#emc | Logs for 2006-09-29

[00:00:17] <weyland> okay, running the ubuntu live it seems to work a little, at leasr
[00:00:31] <weyland> I'll play with this at the shop tomorrow
[00:00:35] <weyland> thank you
[00:00:44] <fenn> good luck, and tell us what happens
[00:00:51] <weyland> you know I will
[00:01:17] <weyland> long as I'm here...
[00:02:08] <weyland> I've one of the older (by now) BDI versions. when I went to make it current the other day, it couldn't find the host, so I'm guessing it's since been moved?
[00:02:25] <weyland> can i make my install current, or do I need to do a fresh one?
[00:04:38] <kdibble> hi all, cradek still here?
[00:05:02] <A-L-P-H-A> we've eaten him... just his bones are here
[00:05:09] <kdibble> I understand
[00:05:22] <kdibble> just wanted to keep him up with my progress
[00:05:25] <A-L-P-H-A> I think he's AFK
[00:05:47] <A-L-P-H-A> Waive a $50, and look needed...
[00:05:49] <kdibble> AFK: unknown acronym
[00:05:49] <A-L-P-H-A> needy
[00:05:54] <A-L-P-H-A> Away From Keyboard
[00:05:57] <kdibble> gotcha
[00:06:30] <kdibble> if you see him, let him know that the onboard video was messing with me
[00:07:05] <A-L-P-H-A> okay... you could use /msg memoserv as well. :)
[00:07:19] <A-L-P-H-A> okay... "/msg memoserv help"
[00:07:44] <kdibble> or not
[00:08:26] <kdibble> doesnt seem to work, I'll try him tomorrow
[00:08:29] <kdibble> thanks
[00:08:31] <kdibble> bye
[00:10:58] <weyland> I'm off to play, thanks boys
[00:25:45] <K`zan> After 25 pages of the manual I need to go make chips for a while :-) bbl.
[00:28:07] <A-L-P-H-A> K`zan: ?
[00:28:17] <A-L-P-H-A> reasoning is?
[01:11:17] <A-L-P-H-4> hmmmmmmmmmmmm.... just realized that I'm a little screwed on power on the stepper motors. oops.
[01:15:13] <Jymmm> DEFINATLY WORTH WATCHING --> http://www.metacafe.com/watch/252065/video/
[01:16:05] <cradek> can't
[01:16:38] <cradek> their FLASH APPLET runs in my flash player to tell me that my flash player isn't new enough
[01:17:02] <cradek> they only want windows users to see their videos
[01:26:37] <tomp> hello
[02:44:15] <A-L-P-H-4> 120VAC socket has a live/dead/earth....
[02:44:25] <A-L-P-H-4> should the case be connected to earth?
[02:44:29] <A-L-P-H-4> of a power supply?
[02:44:30] <A-L-P-H-4> A-L-P-H-4 is now known as A-L-P-H-A
[02:44:34] <jmkasunich> yeah
[02:44:44] <jmkasunich> (usually)
[02:44:53] <A-L-P-H-A> should the transformer also be touching earth? [it's housing]
[02:45:22] <A-L-P-H-A> What should be isolated?
[02:45:30] <A-L-P-H-A> how'd my lappy get killed?
[02:45:49] <A-L-P-H-A> lovely
[02:45:53] <A-L-P-H-A> stupid lappyu
[02:48:11] <jmkasunich> A-L-P-H-A: I don't know what you are building, so I'm hesitant to make any recommendations
[02:48:19] <A-L-P-H-A> rebuilding my cnc mill power supply
[02:48:28] <A-L-P-H-A> it was working, but I actually don't think it's right.
[02:51:09] <jmkasunich> ac line, to xfmr, to diodes, to cap, to drives?
[02:51:25] <sbailard_> Usually, the outsides of things should be grounded, yes.
[02:51:28] <A-L-P-H-A> yup
[02:52:07] <A-L-P-H-A> ac line, xfmr, bridge rectifier, cap, fuses, inline cap (Mariss' design), drives.
[02:52:45] <A-L-P-H-A> just wondering from the ac line, should the housing be grounded? As well as the transformer's housing, and say the heatsink for the geckos.
[02:53:20] <jmkasunich> all exposed metal should be grounded
[02:53:26] <jmkasunich> if you can touch it, ground it
[02:53:33] <A-L-P-H-A> got cha.
[02:53:47] <sbailard_> Imagine the alternative. You could have the outside floating,
[02:53:50] <sbailard_> or live?
[02:54:33] <sbailard_> This way if there's arcing in the machine, or a wire comes loose and falls against the housing, it shorts to ground.
[02:54:43] <A-L-P-H-A> sbailard_, I don't understand... but I'm taking a guess meaning, if you can touch it while it's on, and it's metal, ground it. If I can't/shouldn't touch it while it's live, don't ground that... [fuses for example.]
[02:54:53] <sbailard_> Rather than bringing the housing up to 120ACV.
[02:54:57] <jmkasunich> right
[02:55:03] <sbailard_> Right.
[02:55:11] <sbailard_> Do you have a multimeter?
[02:55:17] <A-L-P-H-A> yes
[02:55:19] <A-L-P-H-A> I have a multimeter.
[02:55:19] <jmkasunich> ground the machine frame, the box that contains the electronics, any exposed surface
[02:56:17] <A-L-P-H-A> hmm... I should get another piece of sheet metal, to form a base to mount stuff from.
[02:56:18] <sbailard_> Then when you're done, check the AC voltage between the case and ground, between the 120 live line and ground,
[02:56:20] <sbailard_> etc...
[02:56:49] <A-L-P-H-A> I'm I little scared to do that...
[02:56:54] <A-L-P-H-A> LIVE voltage testing it?
[02:57:15] <sbailard_> That sounds like fine, only make sure you don't have traces or components on your board touching the sheet metal.
[02:57:38] <A-L-P-H-A> yeah, I'll isolate the data signal stuff...
[02:58:00] <A-L-P-H-A> but see... I have kinda like two devices in the same box...
[02:58:55] <A-L-P-H-A> I have one power supply for the geckos, and then I want to mount a second device (power supply for breakout board powering pullup resistors/limit switches, etc....)
[02:59:08] <sbailard_> Well, I'm not really competent to troubleshoot something I can't see, but that should be find.
[02:59:12] <sbailard_> Fine.
[02:59:52] <sbailard_> Are they off the shelf, or did you build them?
[03:00:01] <A-L-P-H-A> which?
[03:00:31] <sbailard_> The power supplies.
[03:00:32] <A-L-P-H-A> Here's my list of things, that 'can' be grounded... the two transformers, geckos, and the case itself.
[03:00:48] <A-L-P-H-A> no, these power supplies are based off of Gecko Drive's design.
[03:00:48] <sbailard_> That sounds correct.
[03:01:14] <sbailard_> The transformers, what are they like? Do they have cases of their own, with grounding tabs?
[03:01:20] <A-L-P-H-A> I'll draw it by hand, and then scan it... easiest way for me.
