#emc | Logs for 2008-07-04

[03:27:57] <chr0n1c> so i was verifying this program the other night and in the middle of it i noticed where a 90 degree corner in the toolpath had been translated to a radius in the axis PATH display. every other program i verified the code in did not display the radius including axis' own GCODE display. is this something that has been observed before?
[03:31:43] <cradek> are you talking about the backplot or preview?
[03:32:35] <chr0n1c> the preview was correct as per the program g code.. i was running it realtime with my motors turned off.. and the live toopath backplot was not correct...
[03:32:58] <chr0n1c> i can share the code if needed
[03:33:01] <cradek> the backplot will show the rounded/blended corners but the preview will not.
[03:33:30] <chr0n1c> as per planned?
[03:33:34] <cradek> also the backplot is less smooth than the real machine motion
[03:33:53] <chr0n1c> but this was supposed to be two lines intersecting at a 90
[03:34:12] <cradek> I'm only guessing because I didn't see it...
[03:34:19] <chr0n1c> and it cut a trace on the circut board i was milling right in half so it had me concerned
[03:34:35] <cradek> oh, so it was the real motion
[03:34:40] <chr0n1c> i should have done a screenshot but i had to go to work...
[03:34:45] <chr0n1c> yes real motion...
[03:34:54] <cradek> for pcbs do you use G64 Pxxx (tolerance mode)?
[03:35:10] <chr0n1c> well, not real motion, it would have been real motion had my motor drivers been switched on
[03:35:11] <cradek> I bet you are getting more blending than you want. maybe because your accel is set low.
[03:35:33] <cradek> if you can do it again, I'd like to see a screenshot - I'm only guessing now.
[03:36:08] <chr0n1c> i will run it again and take a shot.. i'll let it run tongiht while i'm snoozing
[03:36:32] <chr0n1c> i might do the ink pen and paper test as well to see if it comes out in the actual motion
[03:36:48] <chr0n1c> *should do the ink/paper test
[03:39:09] <chr0n1c> the code i was running was from pcb_gcode and then i used codeshark to rotate the x/y plane 90 degrees...
[03:39:26] <chr0n1c> the code looked right...
[03:39:57] <SWPadnos> out of curiosity, how did it cut a trace when the motors were switched off? (or was that separate runs?)
[03:40:18] <cradek> if I understand correctly, the backplot line went through a trace unexpectedly
[03:40:28] <chr0n1c> the virtual trace that would have been milled had the program been run with the motors on
[03:40:47] <chr0n1c> ;)
[03:40:59] <chr0n1c> a hypothetical trace if you will
[03:41:01] <chr0n1c> lol
[03:41:20] <SWPadnos> the backplot is sampled at a much lower rate than the motion actually happens
[03:41:44] <SWPadnos> if you lower the feed rate override near some corners, you may see that they're sharp
[03:41:54] <chr0n1c> SWPadnos, you think it's just a resolution thing?
[03:42:01] <chr0n1c> on my screen*
[03:42:05] <SWPadnos> sampling, not resolution
[03:42:43] <chr0n1c> ok.. that would make sense. maybe i shoulda waited until i did an actual motion test to bring it up.
[03:42:45] <SWPadnos> AXIS samples 10 or 100 times/second, so if the corner is turned between samples, you'll see a cut corner
[03:42:57] <SWPadnos> even though the actual path was square
[03:43:03] <SWPadnos> (or mostly square anyway)
[03:43:18] <cradek> so it could be bad gcode [fixable], bad sampling [no problem], or excessive blending [fix with G64 Pxxx]
[03:43:41] <cradek> I don't want to guess which it is
[03:43:43] <SWPadnos> or it could be an error, but that seems less likely than one or more of the above :)
[03:43:51] <chr0n1c> yeah i just ran across the g64 when i was looking for related problems.
[03:44:05] <cradek> sure, or an emc bug I guess, but that's pretty unlikely
[03:44:52] <chr0n1c> i was just wondering if anyone had ran across the behavior before. i wasn't making any conclusions yet!
[03:45:22] <cradek> I've seen all three problems at various times :-)
[03:45:35] <chr0n1c> if anything i would have guess that codeshark screwed up the math when it rotated the xy plane
[03:46:00] <chr0n1c> but i'll run the motors tomorrow with an ink pen ;)
[03:46:22] <cradek> the preview would generally show any bogus gcode
[03:46:35] <SWPadnos> or slow down the travel rate near a corner and see if it sharpens up :)
[03:47:33] <chr0n1c> well thanks for the input cradek, SWPadnos...
[03:47:43] <SWPadnos> sure
[03:47:48] <cradek> welcome
[03:47:50] <SWPadnos> sounds like bedtime for me. good night
[03:47:53] <cradek> me too.
[03:47:58] <chr0n1c> cya!
[03:48:08] <chr0n1c> happy 4th n stuff
[11:56:28] <BigJohnT> I hope I didn't screw up, I clicked on upgrade to 8.04 LTS in Software Updates :(
[11:57:28] <archivist> ah well, please tell and report the result
[11:58:21] <BigJohnT> will do, I see that 115 updates are available now and the upgrade is not even done
[12:00:08] <BigJohnT> I should quit clicking on things this early in the morning on a holiday
[12:08:27] <jepler> BigJohnT: you did that on a 6.06 + emc2 machine? let us know how that goes ..
