/full step and such
[12:42:52] <skunkworks> http://imagebin.org/index.php?mode=image&id=265261
[12:43:55] <Loetmichel> skunkworks: the emco compact 5 cnc lathe is a teaching machine. so that makes perfect sense ;-)
[12:44:07] <skunkworks> sure!
[12:44:58] <skunkworks> they frame it in such a way that it seems like they want you to make your own control software..
[12:46:52] <skunkworks> But they talk about the strobe bit and how some computers automatically sent out the strobe - but on other comptuers the 'programmer' may have to supply the signal ;)
[12:47:10] <Loetmichel> hrhr
[12:47:17] <Loetmichel> thats a bit older
[12:47:33] <Loetmichel> i think the compact5 cnc was designed in the 80ties
[12:47:38] <Loetmichel> late 80ties
[12:47:51] <Loetmichel> at that time the Dos PCs had 12 Mhz ;-)
[12:47:52] <skunkworks> yes - well - I don't know when they started making the PC version..
[12:48:04] <skunkworks> (computer controlled lathe)
[12:49:35] <TekniQue> nice
[12:51:41] <archivist> In the UK the BBC computer would be used for education cnc at the time
[12:52:53] <ReadError_> yea the UK is blocking all the porn now too
[12:54:11] <archivist> load of hype
[13:11:14] <IchGuckLive> hi all B)
[13:11:35] <IchGuckLive> to hot here in germany to sit on the PC went for a swimm after work
[13:15:43] <IchGuckLive> someone on libreoffice on windows XP
[13:24:33] <IchGuckLive> B)
[13:35:39] <JT-Shop> skunkworks: your just now finding that?
[13:36:10] <skunkworks> JT-Shop, yes... oh well
[13:36:31] <JT-Shop> at least you have some conformation about your research
[13:36:40] <skunkworks> yes :)
[13:48:22] <fbx90> hola
[13:49:18] <fbx90> what's the cheapest way to replace a low torque stepper with a low torque servo on a desktop machine
[13:49:40] <fbx90> i've been looking at $15 ebay servos but i'm not sure which controller and amplifier to use
[13:50:37] <archivist> "$15 ebay servos" er I hope you dont mean modellers aircraft type servos
[13:50:43] <fbx90> no
[13:50:47] <fbx90> not at all
[13:51:06] <fbx90> more like this:
[13:51:08] <fbx90> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=161065160725&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en#shId
[13:51:36] <fbx90> so that's more like $25....
[13:52:27] <archivist> http://emergent.unpythonic.net/projects/01142347802
[13:56:39] <fbx90> that's interesting, but i'd probably also need an amplifier?
[13:57:23] <pcw_home> He used a LM298 Hbridge
[13:57:37] <pcw_home> (Thats a amplifier of sorts)
[13:57:38] <archivist> that needs encoder feedback not tacho as your ebay item
[13:57:57] <fbx90> pcw_home: he had really small servos though
[13:58:03] <fbx90> not sure if i could get away with that
[14:00:55] <pcw_home> LM298 is 46V 4A max so for pretty small motors
[14:01:26] <pcw_home> but there are bigger Hbridges or you can make your own
[14:03:19] <fbx90> that might work, but i'd rather have some more overhead
[14:03:45] <fbx90> so yeah, h bridges
[14:10:20] <fbx90> as far as new motors, probably looking at something like this
[14:10:22] <fbx90> http://www.homeshopcnc.com/index.php?page=shop.product_details&flypage=gk_flypage.tpl&product_id=26&category_id=4&option=com_virtuemart&Itemid=1
[14:12:18] <archivist> with proper servos some mesa cards then :)
[14:13:03] <fbx90> i'm going to have a 5i25 for my steppers in a few days. some other folks here recommended some mesa daughter cards... but i've been having a hard time telling the difference between them
[14:13:31] <fbx90> and whether i need pwm output or +/-10V output
[14:13:50] <fbx90> and which mesa cards have which
[14:16:47] <andypugh> fbx90: For the 5i25 you can use a 7i76 for steppers or 7i77 for servos.
[14:19:34] <fbx90> andypugh: it seems like the 7i77 supplies +/-10V output...
[14:19:46] <andypugh> Yeah, that's for servo drives.
[14:20:16] <fbx90> something that's been confusing me is whether all the servo drives i find which are labeled as PWM servo drives, accept PWM input, or are simply PWM'ing their output...