[03:01:46] <A-L-P-H-A> let me find the schematics... sec.
[03:02:27] <sbailard_> A-L-P-H-A, I don't know that much about power supplies. A 'yes' or a 'no' from me in this context doesn't mean that much.
[03:03:57] <A-L-P-H-A> it has two INs, three out leads model 167L50 http://www.datasheets.org.uk/datasheet.php?article=64037
[03:04:37] <sbailard_> Opening it now.
[03:05:19] <sbailard_> ...
[03:06:56] <sbailard_> ... I'm not sure either.
[03:08:26] <cradek> what's the question about the transformer?
[03:08:43] <A-L-P-H-A> do I ground the transformer to earth?
[03:09:22] <cradek> sure, it's chassis mount, it'll probably ground itself
[03:12:18] <A-L-P-H-A> well... right now, it's kinda not... as I have everything mounted to particle board... [don't ask me why, cause I'mkinda stupid with electronics.]
[03:12:22] <A-L-P-H-A> I know enough to cause trouble
[03:12:23] <sbailard_> And the chassis is separated from the primary and secondary wires, so it won't hurt anything.
[03:12:52] <sbailard_> As long as you put it in a grounded metal box.
[03:13:12] <A-L-P-H-A> okay, drew everything now.
[03:13:19] <sbailard_> And ground your mill, and optoisolate your computer, you probably should be safe.
[03:14:01] <sbailard_> (optoisolators are probably built in to the design of your controller)
[03:14:41] <A-L-P-H-A> scanning
[03:16:49] <A-L-P-H-A> jesus this image is huge.
[03:16:49] <A-L-P-H-A> sec
[03:18:13] <A-L-P-H-A>
[03:19:31] <cradek> not sure I think the fuse should go there
[03:19:40] <cradek> if your cap is very big, you might blow it with inrush
[03:19:55] <cradek> which means you might need slow-blow fuses, which is bad
[03:20:11] <cradek> but that's the only problem I see
[03:20:11] <A-L-P-H-A> cradek, it was Mariss' design, it's a 5amp (can't remember slow/fast)
[03:20:17] <sbailard_> I don't see any obvious errors. (I didn't spot that bit with the fuse.)
[03:20:19] <A-L-P-H-A> 5amp fast blow
[03:20:38] <sbailard_> A-L-P-H-A, is Mariss' design up online somewhere?
[03:20:39] <cradek> what's the cap directly on the gecko?
[03:20:41] <A-L-P-H-A> it's off of Marriss' design schematics...
[03:20:45] <A-L-P-H-A> sbailard_ yeah... sec
[03:21:01] <A-L-P-H-A> cradek, power smoother... it's a 470uF 100V one.
[03:21:03] <cradek> A-L-P-H-A: don't care whose it is, you wanted opinions...
[03:21:11] <A-L-P-H-A> cradek, yeah.
[03:21:19] <A-L-P-H-A> cradek, just saying... not being defensive or anything
[03:21:26] <cradek> right I understand
[03:21:38] <A-L-P-H-A> at least not trying to sound like it... [I don't know better]
[03:21:39] <cradek> I think the fuse should go after the last cap
[03:21:46] <A-L-P-H-A> http://geckodrive.com/photos/Step_motor_basics.pdf
[03:21:51] <cradek> ask jmk :-)
[03:23:30] <A-L-P-H-A> the cap right after the bridge rectifier (filder capacitor) is based off of C = (80,000 * I) / V, which turned out to be something like 12000uF, or something like that.
[03:24:16] <cradek> what's the xformer voltage?
[03:24:43] <A-L-P-H-A> in 120VAC, out, I forget... I think 50VAC.
[03:25:09] <cradek> so you want about 70v on the drives?
[03:25:28] <A-L-P-H-A> yeah.
[03:29:06] <K`zan> Night folks!
[03:32:03] <tomp> goodnight
[03:36:25] <A-L-P-H-A>
[03:36:36] <A-L-P-H-A> oops... that 70VAC should be 50.
[03:37:18] <A-L-P-H-A>
[03:37:20] <A-L-P-H-A> fixed
[03:37:27] <cradek> breakout board has 5v regulation on it?
[03:37:39] <A-L-P-H-A> yeah... there's a 7805
[03:37:52] <cradek> 13v is probably too hot for a 7805
[03:38:04] <cradek> you might want a 6.3v transformer, not 9v
[03:38:22] <cradek> 6.3v are common as dirt
[03:38:23] <A-L-P-H-A> okay... I know the 7805 can handle it... if it has a heat sink.
[03:38:38] <A-L-P-H-A> true... I think I have one or two right now in my toolchest
[03:38:43] <cradek> maybe, but there's no need to overdrive it so much. heat is bad.
[03:38:51] <A-L-P-H-A> true.
[03:38:59] <A-L-P-H-A> don't want it blowing up in the middle of a run
[03:42:04] <sbailard_> A-L-P-H-A, good luck. Sorry I wasn't hugely helpful.
[03:42:11] <A-L-P-H-A> no problem.
[04:47:53] <fenn> (i might be wrong about this, but) dont ground the parport cable connector to the chassis of the motor drive box
[04:48:11] <fenn> it makes a big ground loop between the box and the computer
[04:48:33] <A-L-P-H-A> yeah, that was isolated.
[04:48:39] <A-L-P-H-A> I was just grounding the transformers.
[04:48:43] <A-L-P-H-A> not the breakout board...
[04:48:45] <A-L-P-H-A> that's isolated.
[04:48:53] <A-L-P-H-A>
[04:49:43] <fenn> gee you might as well fire up eagle at this point :P
[04:50:14] <fenn> actually, eagle sucks. use kicad
[04:50:32] <A-L-P-H-A> eagle wouldn't fit this.
[04:50:40] <A-L-P-H-A> oh the schematic would.
[04:50:51] <A-L-P-H-A> but definitely not any design... 6x4 is pretty small..
[04:51:47] <A-L-P-H-A> now I'm wondering if the bridge rectifier should be grounded...
[04:52:47] <Jymmm> huh?
[04:52:53] <Jymmm> why would you do that?
[04:54:31] <A-L-P-H-A> cause on it's base, it's metal... the top (where it has four prongs) is where the connections go.
[04:58:09] <jmkasunich> the base should be screwed to a heatsink
[04:58:38] <jmkasunich> depending on how hard you are gonna push it it might not need _much_ of a sink, but it should have something
[04:58:43] <A-L-P-H-A> it's rated for like 25amps, I'm like using 2-3amps??
[04:59:00] <jmkasunich> then just screw it to the enclosure wall
[04:59:09] <A-L-P-H-A> k.
[04:59:26] <jmkasunich> which of course means it will be grounded, and that is fine
[04:59:57] <Jymmm> and gawd help ya if you got some funky exptoc bridge where the case isn't islotaed =)
[05:00:17] <A-L-P-H-A> ackhmm... it isn't grounded right now. :/
[05:00:21] <A-L-P-H-A> I'm uber that way
[05:00:27] <A-L-P-H-A> uber newb.