[12:08:48] <BigJohnT> yep :)
[12:09:03] <BigJohnT> looks like it will take a while
[12:11:07] <BigJohnT> support for some applications ended but EMC is not listed...
[12:12:46] <jepler> I don't know whether you'll get a working emc2 after the update (probably not), but the other problem is that you can't edit the docs with the version of lyx in 8.04.
[12:12:53] <jepler> (it will write out a file that can't be read on 6.06 machines)
[12:13:34] <BigJohnT> It just gave me a chance to bail out :)
[12:14:16] <jepler> I'd chicken out, given the chance
[12:14:28] <BigJohnT> It said it would take 19 hours and 31 minutes to download 574 new packages and upgrade 918 packages
[12:21:48] <BigJohnT> * BigJohnT says cluck cluck :)
[12:38:48] <Roguish> good morning and happy holidaze!
[12:39:10] <archivist> Ill check my logs to check for BigJohnT swearing on Monday
[12:39:46] <Roguish> jepler, recall you and others were helping find my Axis realtime delay error? i think it's related to classicladder somehow.
[12:40:18] <Roguish> using the same configuration, i backed out all cl stuff and do not get the error.
[12:40:58] <Roguish> i'm going to slowly add back in the cl and see where it starts to error.
[12:41:48] <Roguish> i know there is a cl graphics error already. after running with the cl gui for a while, the gui dies.
[12:42:53] <BigJohnT> archivist: I bailed out
[12:43:14] <archivist> chicken!!!!!!!!!!!!1111111
[12:43:37] <BigJohnT> YES and also the problem with lyx
[12:43:49] <archivist> I hates upgrades sometimes
[12:44:11] <archivist> apt-get segfaults on the debian box Im on now
[13:44:48] <micges> hi all
[13:45:21] <alex_joni> hi
[14:50:20] <DaViruz> Greetings. How much HD space is needed for a installation from the standard ubuntu emc2 cd?
[14:53:07] <archivist_emc> Ive added a bit but 3543304 1k blocks used on my box (I have apache and mysql taking a lot)
[14:54:10] <archivist_emc> eg my use dir is 1022852 of that
[14:58:04] <DaViruz> hmm, that sounds kind of large coming from a 700MB iso, but i guess installation onto a 2GB compact flash is a no go then
[14:59:15] <archivist> dunno Im likely to have selected more then the minimum during the install
[14:59:52] <pjm> ello
[14:59:58] <archivist> Ive added some perl modules as well iirc
[15:01:14] <archivist> DaViruz, probably worth a try at that size
[15:01:35] <DaViruz> okay, i'll give it a shot then. thanks
[15:02:30] <SWPadnos> you should be able to get an installation onto a 2G disk, but it isn't as straightforward
[15:02:52] <SWPadnos> you'd have to start with the alternate or server CD, then install EMC2 using the install script
[15:04:19] <archivist> DaViruz, just remembered another large install on mine was the dev utilities so should easily fit
[15:04:30] <SWPadnos> I'm not sure how much of the whole desktop environment you get from that (things like openoffice, firefox, etc)
[15:05:22] <archivist> and man pages amd languages , there a lot that can be thrown
[15:05:59] <DaViruz> SWPadnos: well, i don't need any of that on my cnc controller.. :-)
[15:06:43] <SWPadnos> right :)
[15:07:53] <SWPadnos> it looks like the package doesn't directly depend on any of the large metapackages (in fact, it doesn't directly depend on gnome or any UI)
[15:09:38] <jepler> SWPadnos: it does pull in python2.5-gnome2 libgnomecanvas2-0 libgnomeprint2.2-0 libgnomeprintui2.2-0
[15:09:55] <SWPadnos> right. I assume those depend on some UI / gnome elements
[15:10:04] <SWPadnos> (but they're not direct dependencies)
[17:25:28] <jepler> skunkworks: http://axis.unpy.net/01215190154
[17:27:27] <mdynac> i have a quick question for some g-code guru, as i am quite the rookie....
[17:28:31] <jepler> mdynac: ask away
[17:28:41] <jepler> hopefully you'll find that there's a guru in the room
[17:28:48] <jepler> mmmm beets http://emergent.unpy.net/index.cgi-files/sandbox/img_7476-medium.jpg
[17:29:27] <mdynac> how would i repeat a 3 line program over and over...
[17:29:59] <tomp> jepler: what kind of time is involved in making that pcb ( from end of pcb design to board milled & drilled )? I'm wondering the efficacy of milling prototypes vs breadboard vs commercial service.
[17:30:49] <SWPadnos> breadboard isn't so great for SMT parts (though that board doesn't use any), and even a few hours is less than a day or two
[17:31:03] <SWPadnos> which is as fast as you can get a quick prototype
[17:31:05] <jepler> tomp: oh it must have been less than an hour, and I still don't have "the process" down
[17:31:34] <tomp> great, that says a lot thx all
[17:31:46] <jepler> mdynac: let me see if I can whip up an example along those lines..