[14:20:41] <fbx90> like all the AMC servo drives
[14:21:26] <andypugh> They all PWM their output, but some also want a PWM input.
[14:23:50] <fbx90> if i could get away with a much smaller servo, would i be able to dangle a 3c20 off the 5i25 and connect it directly to the servo?
[14:26:16] <andypugh> I am fairly sure that the 3C20 doesn't work with LinuxCNC, but you ought to ask PCW. For the DC servos you listed I think you would be looking at the 7i29
[14:28:09] <andypugh> But, (and this is important) the 7i29 is intended for the other type of Mesa FPGA card, with the 50-pin header rather than the D-plug.
[14:28:36] <fbx90> what's the operative difference between the 7i29 and 7i77 which makes it more suitable for the motors i listed?
[14:29:02] <andypugh> The 7i29 is a drive, the 7i77 is a daughter card.
[14:29:52] <fbx90> oh i see
[14:33:20] <andypugh> If you already have the 5i25 coming, then I suggest seeing how you get on with steppers.
[14:33:46] <andypugh> Maybe keeping an eye out for cheap +/-10V controlled drives.
[14:36:45] <fbx90> yeah, i need the 5i25 anyway because i'll still have 2 axes with steppers
[14:37:04] <fbx90> and maybe when the 5i25 gets here, and i can run with smaller microsteps, i'll be able to do without a servo on the axis in question
[14:37:10] <fbx90> good call there
[14:38:46] <fbx90> this is for a piece of weird optical machinery we developed in-house
[14:39:05] <fbx90> and that axis needs to be extra smooth
[14:40:19] <t12> andypugh: I read you've worked with an 8i20 + ac servomotor?
[14:40:38] <andypugh> Yes, my milling machine runs 8i20s.
[14:40:49] <t12> what kind of angular resolution can you get out of it?
[14:41:09] <andypugh> I am not sure.
[14:41:27] <t12> i've been thinking of setting one up for direct drive lathe spindle
[14:41:54] <andypugh> Given that the resolver interface has 24 bits of resolution, it ought to be possible to get pretty spectacular resolution.
[14:42:29] <fbx90> hmm, that's something i'm dealing with on another of our weird-ass machines...
[14:43:02] <fbx90> trying to get <.04 degrees on one axis
[14:43:31] <andypugh> Should be possible with a multi-pole resolver, I think.
[14:44:09] <andypugh> I was going to experiment with an 8i20 and a washing machine motor, but I accidentally bought a Rivett 608 and that moved the washing machine motor down the list.
[14:44:57] <t12> for high accuracy are resolves superior to optical encoders?
[14:44:57] <fbx90> heh
[14:44:58] <t12> resolvers
[14:45:23] <andypugh> t12: Yes.
[14:45:32] <andypugh> Washing-machine motor: http://www.youtube.com/watch?v=_P027KQ8ZHo&feature=share&list=UUexvgsGz_QFvOublovDYoTQ
[14:46:32] <fbx90> the inside of that is pretty cool looking
[14:47:38] <andypugh> t12: because Resolvers are analogue devices you can get much better accuracy.
[14:48:25] <t12> i see these mitsubishi servos that say they have 2^17 count encoders?
[14:48:54] <fbx90> jesus
[14:49:03] <t12> or maybe i'm misinterperting
[14:49:27] <fbx90> i'm looking at 2500count optical encoders which can give me 10k counts in quadrature
[14:49:43] <t12> let me see if i can find a datasheet
[14:50:34] <fbx90> i've seen 5k and 10k, which translate to 20k and 40k respectively, but everything higher that i've seen hasn't been in an actual product
[14:51:07] <t12> http://www.mrostop.com/pdfs/mr-j3.pdf
[14:51:15] <t12> mr-j3
[14:52:06] <andypugh> t12: The Mesa resolver card gives 2^24 bits of resolution (probably 16 bits of accuracy, in real terms).
[14:52:39] <andypugh> But you can also get high pole-count resolvers, so can multiply the two numbers together.
[14:53:05] <t12> then its sort of like
[14:53:12] <t12> however many a/d bits per pole section
[14:53:20] <t12> and the resets to zero, and you just track poles?
[14:53:44] <andypugh> Yeah, sort-of :-)
[14:53:51] <fbx90> yeah, if i understand what you're saying :)
[14:54:07] <CaptHindsight> nice, when did washing machines start using brushless motors?