[05:01:07] <Jymmm> jmkasunich I dont know why I didn't know about heat-sinking a bridge, but glad you said something. I would have never thought to ask.
[05:01:39] <Jymmm> I picked up a 40A 400V one a couple weeks ago
[05:01:43] <A-L-P-H-A> I'm trying to think of everything to ask.
[05:01:57] <A-L-P-H-A> probably for likr <$10... I'm getting $5.
[05:02:11] <A-L-P-H-A> getting = guessing
[05:02:30] <Jymmm> I paid $4
[05:02:39] <Jymmm> USD
[05:02:47] <A-L-P-H-A> I was so close
[05:02:53] <Jymmm> but I wanted a HUGE bridge (overkill)
[05:03:10] <jmkasunich> that reduces the need for heatsinking
[05:03:10] <A-L-P-H-A> bridge is the least of my worries... I think my transformer is under amped.
[05:03:23] <jmkasunich> if your gonna use the bridge right at its rating, you need to heatsink it wekk
[05:03:23] <Jymmm> I anticapate changeing the ratings of the PS as needed.
[05:03:25] <jmkasunich> well
[05:03:52] <jmkasunich> if your using 10% of the rating, just fastening it to a flat sheet of aluminum is probably enough
[05:03:55] <Jymmm> jmkasunich: Nah, I justed wanted overkill
[05:04:16] <Jymmm> if I need 40a I'm in BIG trouble =)
[05:04:39] <A-L-P-H-A> moving cars with those motors? :)
[05:04:50] <Jymmm> hot wire =)
[05:04:56] <Jymmm> but that doens't need a bridge
[05:06:02] <A-L-P-H-A> electric car, I meant.
[05:07:59] <Jymmm> Nah, that's jmkasunich job
[05:08:27] <Jymmm> he's the one that plays with "Da big shit" =)
[05:37:59] <alex_joni> hello.. anyone still around?
[05:38:03] <A-L-P-H-A> no
[05:38:12] <alex_joni> A-L-P-H-A: can you check a thing for me?
[05:38:34] <alex_joni> A-L-P-H-A: check if you reach robcon.ro or ns1.nextice.com please :)
[05:38:52] <A-L-P-H-A> checking
[05:39:28] <A-L-P-H-A> neither are working
[05:39:39] <alex_joni> ok.. thx :(
[05:40:03] <alex_joni> just started to get some answers from there
[05:41:01] <A-L-P-H-A> ohworking now
[05:59:00] <alex_joni> fenn: probing does work quite nicely in emc2
[05:59:15] <A-L-P-H-A> hey... alex_joni how's your electrical knowledge?
[05:59:21] <alex_joni> fenn: there is even a file called gridprobe.ngc which does .. a grid probing ;)
[05:59:42] <A-L-P-H-A> alex_joni, there's two methods of calculate the amount of amperage required, one is rating, and the other is via work.
[06:00:10] <A-L-P-H-A> right now... I've got this.
[06:00:50] <A-L-P-H-A> The motors are wired for speed... I have two motors that are labelled 4.2V3.5A, and one 3A and 1oHm.
[06:01:07] <A-L-P-H-A> man... I gotta find that email.
[06:04:55] <alex_joni> right
[06:05:13] <alex_joni> so around 3A @ 4V
[06:05:16] <A-L-P-H-A> well, my transformer says thisn... 100VA 2A 60Hz.
[06:05:22] <A-L-P-H-A> 115:50V CT
[06:05:30] <alex_joni> 3A @ 4V is 12W
[06:05:34] <alex_joni> roughly 12VA
[06:05:55] <alex_joni> if you multiply that by 3 you are way under 100VA which the transformer can handle
[06:05:58] <alex_joni> got it?
[06:06:20] <A-L-P-H-A> I don't know the formulas... so I'm way safe at the moment?
[06:06:45] <alex_joni> power = current * voltage
[06:07:00] <A-L-P-H-A> P = I * V.
[06:07:00] <alex_joni> lets make some simplifications just that you understand things
[06:07:13] <A-L-P-H-A> is there another Power calculation?
[06:07:13] <alex_joni> say you have 100V mains
[06:07:13] <Jymmm> A-L-P-H-A: http://www.the12volt.com/ohm/ohmslaw.asp
[06:07:22] <A-L-P-H-A> V = IR
[06:07:31] <A-L-P-H-A> alex_joni, k... 100V
[06:07:33] <alex_joni> a 100VA transformer can handle 1A on the 100V mains
[06:07:47] <alex_joni> on the output you have less voltage
[06:07:51] <alex_joni> say 20V
[06:08:00] <alex_joni> how much current can there be on the output?
[06:08:08] <A-L-P-H-A> 5A
[06:08:10] <Jymmm> * Jymmm raises hand
[06:08:46] <fenn> yes, jymmm?
[06:09:12] <Jymmm> fenn (No, I menat I knew the answer)
[06:10:49] <alex_joni> this is highly oversimplified.. but just so that you get a feeling of rough values
[06:10:58] <alex_joni> A-L-P-H-A: right..
[06:11:18] <alex_joni> A-L-P-H-A: so if your steppers take 3.5A @ 4V I think it's safe :)
[06:11:26] <Jymmm> If you REALLY want to calculate the transformer needed ---> http://www.mcitransformer.com/i_notes.html
[06:11:44] <A-L-P-H-A> what I'm confused about is... aren't I running these motors at a higher V then the sticker?
[06:11:50] <Jymmm> scan the WHOLE page
[06:12:02] <alex_joni> A-L-P-H-A: you are, but for only a tiny amount of time
[06:12:08] <A-L-P-H-A>
[06:12:16] <Jymmm> A-L-P-H-A: Stepper motors are typically ran at 20 to 25 times their rated voltage.
[06:12:18] <A-L-P-H-A> alex_joni, oh... so it's just burts, it'll be okay?
[06:12:48] <alex_joni> yup
[06:13:11] <alex_joni> Jymmm: the stepper whitepaper says 3 to 20 or so :)
[06:13:26] <A-L-P-H-A> 4 to 20
[06:13:26] <Jymmm> alex_joni which paper?
[06:13:50] <A-L-P-H-A> gecko's.
[06:14:06] <alex_joni> right
[06:14:12] <Jymmm> url and page# ?
[06:14:34] <A-L-P-H-A> Jymmm, all the gecko stepper drivers white papers say so.
[06:14:35] <alex_joni> http://www.geckodrive.com/photos/Step_motor_basics.pdf
[06:15:27] <Jymmm> and page #?
[06:15:56] <alex_joni> it's short
[06:16:04] <alex_joni> and I bet you remember how to search
[06:17:44] <A-L-P-H-A> alex_joni, okay... so if anything... for the future... lets have pretend numbers... 5AMP 2V steppers... 3 axis... so that's about 30VA... So a transformer I have, should be rated for at lesat 30VA (lets give it more, 50VA to be safer)...