[17:32:55] <archivist> but if a complex board for production I would use a commercial service (pth and smt and small features)
[17:33:14] <tomp> loop examples using Owords http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Oword ( not the Oh*ll Osh&t Ocr@p words :)
[17:33:28] <SWPadnos> oh - milling isn't suitable for production, unless you're producing for yourself and some riends
[17:33:32] <SWPadnos> friends
[17:34:37] <jepler> mdynac: http://emergent.unpy.net/index.cgi-files/sandbox/forever.ngc
[17:35:07] <tomp> archivist SWPadnos I agree but never made pcbs for smt so far ( or poked myself in eye with pointed stick on purpose )
[17:35:40] <jepler> some smt parts are doable by anyone who can solder through-hole competently (SOIC); but small stuff gives me fits.
[17:35:46] <archivist> tomp PCB design was the day job a few years ago
[17:36:14] <tomp> ooh (AXIS.stop). nice! is there an AXIS.start and/or pause or color=green?
[17:36:18] <jepler> tomp: no
[17:36:35] <tomp> and re: pcbs' i agree i'm still ttl :)
[17:36:58] <jepler> tomp: well, there's kind-of a "start"; you can (AXIS,hide) and (AXIS,show) to suppress part of the gcode in the preview
[17:37:08] <tomp> thx, thats real cool
[17:37:34] <archivist> hand soldering smt 60 pin ics is "fun"
[17:38:32] <tomp> i had just done 4 of pminmo's stepper drivers each with a half dozen smt caps and res... too damn small for these old eyes ( but i did it and they work :-P
[17:38:34] <SWPadnos> you haven't lived until you've done (a) 0603-sized dual LEDs and (b) 8-resistor respacks in 0402 spacing
[17:38:58] <mdynac> jepler: thx
[17:39:19] <jepler> mdynac: do you follow what's going on in that file? or is there a part I can clarify?
[17:43:01] <mdynac> jepler: i get it, cool. is that standard run of the mill g - code, or is it unique to emc.....
[17:43:18] <jepler> mdynac: I think it's emc-specific.
[17:44:50] <mdynac> well it is too cool, the more i play with emc the better it becomes...... and there is a good possibility that the emc wire edm may be back online....
[17:46:42] <jepler> that would be awesome -- keep us posted
[17:46:50] <anonimasu> NICE :)
[17:47:27] <anonimasu> tomp: flux is they key to smt stuff
[17:54:43] <jepler> bbl
[18:45:19] <jepler> cradek: have a link to that high-speed spindle you showed me the other day?
[18:51:23] <jepler> cradek: is it "wolfgang engineering"? http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=180258202157
[18:53:21] <SWPadnos> jepler: http://stores.ebay.com/Wolfgang-Engineering ??
[18:53:32] <SWPadnos> I think I've heard that his spindles are good
[18:53:40] <SWPadnos> but it could be someone else :)
[18:53:47] <jepler> SWPadnos: yeah that looks a lot like what cradek showed me
[18:54:00] <SWPadnos> no motors on those though
[18:54:16] <SWPadnos> or, $39 for a motor
[18:54:18] <jepler> yeah, he has an inexpensive motor though
[18:55:56] <jepler> I wonder if the 100W microcontroller lamp dimmer I recently designed works with inductive loads..
[18:56:34] <SWPadnos> you could try it with a fan of suitable size (or a dumb dremel)
[19:00:30] <dmess> hi all
[19:04:25] <chr0n1c> yo
[19:19:05] <dmess> sup C
[19:19:44] <dmess> theres a pic of my new machine on imagebin.org
[19:19:48] <chr0n1c> oh, it's kinda rainy here...
[19:20:20] <chr0n1c> the big puddle in the middle of our shop floor was back today
[19:20:27] <chr0n1c> i named it lake bragg after the boss
[19:20:37] <chr0n1c> he thought that was hilarious!
[19:21:26] <chr0n1c> which pic might it be dmess?
[19:21:59] <chr0n1c> The 50 latest images added...
[19:21:59] <chr0n1c> Up to 1000 images will be kept in our database for any one time. Additionally we will only retain the image for up to 7 days.
[19:22:29] <chr0n1c> ahh i see your name ;)
[19:22:56] <chr0n1c> a mini lathe?
[19:29:38] <chr0n1c> i saw a bunch of square hot roll steel tubing hiding in the corner of the shop today and i think i need to build a lathe with it
[19:30:43] <anonimasu> * anonimasu nods
[19:30:45] <anonimasu> same with me
[19:31:03] <anonimasu> im thinking steel base and a linear slide for the carridge
[19:35:31] <anonimasu> with endplates to mount the spindle assembl
[19:35:33] <anonimasu> y
[19:55:30] <anonimasu> hm..
[19:55:41] <anonimasu> does anyone have a idea about what kind of cutting forces you can expect on a lathe?