[14:54:23] <fbx90> when did they stop using hand cranks? :D
[14:54:45] <fbx90> you guys and your futuristic washing machines
[14:54:46] <CaptHindsight> hand crank and hand operated bush
[14:54:47] <andypugh> CaptHindsight: I think it's been about 5 years, maybe more.
[14:54:49] <archivist> do they still use a rock in the river!
[14:54:51] <CaptHindsight> brush
[14:55:14] <fbx90> heh
[14:55:44] <CaptHindsight> the transmissions were usually what would wear out along with the relays
[14:56:15] <fbx90> http://www.ebay.com/itm/KOLLMORGEN-AKM41H-BKCNR-00-SERVOMOTOR-NEW-OLD-STOCK-/290945281457?pt=LH_DefaultDomain_0&hash=item43bdb0adb1
[14:56:34] <CaptHindsight> they must have figured out how to make a motor for less and how to undersize it just right to last the warranty + few months
[14:57:10] <jdh> my washer uses a plain old almost-framed induction motor
[15:00:19] <t12> maybe i can make my description more vague!
[15:00:27] <t12> heh
[15:04:52] <andypugh> fbx90: A nice motor, but only one of it.
[15:05:30] <CaptHindsight> I've been using Parker servo drives for while now. Usually ~$100 on ebay unless they have some factory bus everyone wants, then they sell for 4X or more
[15:05:41] <andypugh> I have been watching this set, but have avoided buying it. http://www.ebay.com/itm/261144227546?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649
[15:06:09] <fbx90> andypugh: yeah, luckily i only need one :)
[15:06:51] <fbx90> andypugh: what application do you have in mind for those?
[15:07:19] <andypugh> I was looking at a lathe conversion (X, Z and toolchanger)
[15:08:49] <CaptHindsight> http://www.ebay.com/itm/SANYO-DENKI-QS1E03AA-01-AC-SERVO-DRIVE-0-163-VAC-3-PHASE-NEW-/290947032283?pt=LH_DefaultDomain_0&hash=item43bdcb64db
[15:09:13] <CaptHindsight> only 163V, but a steal if they sell for <$50 New
[15:10:06] <andypugh> CaptHindsight: A steal indeed but for brushless rather than the brushed ones he was looking at.
[15:10:16] <andypugh> (Just thought I would point that out)
[15:12:18] <CaptHindsight> thanks, read that wrong
[15:13:41] <CaptHindsight> I have some extra DC servo drives that came with that Matsuura
[15:14:29] <CaptHindsight> what voltage and current?
[15:26:02] * JT-Shop wonders how you get the powder to go into the hole your hanging the part from when powder coating
[15:28:12] <Jymmm> long tube, fill from bottom up.
[15:32:02] <JT-Shop> http://imagebin.org/265285
[15:32:31] <JT-Shop> I hang it by the center hole when powder coating and most don't have any coating inside the center hole :(
[15:33:18] <Jymmm> Yeah, I've always wondered about that.... how do you powder coat the point you are hanging from?
[15:33:33] <Loetmichel> you dont
[15:33:40] <Jymmm> same with annodize.
[15:33:46] <Loetmichel> ise a hol which gets a thread anyways
[15:33:54] <Loetmichel> use
[15:33:58] <Loetmichel> hole
[15:39:40] <JT-Shop> no threaded holes in this part
[15:39:52] <JT-Shop> guess I'll just have to touch it up with paint
[15:41:10] <Jymmm> JT-Shop: what are you baking it in?
[15:41:39] <JT-Shop> a kiln
[15:41:53] <Jymmm> can you do two runs in the kiln?
[15:42:29] <JT-Shop> I can fit several parts in the kiln
[15:42:53] <Jymmm> I mean run it twice in the kiln
[15:47:25] <t12> i guess with resolvers error wouldn't be additive either?
[15:50:12] <jdh> nice use of shipping tubes
[15:53:32] <jdh> anyone have an opinion on using a 1HP DC treadmill motor for a 9x20 spindle?
[15:59:03] <andypugh> I think Gene has done exactly that?
[15:59:42] <andypugh> (Or is gene78 's lathe smaller than that?)
[16:01:21] <jdh> or somethign like this: http://dealerselectric.com/item.asp?cID=0&PID=6900
[16:02:07] <andypugh> My 9x40 runs with a VFD and 1kW motor.
[16:02:44] <jdh> I was pretty enthused about ripping the lathe apart to convert, but after cleaning it up, refitting all the moving parts, it moves pretty well and seemed to cut OK on steel.