[06:18:39] <alex_joni> I'd say 100 to be safer
[06:18:52] <fenn> eh?
[06:18:57] <alex_joni> fenn: what?
[06:19:01] <A-L-P-H-A> okay... so just get my desired secondary voltage... but rated for 100VA.
[06:19:03] <fenn> you arent even going to be using the steppers all the time
[06:19:17] <alex_joni> fenn: a 100VA transformer is tiny
[06:19:17] <fenn> so you can use less than 30VA, no?
[06:19:30] <alex_joni> you can .. but it might get hot :)
[06:19:49] <alex_joni> A-L-P-H-A: if you can (and there's no reason you couldn't) get a toroidal
[06:19:56] <Jymmm> Mine are running at 30V@ 3A = 90VA * 3 axis = 270VA + PS Loss
[06:19:58] <alex_joni> very small size, no problems
[06:20:20] <alex_joni> Jymmm: I doubt your motors are rated 3A @ 30V
[06:20:23] <A-L-P-H-A> the transformer though, says it's rated for 2amps... that's where it's confusing the hell outta me... the gecko white papers, say the sum of the sticker plate (2/3 or 1/3 dep. on wiring) of the amp rating.
[06:20:38] <Jymmm> alex_joni: and you would be wrong... that's exactly what I'm running them at.
[06:20:38] <alex_joni> A-L-P-H-A: the transformers are rated on the primary side
[06:20:45] <A-L-P-H-A> alex_joni, availability... don't konw where to get them locally.
[06:20:49] <alex_joni> Jymmm: I know what you are running them at
[06:20:53] <alex_joni> Jymmm: I said about rating
[06:21:02] <Jymmm> alex_joni and I said running.
[06:21:05] <alex_joni> stepper motors have a small resistance
[06:21:27] <alex_joni> so if you put 3A through them they only take something like 4V or so
[06:21:37] <alex_joni> you do drive them with more to get the current flowing faster
[06:21:43] <alex_joni> and the stepper moving faster
[06:21:51] <alex_joni> but that's not the amount of power the steppers take
[06:22:02] <alex_joni> they still take about 12VA not 90VA
[06:22:22] <Jymmm> but were tlaking the ratings of his power supply, not his motors
[06:22:23] <alex_joni> Jymmm: bet your transformer isn't rated 300VA
[06:22:54] <Jymmm> alex_joni Wanna bet $20 USD via PayPal?
[06:23:01] <alex_joni> Jymmm: sure,
[06:23:12] <alex_joni> just after you convince them to accept .ro for paypal
[06:23:14] <Jymmm> I'm using a switching PS rated at 10A
[06:23:33] <alex_joni> Jymmm: 30V 10A ?
[06:23:51] <alex_joni> that's about 2 or 3 times you need
[06:24:06] <alex_joni> but it can't hurt.. except it's more expensive
[06:24:21] <Jymmm> alex_joni Since when do you use a PS for the EXACT rating? You never put that much stress on it.
[06:24:33] <Jymmm> if you want it to last that is.
[06:24:38] <alex_joni> I usually overengineer at 1.5
[06:24:59] <Jymmm> Switching PS are cheap
[06:25:15] <alex_joni> also far away from perfect
[06:25:20] <Jymmm> hell you get 5V@30a from a PC PS
[06:25:25] <alex_joni> at least for driving another switching drive
[06:26:18] <Jymmm> anyhoo... what secondary voltage does he need (AC) ?
[06:26:35] <A-L-P-H-A> I'm doing 50VAC out... atm.
[06:28:07] <alex_joni> A-L-P-H-A: thought you don't want to change your PS?
[06:28:09] <Jymmm> Well two of these would get you 48VAC... http://www.mpja.com/productview.asp?product=7845+TR
[06:28:19] <A-L-P-H-A> alex_joni, don't... rebuilding it, to clean it up.
[06:28:34] <A-L-P-H-A> <-- check that out... that's the current setup/design.
[06:28:38] <Jymmm> Ok, two of these will get you 48VAC @ 10A
[06:28:44] <Jymmm> http://www.mpja.com/productview.asp?product=7845+TR
[06:29:10] <A-L-P-H-A> wouldn't that be 8A?
[06:29:11] <alex_joni> Jymmm: I don't see 10A
[06:29:25] <Jymmm> http://www.mpja.com/productview.asp?product=7846+TR
[06:29:25] <A-L-P-H-A> nono...
[06:29:32] <Jymmm> wrong link =)
[06:29:45] <A-L-P-H-A> okay... I see can 48VAC @ 10A
[06:29:48] <alex_joni> Jymmm: that's actually a 5A transformer ;)
[06:29:55] <alex_joni> it's not 10A
[06:29:56] <Jymmm> A-L-P-H-A: No it would be 4A, because you are double the voltage not the current
[06:30:10] <alex_joni> Jymmm: that's one of the BS of transformer manufacturers
[06:30:14] <Jymmm> alex_joni it say 10A
[06:30:15] <A-L-P-H-A> Jymmm, I was referring to your first link
[06:30:22] <alex_joni> they rate them at 12-0-12 10A
[06:30:22] <A-L-P-H-A> but yeah...
[06:30:24] <Jymmm> A-L-P-H-A so was I
[06:30:34] <alex_joni> but that means 12-0 can handle 5A, and 0-12 can handle 5A
[06:30:36] <A-L-P-H-A> it's either double the amps, or double the volts... can't be both, unless you do 4.
[06:30:41] <Jymmm> alex_joni ah
[06:30:46] <alex_joni> if you want to use 12-0-12 (24V) you still can only get 5A
[06:31:04] <Jymmm> A-L-P-H-A you wire the transformers in series to get doubel the voltage and the same current
[06:31:07] <alex_joni> I know it's a bitch.. but got bitten by it too
[06:31:28] <Jymmm> alex_joni Yeah, I gotcha ya =)
[06:31:48] <alex_joni> Jymmm: that's why it's so small
[06:32:17] <Jymmm> pics are deceiving
[06:32:30] <alex_joni> check the wire sizes
[06:32:42] <Jymmm> already closed the apge
[06:33:17] <A-L-P-H-A> alex_joni okay... so, if I'm running 70VDC... but the motors are rated as above (3.5A x 4.2V = 14.7VA) x 3 = 44.1VA, I'm okay... cause the transformer is 100VA?
[06:33:29] <alex_joni> right
[06:35:08] <A-L-P-H-A> alex_joni, so why's mariss suggesting 1/3 or 2/3 of the sum of the amp ratings stated on the motors? [just wondering]
[06:35:14] <Jymmm> lies! all lies! =)
[06:35:31] <Jymmm> BEMF
[06:35:38] <A-L-P-H-A> bemf?
[06:35:58] <Jymmm> Back EMF
[06:36:15] <A-L-P-H-A> :( ??
[06:36:31] <Jymmm> Stepper motors can generate electricity
[06:36:42] <Jymmm> and do when deaccelerating
[06:37:13] <A-L-P-H-A> so is this why I'm doubling the VA for safety?