[19:56:06] <jmkasunich> I read a formula once that seemed to make sense
[19:56:13] <chr0n1c> depends on how big of cuts you want to take and what materials you would be cutting
[19:56:25] <jmkasunich> basically you take the spindle power, and divide by the surface speed
[19:56:47] <anonimasu> hm. for a small lathe :p
[19:56:48] <SWPadnos> that would be the maximum
[19:56:56] <archivist> sandvik book has data iirc
[19:57:00] <anonimasu> 1kw spindle.. or so..
[19:57:10] <anonimasu> 500mm travel
[19:57:42] <anonimasu> tiny :)
[19:57:46] <jmkasunich> 1kw = 1000 N*m/sec
[19:58:11] <alex_joni> hi all
[19:58:15] <jmkasunich> cutting speeds I only know in feet/min - ~100 for steel
[19:58:38] <jmkasunich> I think that works out to about 0.5m/sec
[19:58:44] <anonimasu> looking for some data to give the fea program to calculate stiffness of this
[19:58:52] <jmkasunich> so the cutting force would be about 2000N
[19:58:55] <archivist> also depends on tool geometry
[19:59:21] <anonimasu> * anonimasu nods
[19:59:52] <anonimasu> 2000N sounds like doable with a square tubing.. and capped ends..
[20:00:15] <SWPadnos> 2000N or less
[20:00:18] <anonimasu> even without internal bracing..
[20:00:18] <jmkasunich> roughly 400 lbs
[20:00:21] <anonimasu> yep
[20:00:22] <anonimasu> 200kg..
[20:00:24] <SWPadnos> that's the max the spindle can apply
[20:00:27] <anonimasu> ~ about..
[20:00:33] <anonimasu> a bit less..
[20:00:34] <anonimasu> :)
[20:00:43] <jmkasunich> true, so in theory 2000N is a nice conservative number
[20:00:51] <SWPadnos> yep :)
[20:01:00] <anonimasu> (I were thinking of getting fancy and adding a bar from end to end so you could tighten it to make the lathe bed stiffer..
[20:01:02] <jmkasunich> but in practice, you want it stiff enough to not vibrate under an interrupted cut, etc
[20:01:13] <archivist> watch for springy ness/stiffness of a bed
[20:01:18] <jmkasunich> preload does not make things stiffer
[20:02:40] <anonimasu> if you fix the endplates togther it should make it stiffer, or am I completely wrong?
[20:03:00] <BigJohnT> anonimasu: are you building a lathe from scratch?
[20:03:09] <anonimasu> BigJohnT: yeah
[20:03:16] <BigJohnT> cool
[20:03:19] <anonimasu> BigJohnT: I want a really tiny one..
[20:03:27] <anonimasu> BigJohnT: I've got one big and one really big and one small..
[20:03:46] <anonimasu> :P
[20:03:55] <jmkasunich> 1kw spindle is not a tiny lathe
[20:04:05] <anonimasu> 500mm of bed is a tiny lathe ;)
[20:04:25] <BigJohnT> how many hp is 1 kw?
[20:04:31] <jmkasunich> 1.3 or so
[20:04:33] <anonimasu> 1.36
[20:04:33] <archivist> fill tube to damp it
[20:04:43] <anonimasu> with what?
[20:04:44] <BigJohnT> small but not tiny
[20:04:46] <anonimasu> concrete?
[20:04:48] <jmkasunich> http://www.mini-lathe.com/
[20:04:55] <anonimasu> ew.
[20:04:55] <chr0n1c> sand and silicone!
[20:04:57] <jmkasunich> 250mm
[20:05:05] <alex_joni> molten lead
[20:05:12] <jmkasunich> heh
[20:05:12] <anonimasu> lol
[20:05:49] <BigJohnT> expanding cement
[20:06:11] <chr0n1c> i'd fill mine with jelly
[20:06:18] <jmkasunich> grape?
[20:06:23] <anonimasu> *sigh*
[20:06:50] <chr0n1c> well, i like strawberry
[20:06:56] <BigJohnT> anonimasu: why not one big box tube with a plate on top for ways
[20:06:59] <dmess> anon... my machine should end up with 150mm z and about 50mm dia. on motors... the crosslide can be moved but i dont have a tailstock yet .. if everyon could keep an eye open i'd appreciate it
[20:07:13] <chr0n1c> but yes, i have some steel tubing in mind to build a small lathe
[20:07:20] <anonimasu> my idea is tho have a square tubing 100x200mm
[20:07:27] <anonimasu> as thick walled I can get..
[20:07:35] <anonimasu> then a linear slide on top
[20:07:44] <dmess> that could get $$$
[20:07:44] <BigJohnT> * BigJohnT gets his calculator out
[20:08:00] <dmess> 4 x 8
[20:08:11] <archivist> * archivist would get a lathe bed from a scrap yard
[20:08:14] <anonimasu> linear slides arent all that expensive..
[20:08:18] <BigJohnT> Thats some big tubing
[20:08:29] <anonimasu> 100x200mm?
[20:08:38] <BigJohnT> the problem with tubing like that is it is not square or flat
[20:08:41] <jmkasunich> anonimasu: you'll very quickly spend more than the cost of a mini-lathe
[20:08:49] <anonimasu> well, I can fit it in the big mill of mine
[20:09:01] <chr0n1c> dont buy a harbor freight mini lathe!