[16:03:09] <jdh> but, turning steel by hand seems to be ungodly boring.
[16:09:58] <andypugh> Yes, but if you sink money into CNC-converting a Chinese 9x20 you still have a Chinese 9x20.
[16:10:38] <andypugh> (Speaking from experience)
[16:12:05] <Loetmichel> hmm, invest in some new bearings and a scraping class and go for it ;-)=
[16:13:31] <andypugh> You still have no back-gears, no adequate lubrication for the spindle bearings and flimsy dovetails
[16:14:59] <Loetmichel> andypugh: right
[16:15:12] <Loetmichel> was more of a joke.
[16:15:37] <Loetmichel> wit a bit of "better than no lathe" in it
[16:15:44] <Loetmichel> i know what i am taling about
[16:16:45] <Loetmichel> i had to "work" wit that for not so short time: http://www.cyrom.org/palbum/main.php?g2_itemId=6100&g2_imageViewsIndex=1
[16:16:56] <Loetmichel> http://www.cyrom.org/palbum/main.php?g2_itemId=520&g2_imageViewsIndex=1
[16:17:18] <Loetmichel> ANY lathe is better than that, but even this one is better than NO lathe ;-)
[16:17:55] <andypugh> I had one of those.
[16:19:47] <andypugh> Then upgraded to: https://picasaweb.google.com/lh/photo/aD3U7TVt-SvekGIitO20B9MTjNZETYmyPJy0liipFm0?feat=directlink
[16:20:37] <andypugh> And now I am playing with: https://plus.google.com/photos/108164504656404380542/albums/5889085582650378897
[16:22:21] <Loetmichel> have a "new" one here. about a year. still have to get a new motor, didt found the time. got a VFD lately, tough... -> http://www.cyrom.org/palbum/main.php?g2_itemId=11462&g2_imageViewsIndex=1
[16:26:14] <andypugh> Looks rather ordinary, if I may say so.
[16:39:22] <pimperle> hi
[16:39:56] <pimperle> is there a way or even an example how to write a kinematics module as a .comp file?
[16:40:07] <pimperle> or are functions with arguments supported only in .c files?
[16:40:30] <pimperle> (it's my first linuxcnc project and my first robot and thus my first kinematics module)
[16:43:33] <DJ9DJ> gn8
[16:49:57] <andypugh> pimperle: You can't write a kins in .comp. But you can compile and install the module with comp
[16:50:47] <andypugh> I would suggest starting with trivkins and just modify the maths that defines the forward and reverse transformations.
[16:58:50] <jdh> The 9x20 was cheap. I have motors and drives. If I use the stock screws the conversion will be mostly 'free'
[16:59:32] <jdh> or $150ish for chinese ball screws and bearing mounts
[17:02:45] <jdh> If I had some tiny steppers, I'd do my Clisby lathe.
[17:03:48] <pimperle> andypugh: thanks. I already had a look at trivkins and will go that way. I also saw that comp can compile .c as well but thought using .comp files might make it easier/more concise. thanks for clarifying. :)
[17:05:09] <andypugh> As you guessed, .comp only exports one function, with no arguments.
[17:51:00] <Tom_itx> JT-Shop, use smaller stiff wire and might flow around it
[17:51:51] <JT-Shop> yea, I'll try that next time... I just used the hooks provided by the powder coating kit
[17:53:04] <Tom_itx> i used to use stiff piano wire for stuff like that
[17:53:09] <andypugh> jdh: If you have access to a mill you can make custom mounts
[17:54:16] <Tom_itx> another plane down
[17:55:46] <Tom_itx> laguardia
[17:56:01] <JT-Shop> what's going on?
[17:56:08] <andypugh> jdh: The X slide is not all that easy to convert, there isn't much room. However an 8mm ballscrew does seem to be adequate. http://www.cnczone.com/forums/mini_lathe/63621-mini_lathe_cross_slide_ballscrew_solutions-2.html#post509784
[17:59:55] <andypugh> Sounds like more of an expensive landing than a crash.
[18:46:47] <JT-Shop> http://imagebin.org/265300
[18:58:39] <jdh> cool. What are they?
[18:59:47] <jdh> andypugh: do you have any pics of your Z motor mounting?
[19:08:07] <JT-Shop> gizmos for a production line
[19:14:23] <JT-Shop> we have to make 800 units
[19:14:55] <PetefromTn> evening folks
[19:15:14] * JT-Shop puts his chef hat on
[19:21:17] <ChuangTzu_> JT-Shop: what do they do
[19:21:26] <PetefromTn> Anyone here remember the name of that little program that allows you to bend text around a radius for freeware?