[06:42:53] <A-L-P-H-A> hey robin_z.
[07:02:44] <A-L-P-H-A> alex_joni, thanks a lot for the information and clearification.
[07:30:53] <alex_joni> A-L-P-H-A: np
[07:33:33] <A-L-P-H-A> alex_joni, much appreciated
[09:51:14] <danex> Good Afternoon alex_joni
[09:53:04] <alex_joni> hi danex
[09:53:19] <alex_joni> danex: I tested the M110 and M120 you suggested, and it does work as expected
[09:53:28] <alex_joni> from MDI and from an program in AUTO
[09:54:13] <danex> In the Head Version?
[09:54:16] <alex_joni> yes
[09:54:50] <danex> Then the problem is in my install of the head version?
[09:54:52] <alex_joni> danex: but you must have the full path : /home/user/emc2/bin/halcmd sets signal true
[09:55:08] <alex_joni> otherwise it will use the halcmd from the installed version, which can't set the signal
[09:55:32] <alex_joni> danex: I suggest you update
[09:56:56] <danex> I have the head version Run in Place is this correct?
[09:57:21] <alex_joni> yes
[09:57:37] <alex_joni> danex: but that's from CVS, and you can get a newer version
[09:57:48] <alex_joni> go to emc2/ and issue "cvs up -dP"
[09:57:55] <alex_joni> it will get the latest changes automatically
[09:58:02] <alex_joni> you need to rebuild then
[09:59:29] <anonimasu> hm
[09:59:35] <anonimasu> hello alex
[10:00:22] <alex_joni> hi
[10:03:51] <anonimasu> what's up?
[10:04:48] <alex_joni> work
[10:06:35] <danex> Let me make sure I am correct in the install sequence, First Apt-get the Build dep for Emc2 and Emc2 axis, (this will install EMC2 if not already installed) then cvs the head version
[10:07:24] <danex> and run in place the head version
[10:08:39] <anonimasu> same as me :/
[10:08:52] <anonimasu> I hope this day ends quickly so I can go home and work on the mill
[10:25:46] <alex_joni> danex: quite
[10:29:09] <danex> If I can get internet at the plant I will let you know how it goes , they are quite picky about access,
[10:30:27] <danex> otherwise it will be late today or early tomorrow your time.
[10:30:52] <danex> have a good afternoon
[10:31:42] <danex> anonimasu, good luck with your day and your mill project
[10:41:24] <anonimasu> thanks
[12:11:48] <jepler> alex_joni: it should not be necessary to give the full path to halcmd. scripts/emc makes $EMC2_BIN_DIR the first element of the PATH, see line 90.
[12:15:10] <jepler> echo "M101 P$P Q$Q: put your code here"
[12:15:11] <jepler> export | grep " PATH="
[12:15:11] <jepler> type -path halcmd
[12:15:17] <jepler> M101 P-1.000000 Q-1.000000: put your code here
[12:15:18] <jepler> export PATH="/home/jepler/src/emc2/bin:/home/jepler/bin:/usr/lib/ccache:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/bin/X11:/usr/games:/home/jepler/groovy/bin:/usr/lib/j2se/1.4//bin"
[12:15:22] <jepler> /home/jepler/src/emc2/bin/halcmd
[12:23:34] <alex_joni> jepler: right.. forgot about that
[12:24:11] <alex_joni> anyways.. it did work OK for me..
[12:30:15] <cradek> Marc van Doornik's setup is fascinating, he's very clever to set that up
[12:32:50] <alex_joni> sub 5um precision is really something
[12:34:13] <alex_joni> actually it proves only one thing :) given enough skills & time you can do basicly anything with emc2
[12:34:32] <alex_joni> people who say you can't probably lack one or the other or both :)
[12:35:35] <skunkworks> logger_aj: bookmark
[12:35:35] <skunkworks> See
[12:40:58] <skunkworks> wow. That is pretty cool. I could see emc replacing the laser controller we have (fanuc with some specialty boards to do duty cycle)
[12:46:55] <alex_joni> cradek: guess the TP is working great if it can keep it up with sub 5um :)
[12:47:11] <skunkworks> again - warm fuzzies.
[12:47:20] <alex_joni> warm fuzzies?
[12:48:20] <skunkworks> I get an excided euphoria feeling every time I think of what emc is capible of (warm fuzzies)
[12:48:43] <skunkworks> emc2 - the anti-drug.
[12:48:47] <alex_joni> lol
[12:49:28] <skunkworks> so how much of the lead screw tracking could lesw impliment so he would not have to do that funky cam
[12:50:09] <alex_joni> actually what they Marc implemented as kins existed in emc1 as axis compensations
[12:50:18] <alex_joni> but it's dormant in emc2
[12:50:30] <alex_joni> and I'm afraid I don't understand parts of it..
[12:50:42] <skunkworks> It was over my head.
[12:52:18] <alex_joni> alter[] to EMCMOT_COMP struct, for dynamic altering
[12:52:19] <alex_joni> of compensation points by external processes, e.g., thermal comp
[12:53:45] <skunkworks> oh - thermal comp also. cool
[12:54:53] <alex_joni> skunkworks: buzzwords :)
[12:55:00] <alex_joni> it's basicly a way to add an offset
[12:55:04] <alex_joni> now that I read it :)
[13:05:29] <skunkworks> I had asked about that the other day - our big machine used the spindle temp to adjust for expantion of the spindle in the z axcisa
[13:05:33] <skunkworks> axit
[13:05:40] <skunkworks> jeez axis
[13:06:24] <alex_joni> right.. this might be done
[13:43:03] <jepler> I finally figured out why I couldn't run emc2 when I ssh'd into my machine from remote. I knew for some time that it was because the "max locked memory" was set very low (32k) but I finally figured out it is a bug in pam_ssh, the authentication module that allows X and console logins with the SSH passphrase.
[13:48:30] <anonimasu> neat
[13:52:05] <alex_joni> jepler: the one you wrote?
[13:54:08] <Jymmm> http://seattlepi.nwsource.com/business/1310AP_Japan_Battery_Recall.html
[13:57:34] <jepler> alex_joni: no, someone else wrote it
[13:58:25] <jepler> http://pam-ssh.sourceforge.net/
[13:58:47] <alex_joni> oh.. I think I remembered something I read on your blog about pam_ssh
[13:58:52] <alex_joni> and I assumed it was yours
[13:58:58] <jepler> no, just something I installed and like
[13:59:06] <jepler> and which not many people know about, it seems
[13:59:07] <alex_joni> right..
[13:59:36] <alex_joni> heh.. btw blog
[13:59:45] <alex_joni> my aether doesn't show right in IE :D
[14:00:05] <alex_joni> not that I'm very concearned about that
[14:03:20] <jepler> alex_joni: there are some old posts on cradek's blog or on mine about that
[14:03:50] <alex_joni> jepler: right.. I kinda remember, using tables instead of css
[14:03:58] <alex_joni> but I'd rather not, and screw the IE users
[14:06:01] <jepler> 40% of my blog visitors are MSIE
[14:06:04] <jepler> 6.0
[14:11:39] <Jymmm> jepler why are you using PAM?