[20:09:06] <dmess> but wall section would be in the 3/8 ( 10 mm) range correct??
[20:09:06] <anonimasu> oh.. I had a small lathe..
[20:09:14] <fenn> i think that formula's wrong.. as cutting radius approaches zero, cutting force goes to infinity
[20:09:15] <anonimasu> I think 5-8mm
[20:09:21] <chr0n1c> i went through 4 of them and didn't even get a full revolution of the spindle before they died
[20:09:23] <jmkasunich> fenn: what formula?
[20:09:26] <BigJohnT> you would be better off with a weldment then normalize then machine flat
[20:09:30] <fenn> er, not cutting force, but maximum possible force the spindle can exert
[20:09:46] <fenn> jmkasunich: power/surface speed
[20:09:52] <dmess> yes.. as surface speed goes to 0
[20:09:52] <anonimasu> normalizing isnt all that easy to do unless you have a nice big oven -_-
[20:09:52] <jmkasunich> its not wrong
[20:10:15] <dmess> but NOTHING cuts at 0 sfm
[20:10:15] <jmkasunich> as the radius approaches zero, you have to increase speed to maintain constant surface speed
[20:10:18] <chr0n1c> a big oven or a big bonfire
[20:10:22] <jmkasunich> increase speed = reduce torque
[20:10:39] <dmess> or a big lobster pot
[20:10:46] <jmkasunich> the reduced torque and the reduced radius cancel out, and the force remains constant
[20:10:48] <anonimasu> heh.. I can get hot drawn/cold drawn steel..
[20:11:01] <anonimasu> like, when I buy it..
[20:11:08] <anonimasu> (im all into theorizing right now..
[20:11:28] <dmess> its imaginary... it dont happen in the real world
[20:11:33] <jmkasunich> how hot do you have to go to normalize?
[20:11:45] <dmess> what material
[20:12:00] <BigJohnT> kinda depends on how hot you welded it but 500 works well
[20:12:00] <chr0n1c> right up until it's about to go liquid... then freeze it
[20:12:05] <BigJohnT> f that is
[20:12:17] <dmess> many aluminums need TIME to normalize.... you cant rush it
[20:12:29] <alex_joni> chr0n1c: not for normalizing
[20:12:34] <fenn> anonimasu: if you're going to mount slides to steel tubing, probably should read this: http://lmwatts.com/straightedge.html
[20:12:41] <alex_joni> for that you need a long T8/5 time
[20:13:04] <alex_joni> jmkasunich: there is a special variable used when talking about these things and it's calle T8/5
[20:13:07] <anonimasu> fenn: my 200mm facemill should make a long flat surface
[20:13:10] <chr0n1c> yeah, ford used to let engine blocks rust in a field for years... i don't know if they still do
[20:13:15] <alex_joni> it means the time it takes the metal to cool from 800C to 500C
[20:13:26] <alex_joni> (probably doesn't quite apply to alluminum)
[20:13:54] <alex_joni> fenn: speaking of which.. I wonder how les is..
[20:14:00] <jmkasunich> I assume we're talking about steel weldments here...
[20:14:05] <anonimasu> fenn: or I can throw it at the grinding shop we've got in town
[20:14:06] <dmess> high strength steel pre- h/t 350 F post h/t BUT pre- shot-peen 500 f... post s/p 375 max...
[20:14:10] <jmkasunich> I may be making one in the future
[20:14:19] <fenn> anonimasu: cheater :)
[20:14:29] <anonimasu> fenn: lol
[20:14:36] <anonimasu> fenn: whatever get's the job done :)
[20:15:44] <alex_joni> jmkasunich: not necessarely welding..
[20:15:50] <alex_joni> steel treatment in general
[20:15:55] <chr0n1c> i w as thinking i'd weld up a tube bottom frame, throw it on our 40" thompson water grinder to get it all square and flat then start bloting stuff to it
[20:16:00] <BigJohnT> I put them in an old oven to normalize
[20:16:02] <alex_joni> it's usually done to relief stress after welds..
[20:16:06] <chr0n1c> bolting *
[20:16:07] <anonimasu> chr0n1c: that's a plan
[20:16:11] <anonimasu> the main reason for building a machine like this is that it would probably be easier then buying a normal little lathe
[20:16:14] <alex_joni> you heat it up to 800C+ then let it cool down slowly
[20:16:17] <jmkasunich> BigJohnT: kitchen oven?
[20:16:27] <BigJohnT> yes
[20:16:29] <anonimasu> fitting ballscrews is a pain :)
[20:16:30] <jmkasunich> 800C is fsckin hot for home stuff
[20:16:37] <alex_joni> jmkasunich: baker's oven is probably better
[20:16:46] <BigJohnT> not the one in the kitchen :)
[20:16:51] <dmess> i boiled Al DASH 8 nose gear parts in PEI a few yrs ago to avoid the 18 day trip to oakville for stress relief...
[20:17:00] <alex_joni> kitchen oven won't get you that high.. but still better than nothing
[20:17:29] <BigJohnT> I only go to 500F
[20:17:35] <chr0n1c> i like the backyard bonfire idea...