[19:29:12] <cpresser> PetefromTn: inkscape?
[19:29:50] <PetefromTn> inkscape? Maybe, I remember it was a real simple program that was freeware. Lemme check it out. Thanks.
[19:36:17] <AR__> so i was wondering why my Z motor was stalling when i was dirlling
[19:36:35] <AR__> i forgot to increase the current setting on the driver..
[19:36:45] <AR__> i only had it at about 1amp
[20:50:01] <CaptHindsight> JT-Shop: we use lasers to spot cure powder coatings, you can even use a heatgun or similar to spot cure
[20:58:26] <Valen> why do you want to spot cure powder coating?
[20:59:15] <Jymmm>
[20:59:15] <Jymmm> Last Thursday, an intruder attempted to secure personal information of our registered developers from our developer website. Sensitive personal information was encrypted and cannot be accessed, however, we have not been able to rule out the possibility that some developers’ names, mailing addresses, and/or email addresses may have been accessed.
[21:00:22] <Jymmm> Apple Developer Website
[21:02:00] <CaptHindsight> Valen: think of it like an electrostatic printer
[21:02:57] <CaptHindsight> or laser printer for metals
[21:11:32] <Valen> CaptHindsight: ahh fancy
[21:17:49] <Connor> Jymmm: I just got that as well.
[21:18:01] <Jymmm> =)
[22:49:52] <Jymmm> Fuck, this is some nice work http://www.youtube.com/watch?v=BBUKMUjZAR8
[23:11:27] <FinboySlick> Jymmm: I'm FinboySlick and I approve this message.
[23:11:51] <Jymmm> whats the message?
[23:12:07] <FinboySlick> "Fuck, this is some nice work"
[23:12:12] <Jymmm> =)
[23:13:07] <FinboySlick> Jymmm: You've got great timing too.
[23:13:17] <Jymmm> how so?
[23:13:54] <FinboySlick> I was sort of bored and figured: Let's open #linuxcnc and see if anybody posted links of cool stuff being made.
[23:14:10] <Jymmm> cool =)
[23:16:31] <Jymmm> FinboySlick: Yeah, I had just bought a Leatherman Wave off CL for $35, so was just seeing what accessories there were and came across that.
[23:17:55] <FinboySlick> I have a very nice Victorinox myself... Doesn't see much use but I still always have it with me.
[23:18:53] <Jymmm> I ALWAYS carry a Tool Logic SL3, but I wanted another LM Wave to attach to my backpack.
[23:19:58] <FinboySlick> Jymmm: Heh... From our initial aquaintance, it seems to me that you are a lot more into multi-tools than I could dream to be ;)
[23:20:20] <FinboySlick> I think our first conversation was an education on pry/emergency bars.
[23:20:43] <Jymmm> SL3 has a dual blade + fire steel + whistle
[23:21:05] <Jymmm> dual being smixed striaght / serrated
[23:22:06] <Jymmm> Not sure, I think it was somethign else and I really only have a wonderbar.
[23:22:15] <Jymmm> might have been flashlights.
[23:22:30] <FinboySlick> Jymmm: Could be, it's been a few years already.
[23:22:40] <Jymmm> I did just pick up some cool Zombie Paracord though =)
[23:22:43] <FinboySlick> You might have just been part of the discussion.
[23:23:38] <Jymmm> http://www.paracordstore.com/assets/images/virus_paracord.jpg
[23:24:39] <Jymmm> http://thumbs2.picclick.com/d/w500/pict/251270262189_/550-Zombie-Paracord-Craft-Kit-4-Zombie-Colors.jpg
[23:26:38] <mrsun> vkill it!
[23:26:42] <mrsun> kill it with fire!
[23:26:59] <Jymmm> kill what?
[23:27:10] <mrsun> oh it wasnt worms
[23:27:13] <mrsun> snakes*
[23:27:20] <Jymmm> rope
[23:27:32] <Jymmm> Zombie rope =)
[23:28:08] <mrsun> so still... kill it with fire!
[23:30:02] <mrsun> its not called rope burn for nothing you know ;P
[23:30:45] <t12> hah awesome
[23:30:48] <t12> the paracord store
[23:32:12] <Jymmm> Yeah the local place where I buy it from is out of gecko (neon green + blk), so the next highest contrast was the virus (Neon grn+ORG