[14:12:47] <jepler> Jymmm: I don't understand what you mean. All modern linux distributions use PAM by default.
[14:13:55] <Jymmm> That's news to me
[14:15:12] <alex_joni> Jymmm: bet you use pam_login
[14:15:13] <Jymmm> thought it was all passwd and shadow passwords now
[14:17:16] <jepler> Package: libpam-runtime
[14:17:16] <jepler> Priority: required
[14:18:48] <Jymmm> ubuntu?
[14:21:44] <alex_joni> Jymmm: debian
[14:21:56] <Jymmm> k
[14:22:15] <alex_joni> jepler: yay.. made it show in IE ;)
[14:22:45] <alex_joni> jepler: had to change the order things get written to the html
[14:23:22] <alex_joni> jepler: [html <div id=left>][_insert_html _left][html </div>] before the id=main
[14:23:31] <alex_joni> jepler: in index.cgi around line 657
[14:27:36] <alex_joni> bbl
[15:31:59] <Michel1> Hello!
[15:35:10] <skunkworks> :)
[17:06:12] <skunkworks> so there is a guy around that runs emc on his laith with a servo for a spindle? and he switches between it being an axis and a spindle within axis?
[17:09:19] <anonimasu> hm ok?
[17:09:44] <anonimasu> skunkworks: what does he do with it?
[17:09:57] <anonimasu> rotary work with mill spindle?
[17:10:20] <skunkworks> I don't know - I just heard it in passing.
[17:10:44] <cradek> yes but I forget his name
[17:11:08] <anonimasu> hm ok
[17:11:26] <cradek> he was the guy who makes some kind of bead-making accessory I think
[17:12:15] <alex_joni> I think davidf
[17:15:35] <skunkworks> cool
[17:16:09] <skunkworks> is threading in the live cd?
[17:18:31] <anonimasu> neat
[17:19:47] <alex_joni> skunkworks: parts of it
[17:20:04] <Michel1> skunkworks: I have some numbers about estop speed
[17:20:16] <Michel1> and error
[17:20:30] <skunkworks> Ok - shoot
[17:21:00] <skunkworks> * skunkworks is just a user though - not a programmer.
[17:21:09] <danex> Good Evening
[17:21:12] <alex_joni> Michel1: go on
[17:21:13] <alex_joni> hi danex
[17:22:47] <Michel1> If I estop brutally from 450mm/mn, there is about 0.02 mm error; if I stop smoothly, it takes 0.082 mm
[17:23:22] <skunkworks> what kind of machine is this?
[17:24:17] <skunkworks> (doing a english conversion because I need a perspective 450mm/m=17ipm)
[17:24:28] <skunkworks> pl
[17:24:30] <skunkworks> ok
[17:25:05] <Michel1> Those numbers are consistent on X & Y. They are for my sherline with shims and backlash tight (ie. lots of dry braking...)
[17:25:05] <Michel1> and little inertia.
[17:25:41] <danex> I just tested the Mcodes again with the path set as described still failing in the head version. I did a complete reinstall of ubuntu. and the emc2-head
[17:25:59] <alex_joni> danex: I can't imagine how that can happen
[17:26:00] <danex> Could it be related to the Motenc Drivers?
[17:26:24] <alex_joni> danex: try routing it to parport
[17:26:36] <alex_joni> or maybe even use halmeter to look at the signals value
[17:26:46] <danex> I'll be back in a few , someone just crashed another machine
[17:26:52] <alex_joni> I suspect though there might be something else overwriting it
[17:27:23] <Michel1> So the price to pay for not losing steps on estop is at most .06 mm at full speed (ie. 0.008 seconds :-) )
[17:28:10] <skunkworks> Michel1: how far would it go if you where running 5000mm/min?
[17:29:14] <alex_joni> how about on a system with phisical brakes on the motors?
[17:29:42] <Michel1> This is the max speed of my axes
[17:29:42] <Michel1> Sherline 5410 with 8760 stepper unit (vanilla sherline)
[17:29:42] <alex_joni> the robots I work with estop pretty damn hard
[17:29:55] <anonimasu> * anonimasu nods
[17:30:04] <anonimasu> depending on speed and inertia estop is hard..
[17:30:04] <alex_joni> Michel1: imagine a big (and when I say big I mean big) portal
[17:30:20] <alex_joni> something like 600kg+ moving at > 1m/sec
[17:30:35] <alex_joni> deceling that can take 2 seconds
[17:30:49] <alex_joni> hitting an estop stops it in under .2 seconds
[17:31:13] <alex_joni> needless to say it's not a very nice stop
[17:31:15] <anonimasu> bbiab
[17:31:54] <alex_joni> Michel1: I understand that for smallish machines it makes sense to do it your way
[17:32:01] <Jymmm> Back in the 300/2400 baud days, what where the names of some of the HW/SW compression algos used then?
[17:32:09] <alex_joni> but I guess you won't be able to convince people to integrate it in emc2 by default
[17:32:44] <anonimasu> for stops like that I'd use pause
[17:33:37] <anonimasu> isnt there some more requirements about estop killing off other stuff(industrial wise)
[17:33:44] <alex_joni> anonimasu: lots of them
[17:33:46] <anonimasu> to have your machines certified..
[17:33:52] <alex_joni> but probably area dependent
[17:33:54] <anonimasu> I have the papers at work I'd read it otherwise..
[17:33:56] <alex_joni> e.g. EU vs. US
[17:33:59] <anonimasu> yeah..
[17:34:10] <anonimasu> * anonimasu is doing (CE) stuff at work for another machine
[17:34:13] <alex_joni> canada is pretty crazy too from what I heard
[17:34:27] <Michel1> skunkworks: you can test it by yourself: it's a 3 line patch;
[17:34:30] <anonimasu> well, sauna time :)
[17:35:00] <skunkworks> I can just compare the abort to the estop.
[17:35:35] <skunkworks> or do the math but I don't remember what my accelleration is set to.
[17:35:36] <skunkworks> http://www.electronicsam.com/images/KandT/DSCgantry.JPG
[17:36:00] <alex_joni> skunkworks: toy size :D
[17:36:04] <alex_joni> no offense ;)
[17:36:19] <skunkworks> my machine can run over 2000mm/min
[17:36:40] <alex_joni> skunkworks: :P like I said ;)
[17:36:51] <Michel1> skunkworks: in stepgen.c 1) comment the full enable test on line 540. 2) comment addval=0 on line 742
[17:37:19] <skunkworks> alex_joni: lets see your little toy ;)
[17:38:03] <alex_joni> let me find a pic :)
[17:38:16] <skunkworks> not of your welding bots :)
[17:38:30] <skunkworks> thats cheating
[17:39:14] <Michel1> 3) add at line 556 if((*stepgen->enable == 0)&&(stepgen->addval))rtapi_print_msg(RTAPI_MSG_ERR, "make_pulses() joint:%d pos_fb:%d deltalim:%d addval:%d\n", n, (int)(*(stepgen->pos_fb)*1000), stepgen->deltalim, stepgen->addval); // MG
[17:39:14] <Michel1> alex: For such a big portal, open loop command (ie. just steppers) seems strange!!!