[20:17:41] <BigJohnT> for hot roll weldments
[20:17:41] <alex_joni> if you want the steel to get really hard you can do the reverse: heat it up, then cool it in oil or water
[20:17:46] <anonimasu> fenn: I'd really like to learn how to scrape ways but learning it takes a shitload of time
[20:17:52] <chr0n1c> throw the frame in there for about 25 minutes
[20:18:15] <dmess> i normaliz all my home made tooling in the ove.. leave it in for a month of cooking.. my angle plate has NEVER moved .0001" since it was ground...
[20:18:19] <anonimasu> fenn: and lots of hand work.. and well, lots of physical labour dosent work very well for me :/
[20:18:31] <jmkasunich> heh
[20:18:51] <jmkasunich> I scraped the ways on my shoptask before I put it back together after moving it - not loads of fun
[20:18:55] <BigJohnT> the guy that taught me told me if I don't crank up the heat too much when welding the oven will do the trick
[20:19:11] <anonimasu> -_-
[20:19:17] <dmess> bond fire is too uneven itl twist to shit... for sure
[20:19:23] <fenn> we just need a way scraping robot
[20:19:27] <anonimasu> yep
[20:19:48] <alex_joni> BigJohnT: that depends what you want
[20:19:54] <dmess> im right here but i AINT cheap..
[20:19:56] <anonimasu> jmkasunich: how long did that take?
[20:19:58] <alex_joni> most of the time you don't want to crank up the heat in the weld
[20:20:06] <jmkasunich> two days (a few hours each day)
[20:20:10] <anonimasu> ok
[20:20:15] <alex_joni> besides good penetration, you also get a hardened heat-influenced zone
[20:20:17] <dmess> i always welh HOT
[20:20:18] <anonimasu> that's not too bad
[20:20:20] <alex_joni> and that one usually cracks
[20:20:29] <als> you can use lower temps and longer time works the same
[20:20:41] <BigJohnT> alex_joni: hows that?
[20:20:49] <dmess> mig?? or Tig??
[20:20:57] <alex_joni> BigJohnT: lots of energy into the workpiece will heat up the area around it
[20:21:07] <alex_joni> if the part is big heat will be dissipated fast
[20:21:15] <alex_joni> and the temp will drop fast
[20:21:15] <jmkasunich> anonimasu: http://jmkasunich.com/cgi-bin/blosxom/shoptask/scraping-12-17-06.html and http://jmkasunich.com/cgi-bin/blosxom/shoptask/scraping-12-18-06.html
[20:21:31] <alex_joni> so that works like a regular hardening in air (heat it up, allow it to cool fast)
[20:21:31] <dmess> yes.. thats what i do... pour it in and MOVE on... get outta there
[20:21:37] <anonimasu> anyone got a better idea about
[20:21:44] <als> the molecule needs a longer time change forms at lower temps that all
[20:21:46] <anonimasu> how to make a nice base?
[20:21:54] <BigJohnT> mig
[20:21:56] <anonimasu> maybe I should just buy a grinder :P
[20:22:04] <alex_joni> BigJohnT: this mostly refers to the 3-4mm area around the weld pool
[20:22:10] <alex_joni> talking cross-section here
[20:22:17] <BigJohnT> ok
[20:22:18] <fenn> anonimasu: how precise does it have to be?
[20:22:19] <anonimasu> (lots of places sell them here)
[20:22:36] <anonimasu> they usually do nc grinding nowdays so there are lots of manual machines
[20:22:42] <dmess> but sometime the dont make the curve... and actually transform when welding slon and cool
[20:22:42] <alex_joni> BigJohnT: sorry.. it seems it's called heat affected zone in english
[20:22:55] <alex_joni> http://en.wikipedia.org/wiki/Image:Welded_butt_joint_x-section.png
[20:22:55] <fenn> anonimasu: i'm thinking you could use shims and moglice potting compound to level the rails
[20:23:07] <fenn> instead of grinding the surface flat
[20:23:47] <anonimasu> hm.. a grinder would be 200eur :p
[20:23:56] <fenn> eh?
[20:23:58] <anonimasu> that looks like it's not in crap condition with a magnetic talbe
[20:23:58] <dmess> but it..
[20:24:00] <anonimasu> table..
[20:24:10] <anonimasu> (lots of places have closed here during the last years)
[20:24:13] <alex_joni> BigJohnT: heat treatment usually gets rid of that, so your oven is mostly usefull :D
[20:24:25] <BigJohnT> :)
[20:25:11] <anonimasu> http://www.blocket.se/vi/15787583.htm?ca=1_12_s
[20:25:32] <BigJohnT> alex_joni: I don't see the burned finger in the picture, I always have one :)
[20:26:01] <alex_joni> BigJohnT: I'll send you a pic of my eyes, when I do some welding next time :/
[20:27:14] <alex_joni> BigJohnT: did some nice Tandem welding this week (basicly 2 x MIG)
[20:27:15] <BigJohnT> I got burned once looking away from the welder when I worked in a shipyard
[20:27:26] <alex_joni> sideways is the worst..
[20:27:48] <BigJohnT> we were inside of the aluminum uptakes all shiny
[20:28:04] <alex_joni> ouch :D .. that's why I got myself a nice pair of goggles
[20:28:14] <BigJohnT> that hurt
[20:29:10] <alex_joni> I started to get used in dealing with that
[20:29:33] <alex_joni> couple of eyedrops, a vile of painkiller .. and a good nights sleep
[20:29:47] <BigJohnT> ouch
[20:29:48] <alex_joni> and if you do wake up in the night.. the most important thing is to keep your eyes closed
[20:29:52] <alex_joni> no matter what..
[20:30:01] <SWPadnos> just pee carefully
[20:30:14] <SWPadnos> (or the wife gets annoyed)
[20:30:16] <alex_joni> SWPadnos: just pee around
[20:30:27] <alex_joni> works like a sonar
[20:30:33] <jmkasunich> lol
[20:30:36] <chr0n1c> oh my
[20:30:42] <SWPadnos> oh, happy belated anniversary (I think)
[20:30:46] <alex_joni> lol
[20:30:54] <anonimasu> :)
[20:31:00] <SWPadnos> well, that works once you get to the bathroom
[20:31:15] <alex_joni> yeah, well.. it would suck to use the sonar on the way
[20:31:30] <SWPadnos> scanning for the bedroom door is not recommended
[20:31:35] <alex_joni> ROFL
[20:31:56] <chr0n1c> this one time at welding camp...
[20:32:09] <alex_joni> BigJohnT: what I also do is take a wet handkerchief and put it on my eyes
[20:32:32] <alex_joni> together with an eyeflap or whatever that thingie you use in airplanes is called
[20:32:46] <anonimasu> that grinder that costs 250 eur has a bad cylinder(bad seals) from the sounds of it
[20:33:11] <BigJohnT> I keep my hood down and long sleeve shirt on even if it is hot
[20:33:31] <alex_joni> well.. I learned to do that oo :D
[20:33:37] <alex_joni> s/oo/too/
[20:33:58] <alex_joni> especially when playing with 2 x 3-400A
[20:34:17] <BigJohnT> thats some amps there
[20:34:42] <alex_joni> yeah, it has the advantage no-one needs to hold that torch
[20:34:49] <alex_joni> and the robots don't complain .. much
[20:35:02] <BigJohnT> when they do you fix them :)
[20:35:49] <alex_joni> I got a 4" adjustable wrench
[20:36:50] <alex_joni> roughly 1.5m long and 20 pounds heavy.. when I turn up with that, no robots dare to complain anymore :D
[20:37:04] <anonimasu> lol
[20:37:14] <BigJohnT> that's a big one
[20:37:32] <BigJohnT> I have a 48" pipe wrench if you need help
[20:37:45] <alex_joni> a bit smaller than this one: http://www.robotmonkeylab.com/Monkeyshop/BigWrench/Props%20-%20Bigass%20wrench.jpg
[20:38:01] <anonimasu> alex_joni: is that you?
[20:38:02] <anonimasu> :p
[20:38:10] <anonimasu> if so, you damn very strong
[20:38:12] <anonimasu> (I know it's not)
[20:38:21] <alex_joni> anonimasu: it's a prop
[20:38:27] <anonimasu> I know ;)
[20:38:40] <alex_joni> the wrench is real though
[20:38:41] <alex_joni> lol
[20:39:00] <anonimasu> -_-
[20:39:01] <chr0n1c> i've seen open ended wrenches taller than me
[20:39:16] <anonimasu> well, when you need cranes to move them they are big.
[20:39:23] <alex_joni> the biggest tool I've seen was a 5m caliper :D
[20:39:33] <chr0n1c> 5 meters?
[20:39:37] <alex_joni> yes
[20:39:52] <chr0n1c> that's a big caliper...
[20:39:57] <alex_joni> wasn't very heavy..
[20:40:04] <alex_joni> 2 people could nicely work with it
[20:40:06] <chr0n1c> the biggest caliper i've used is 48"
[20:40:38] <anonimasu> hm, im buying that grinder.
[20:40:44] <anonimasu> if it's still there tomorrow
[20:43:51] <BigJohnT> alex_joni: so normalizing is for the heat affected zone only?
[20:44:33] <alex_joni> BigJohnT: no.. for releaving metals of stress
[20:44:56] <alex_joni> that internal stress might be from casting, welding, bending, whatnot
[20:45:29] <BigJohnT> for welding from the weld pulling as it cools?
[20:45:48] <alex_joni> that and the heat affected zone
[20:46:08] <alex_joni> actually the whole part starts to bend after welding
[20:46:23] <alex_joni> depending on the sheet thickness and weld geometry it's more or less visible
[20:46:42] <alex_joni> I welded some 1/2" sheets the other day
[20:46:47] <BigJohnT> yea, I've seen that a bunch
[20:46:50] <alex_joni> and used lots of current/small speed
[20:46:58] <alex_joni> it curved about 1" up :D
[20:47:21] <BigJohnT> try that on stainless and it will curve up 4"
[20:47:22] <alex_joni> the plates were roughly 2-3 feet long
[20:47:36] <alex_joni> I haven't seen much 1/2" stainless :D
[20:48:02] <BigJohnT> I do some stainless structural from time to time and it really moves
[20:48:19] <alex_joni> yeah.. I did welds on .5 - 1mm sheets of stainless
[20:48:24] <alex_joni> there it's extreme..