[17:39:55] <skunkworks> actually I have had it up to 7600mm/sec but that is just scary.
[17:40:15] <alex_joni> http://www.robcon.ro/emc/IM000398s.JPG
[17:40:27] <skunkworks> I mean 7600mm/min sorry
[17:41:02] <skunkworks> alex_joni: thay are cool
[17:41:03] <alex_joni> Michel1: AC servos not steppers
[17:41:05] <skunkworks> they
[17:41:37] <Michel1> skunkworks: to test, you just have to press manually a limit stop -> not dangerous
[17:41:46] <alex_joni> skunkworks: it seems small in a picture ,)
[17:44:00] <Michel1> Very usefull for PCB engraving ;)
[17:44:21] <skunkworks> Michel1: adding encoders to your axises solves the problem.
[17:44:26] <alex_joni> .1mm accuracy :)
[17:44:47] <alex_joni> Michel1: or just keep your change locally
[17:46:28] <Michel1> skunkworks: I understand better your concern now :-)
[17:48:28] <anonimasu> kiab
[17:48:51] <Michel1> and because you have servos (closed loop), you are not concerned by lost steps, which is *not* my case
[17:50:06] <anonimasu> Michel1: I'm more concerned with death.
[17:51:04] <anonimasu> ^_^
[17:51:20] <Michel1> skunkworks: do you use stepgen or freqgen?
[17:52:21] <skunkworks> Michel1: I have steppers on that machine.
[17:53:06] <anonimasu> skunkworks: is that the really large k&t?
[17:53:15] <alex_joni> no
[17:53:23] <anonimasu> ;)
[17:53:25] <alex_joni> anonimasu: that's thesmall one
[17:53:29] <anonimasu> ok
[17:53:43] <Michel1> skunkworks: I know, but I have no need; steppers and openloop works OK for small mills
[17:53:50] <anonimasu> is the work on the big one comming along?
[17:54:33] <anonimasu> or is it stalled/sold?
[17:54:48] <skunkworks> I was busy this summer - I have started accumulating parts though :)
[17:54:55] <anonimasu> hehe
[17:54:55] <anonimasu> nice
[17:55:19] <skunkworks> I can't wait to see that doing full 3 axis moves :)
[17:55:27] <anonimasu> hehe
[17:55:32] <skunkworks> (it was 2.5 originally)
[17:55:32] <anonimasu> me neither
[17:56:04] <anonimasu> how fast will it go?=
[17:56:06] <Michel1> anonimasu: ???
[17:56:17] <skunkworks> Michel1: the ecoders would not be used for closed loop in the servo sense - they would be just used to keep track of posision
[17:56:25] <skunkworks> on a stepper machine.
[17:56:28] <anonimasu> Michel1: http://www.electronicsam.com/images/KandT/oldkandt.JPG
[17:56:38] <anonimasu> I cant find the real pic of it
[17:56:49] <skunkworks> anonimasu: i would be happy with 200ipm
[17:56:53] <alex_joni> http://www.electronicsam.com/images/KandT/DSCCurrent.JPG
[17:57:01] <anonimasu> yeah
[17:57:14] <anonimasu> skunkworks: that's really cool!
[17:58:46] <skunkworks> thanks (the gantry?)
[18:00:52] <Michel1> skunkworks: I think both points of view makes sense. As my patch would change the old behaviour, I suggest adding a variable in the .ini , in the axis section, something like "SMOOTH_ESTOP=1" with a default value of 0
[18:13:17] <skunkworks> michell: I can see smaller machines might want to use this and making it configurable in the ini would be cool.
[18:14:50] <skunkworks> maybe bring it up on the devel mailing list and see what people think.
[18:15:51] <danex> alex_joni I can watch the signal in show. In the head version it momentary in the release it is maitained
[18:15:52] <Michel1> skunkworks: OK I'll do that and submit the patch.
[18:16:57] <Michel1> skunkworks: Sorry, that's what I was meaning.
[18:25:31] <cradek_> if you want a controlled stop I still think using estop is incorrect, since it turns off the machine
[18:25:47] <jepler> can't you get the result you want by not hooking up the .enable inputs of stepgen?
[18:25:50] <cradek_> even if you decelerate first, you cannot maintain position with the amps/choppers turned off
[18:26:39] <jepler> or using a component that lengthens the enable pulse enough to permit you to stop
[19:11:26] <NickServ> This nickname is owned by someone else
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[19:13:04] <jepler> cradek: what did we end up doing about ABC and inverse time feed mode with g38.2?
[19:13:18] <cradek> ABC is allowed
[19:13:20] <alex_jon1> alex_jon1 is now known as alex_joni
[19:13:22] <cradek> not sure about inverse time
[19:15:10] <cradek> If the probe does not trip even after overshooting the programmed point slightly, an error is signalled.
[19:15:16] <cradek> it doesn't do this either, does it?
[19:15:43] <alex_joni> I think it simply stops?
[19:16:07] <jepler> I think it makes sense to allow inverse time probing, after matt T explained the
[19:16:07] <jepler> point of IT
[19:16:12] <jepler> probing: allow rotary probe, remove minimum length restriction
[19:16:17] <cradek> the gcode aborts? I think it's supposed to
[19:17:25] <cradek> jepler: I guess I do too
[19:17:48] <cradek> jepler: might be another departure from the spec, but that doesn't bother me much
[19:18:03] <jepler> those last things I said are from the CVS log...
[19:18:29] <cradek> oh did I change it to allow already?
[19:18:38] <alex_joni> cradek: I think you did
[19:18:42] <cradek> so I'm agreeing with myself?
[19:18:52] <cradek> I'm not sure if that's reassuring or not
[19:19:14] <alex_joni> cradek agrees with cradek_ too
[19:19:42] <cradek> I also wonder if it's an error to start a probe move when the probe is already tripped (it's supposed to be)
[19:19:58] <cradek> seems one of us needs to get a probe
[19:20:00] <alex_joni> it stops right away
[19:20:09] <alex_joni> * alex_joni plans to build one :)
[19:20:12] <cradek> cool
[19:20:32] <alex_joni> http://www.indoor.flyer.co.uk/probe.htm
[19:20:35] <alex_joni> that one
[19:21:16] <cradek> neat
[19:21:16] <jepler> cradek: I thought you had one
[19:21:24] <cradek> I think I do ... somewhere
[19:21:38] <cradek> I don't recall how it mounts; my spindle is all different now
[19:21:47] <jepler> Maybe I'll write a sim-probe
[19:21:57] <cradek> SMOM (machining) maybe
[19:22:50] <CIA-8> 03jepler 07HEAD * 10emc2/docs/src/gcode/main.lyx: document g38.2 probing, including (PROBEOPEN) (PROBECLOSE)
[19:23:37] <alex_joni> yay jepler
[19:24:07] <cradek> the probe looks like an interesting project
[19:24:23] <jepler> alex_joni: we *did* test (PROBEOPEN) didn't we
[19:24:31] <alex_joni> sure did
[19:25:04] <jepler> http://www.linuxcnc.org/docs/html/gcode/main/#sub:G38.2:-Straight-Probe
[19:28:25] <alex_joni> jepler: been meaning to ask you..