[20:48:49] <BigJohnT> a T joint will warp the heck out of the tube
[20:49:04] <alex_joni> I also welded some 100mm sheets :D
[20:49:24] <alex_joni> 4-5" sheets
[20:49:36] <BigJohnT> wide?
[20:49:40] <alex_joni> thickness
[20:49:51] <BigJohnT> wow
[20:50:01] <alex_joni> yeah, hard to call it a sheet :D
[20:50:15] <alex_joni> but if it comes in a 2x12m size
[20:51:24] <alex_joni> that reminds me ..
[20:51:29] <alex_joni> I saw a nice application lately
[20:51:38] <BigJohnT> what's that?
[20:51:43] <alex_joni> they use metal sheets to make some beams
[20:51:51] <alex_joni> but the sheets come in rolls, not flat
[20:51:56] <alex_joni> and it's 1" thick
[20:52:05] <fenn> how many amps do you need to weld 100mm?
[20:52:16] <alex_joni> fenn: not more than for 20mm
[20:52:25] <fenn> uh.. how much is that
[20:52:26] <alex_joni> you just need more passes and a wider weld area
[20:52:33] <alex_joni> 3-400A for manual welding
[20:53:01] <alex_joni> you can probably weld it with 200A and a lot of time and passes too..
[20:53:24] <alex_joni> BigJohnT: so.. long rolls of 1" thick metal
[20:53:35] <alex_joni> goes through some machine to straighten it out
[20:53:47] <BigJohnT> I know how that works :)
[20:53:56] <alex_joni> then through another that cuts it (mechanically) into stripes (I think 10 pcs at once)
[20:54:16] <BigJohnT> that's some big iron doing that
[20:54:22] <fenn> why dont they just do that at the mill?
[20:54:26] <alex_joni> BigJohnT: yeah, I've seen it done a lot of times.. but not in 1" thick.. that was really sick :)
[20:54:36] <alex_joni> fenn: steel mill?
[20:54:39] <fenn> yes
[20:54:48] <alex_joni> that's couple k km away
[20:55:09] <fenn> how long are the beams?
[20:55:15] <alex_joni> and you seldom have the same widths you need
[20:55:21] <alex_joni> fenn: sometimes up to 18-19m
[20:55:45] <alex_joni> but usually up to 8-9 m
[20:56:22] <BigJohnT> in Tiawan I went to a window blind company that made the slats from roll stock. They had a 20' deep pit after the slitter because the different thickness across the roll would wind up at different speeds
[20:57:41] <BigJohnT> bbl
[21:01:27] <chr0n1c> i can delete stepper.var and emc will re-make it on startup?
[21:02:07] <chr0n1c> or uh... can i?
[21:02:43] <chr0n1c> i think my g5X's went screwy somewhere
[21:03:37] <alex_joni> chr0n1c: nope
[21:03:50] <alex_joni> but you can copy another one from /etc/emc2/sample-configs/stepper
[21:04:01] <chr0n1c> oh, so what happens if i set everything to 0.00000 like i just did?
[21:04:17] <chr0n1c> it seems to corrected my strange behavior
[21:05:27] <chr0n1c> hmm... is there a something somewhere that would tell me what all the var's in that file are?
[21:07:24] <chr0n1c> one changed back to a 1.00000 after i loaded emc2 from 0.00000
[21:07:36] <alex_joni> chr0n1c: yup.. it's called a manual :)
[21:07:54] <alex_joni> the one with 1.000 describes the currently used coordinate system
[21:08:26] <chr0n1c> ahh, i usually don't read manuals until i get stuck...
[21:09:06] <chr0n1c> i have read quite a bit of the emc manuls at this point ;)
[21:09:15] <chr0n1c> but not that part
[21:12:19] <alex_joni> that's the best part
[21:12:28] <alex_joni> I always sleep so well when I try to read it :D
[21:12:35] <BigJohnT> chr0n1c: take a look at G92 in the manual
[21:13:30] <chr0n1c> g92x0y0z0 ?
[21:13:48] <BigJohnT> G92.1
[21:14:14] <chr0n1c> ahh one line down ;)
[21:14:17] <chr0n1c> ty
[21:18:44] <alex_joni> good night all
[21:18:50] <jmkasunich> night alex
[21:18:55] <BigJohnT> good night alex
[21:20:07] <chr0n1c> later alex...
[21:20:08] <dmess> g92 is a deadly SIN...
[21:20:41] <chr0n1c> here goes the ink and paper verify of the midibox_core module...
[21:20:59] <chr0n1c> i'll let 'all know how it turns out in a couple hours.. lol
[21:31:02] <chr0n1c> so, the ink cartridge from inside the ink pen fits in my spindle collet... shoulda tried that a long time ago