[19:28:58] <alex_joni> what's the difference between http://www.linuxcnc.org/docs/html/ and http://www.linuxcnc.org/docs/devel/html/
[19:45:31] <jepler> alex_joni: in the future, docs/html and docs/*.pdf will refer to the released version, and docs/devel will refer to the development (CVS) version
[19:45:46] <jepler> but presently there is no html documentation corresponding to the released version, so docs/html is a link to devel/html
[19:46:10] <skunkworks> what is the difference between lpr and cpr in encoders - is there a difference?
[19:47:01] <cradek> I bet they're different by a factor of 4
[19:47:07] <skunkworks> would lpr be "edges"
[19:47:20] <cradek> I bet l is "lines"
[19:47:21] <CIA-8> 03jepler 07HEAD * 10emc2/docs/src/gcode/main.lyx: inverse time feed is allowed with g38.2
[19:47:28] <skunkworks> and cpr would be the holes?
[19:47:33] <cradek> c is "counts"
[19:47:38] <cradek> I think
[19:48:22] <skunkworks> hm still confused. 250 line would be 1000 counts?
[19:48:26] <skunkworks> or the other way around
[19:48:48] <cradek> I think that's right but I bet each manufacturer specifies these differently
[19:48:58] <skunkworks> I bet
[19:51:07] <cradek> I can picture a probe algorithm kind of like homing - move quickly until the probe triggers, then reverse very slowly until it untriggers and call that the probe point
[19:51:35] <cradek> otherwise you should feed at only one step or encoder count per realtime period to get full resolution
[19:52:10] <cradek> I wonder if probes "untrigger" as accurately as they trigger
[19:52:52] <cradek> if not, you could do two reversals, the last one being forward slowly
[20:00:24] <skunkworks> Your not talking to your self - I just have nothing to contribute.
[20:01:16] <alex_joni> heh..
[20:01:22] <alex_joni> cradek: it gets problematic
[20:01:32] <alex_joni> imagine scanning a few hundred thousands of points
[20:03:20] <cradek> I think the reverse-until-untrigger is no worse
[20:03:28] <cradek> two reversals is definitely worse
[20:03:52] <alex_joni> yeah.. that's what I'm thinking too
[20:04:14] <alex_joni> too bad g-code doesn't allow relative moves
[20:04:25] <cradek> sure it does
[20:05:18] <alex_joni> hmm.. then why not just do this in an O-loop ?
[20:05:33] <alex_joni> btw.. what's the relative move?
[20:05:37] <cradek> you definitely could probe a grid using a loop
[20:05:46] <cradek> you don't even need relative to do that
[20:06:00] <cradek> g9x
[20:06:38] <alex_joni> cradek: relative to clear the tripped
[20:06:43] <alex_joni> and go to the next point
[20:06:51] <alex_joni> the gridprobe is already in cvs
[20:07:21] <cradek> I see, you want relative to the probe trip point, I'm not sure that's what you'd get
[20:07:22] <alex_joni> http://cvs.linuxcnc.org/cvs/emc2/nc_files/gridprobe.ngc
[20:07:40] <alex_joni> isn't it relative to the current position?
[20:07:42] <cradek> I'm a little fuzzy on how probing works
[20:07:51] <alex_joni> cradek: how so?
[20:07:57] <cradek> I guess so
[20:10:31] <alex_joni> hmm.. so programming G91 (incremental mode), and retracting Z a bit might be enough :)
[20:10:54] <alex_joni> I still wonder why this should be in motion not in the g-code
[20:12:02] <skunkworks> what happens if you retract z a "bit" then move over and before you reach the posision the probe trips. Would you stop and move up until the probe un-trips then move up the same amount
[20:12:17] <cradek> you don't know how far to retract with your g91 to clear
[20:13:11] <alex_joni> cradek: probably retracting to the position where it barely doesn't touch is not good for any subsequent moves
[20:13:23] <alex_joni> you would still need to go up a bit
[20:13:31] <cradek> sure but you can use g91 safely then
[20:15:24] <alex_joni> * alex_joni goes to a quiet place to think about it :)
[20:15:30] <alex_joni> back later
[20:16:13] <cradek> ok :-)
[20:17:17] <skunkworks> neat idea using reletive movement.
[20:18:03] <skunkworks> still would need a contingency when the reletive movement isn't enough to clear the part for the next move.
[20:18:28] <cradek> yeah
[20:23:02] <skunkworks> that could be done on o-words also I would think
[20:23:35] <cradek> you definitely have to write the probing program with knowledge of what you're probing
[20:23:47] <skunkworks> psuedo reletive could be done also I would think (I just like the word psuedo)
[20:24:01] <skunkworks> in o-words
[20:24:04] <cradek> quasipseudorelative?
[20:24:10] <jepler> virtually relative?
[20:25:25] <skunkworks> :)
[20:27:42] <skunkworks> cradek: to a point - a generic probing routine would work - but if there is edges that are higher than your probe then yes - you have got issues.
[20:31:11] <skunkworks> * skunkworks thinks alex's "quiet place" is his hot tub
[20:32:19] <Jymmm> skunkworks YOUR hot tub?
[20:33:37] <skunkworks> I will have to admit that was a poorly worded sentence.
[20:33:54] <Jymmm> Nah, just pulling your chain a bit is all =)
[20:34:31] <skunkworks> I'm used to it :)
[20:36:28] <cradek> that'll be fixed in english 2.0
[20:37:01] <sbailard_> * sbailard_ is still running the pre-beta release.
[20:39:20] <skunkworks> Multi-lingual? Hell I can barely speak one.
[20:39:46] <sbailard_> I noticed a discussion of "Marc van Doornik's setup" above. Is it written up anywhere?
[20:40:00] <skunkworks> users list
[20:40:21] <skunkworks> on sourceforge
[20:41:15] <skunkworks> http://sourceforge.net/mail/?group_id=6744
[20:41:51] <sbailard_> Thanks. I'll look it up.
[20:42:10] <sbailard_> * sbailard_ returns to lurking.
[20:46:16] <A-L-P-H-A> logger_aj: bookmark
[20:46:16] <A-L-P-H-A> See
[20:47:16] <A-L-P-H-A> hello
[20:47:45] <A-L-P-H-A> Jymmm, jepler, cradek, skunkworks, sbailard_, alex_joni.
[20:53:01] <skunkworks> Hi A-L-P-H-A