#linuxcnc | Logs for 2013-01-04

[01:34:01] <RyanS> is half-stepping okay for driving a leadscrew? I'm not that concerned about the resolution
[01:35:14] <archivist> I use half step
[01:47:57] <RyanS> so 1/16, 1/32 is more for higher resolution and accuracy?
[01:48:39] <archivist> not accuracy that can be snake oil, it can reduce resonance though
[01:49:25] <archivist> http://www.micromo.com/microstepping-myths-and-realities.aspx
[02:13:27] <DJ9DJ> moin
[02:15:56] <RyanS> so rather than the rotor being held in say step 100 with full step, half-stepping would have the rotor 'balanced' between 100-101 so you lose some holding torque ?
[02:17:41] <t12> and it likely isnt quite balanced in half
[02:17:49] <t12> as a per-motor characteristic
[02:17:58] <t12> thats how i interpert it at least?
[02:18:34] <t12> i found some microscope stage motor controllers
[02:18:41] <t12> that are 1/64 and 1/128 steps i think
[02:20:15] <RyanS> hmmn this article seems to suggest that 'detent torque' is bad but I would have thought it would increase the holding torque
[02:27:41] <archivist> steppers are simple to get going but you need to give them some headroom, use a more powerful motor than the measured torque of your lead screw
[02:28:38] <archivist> dont attempt to run at maximum acceleration or speed else you leave nothing spare to drive the load
[02:31:18] <archivist> when testing I put a large amount of weight on the table to find the maximums for my machine and set slower values for running
[02:31:35] <archivist> even then I later had to lower some more
[04:45:00] <Loetmichel> re at home... i think i am getting old... 20 hrs ago i drove to my sister, some 200km away... changed the hardware on her PC... and fixed the windows on 3 of her employers Notebooks... drove back just now... and had to have half an hour nap half way because my eyes wouldnt stay open... no stamina left :-(
[04:47:06] <archivist> aw
[04:48:46] <Loetmichel> ... 20 years ago i would have laughed about 30 hrs awake and 20 hrs "work"... and now i am SO short of napping away :-(
[04:49:07] <mrsun> 20 hours for 200km ? :P
[04:49:20] <mrsun> yeah you must be getting old ...
[04:49:24] <mrsun> 10km/h
[04:49:54] <archivist> he drives faster, just slow at fixing windows
[04:50:00] * archivist ducks
[04:50:07] <Loetmichel> mrsun: 2 hrs drive. and in between 4 computers to fix. soft and hardware
[04:50:09] <mrsun> ahh
[04:50:12] <mrsun> 20 hours AGO
[04:50:18] <Loetmichel> right
[04:50:19] <mrsun> i just keep reading stuff wrong these days :P
[04:50:25] <mrsun> i must be getting old :P
[04:50:55] <Loetmichel> hrhr
[08:01:11] <r00t4rd3d> http://techcrunch.com/2013/01/03/kickstarter-leikr-is-an-openstreetmap-gps-sports-watch-with-a-two-inch-colour-screen/
[09:23:57] <DJ9DJ> re
[09:34:22] <ReadError> hello
[09:34:32] <ReadError> so im testing something within parallels on linuxcnc
[09:34:41] <ReadError> i downloaded the simulator version
[09:34:49] <ReadError> but its *still* looking for a parport
[09:36:39] <JT-Shop> the pure simulator for LinuxCNC?
[09:40:12] <JT-Shop> http://www.youtube.com/watch_popup?v=tPg1ZMiC9pA
[09:44:29] <ReadError> yea
[09:44:52] <archivist> I remember that from a while ago :)
[09:56:22] <ReadError> ahh fixed that error
[09:56:32] <ReadError> now i have the issue with libc segfaulting
[10:19:43] * JT-Shop has never used the pure simulator
[10:46:17] <skunkworks> JT-Shop, any luck with your touch screen?
[10:54:05] <ReadError> ok so
[10:54:14] <ReadError> it turns out, parallels tools is breaking linuxcnc im sim mode
[10:55:05] <archivist> us engineers in here think parallels are made of metal
[10:55:20] <ReadError> "Parallels Desktop"
[10:56:38] <archivist> the real thing TM http://www.archivist.info/cnc/stage6/P1010033_t.jpg
[11:26:14] <halo_cast> hello all
[11:28:28] <JT-Shop> hi
[11:34:18] <halo_cast> I am thinking to realize a plasma cutter using linux cnc as software. I learned that for plasma cutters the distance between torch and steel is very important. It might be that the steel plate is not completely flat so keeping the Z axis constant could be a bad choice. I thought of a solution: Using a contact switch instead the torch in a first run one could measure a grid of Z heights of the steel plate by moving
[11:34:18] <halo_cast> from position to position going down the z axis until the contact is made. Then, in a second run this info could be used to control the torch distance over the steel plate. The question is: Is linux CNC capable to do this? Is this function implemented?
[11:35:08] <JT-Shop> that is a probe move, but the plate will move as you cut if thin so a THC is needed
[11:35:45] <JT-Shop> LinucCNC works well with the Mesa THCAD card... add a floating head with a probe switch and your good to go
[11:35:50] <JT-Shop> need some photos?
[11:36:17] <halo_cast> yes please
[11:36:24] <JT-Shop> http://www.gnipsel.com/shop/plasma/plasma.xhtml
[11:36:44] <halo_cast> This page is under construction at the moment.
[11:38:01] <halo_cast> So I understand it is implemented but can cause problems?
[11:40:02] <halo_cast> JT-Shop: it Says "this page is under construction"
[11:40:37] <archivist> see buttons to left
[11:41:24] <archivist> unfortunate heading to that page some wont go past a construction sign
[11:43:04] <halo_cast> ok
[11:43:10] <JT-Shop> just the page not the info
[11:43:13] <halo_cast> is it "plasma gallery?"
[11:43:26] * JT-Shop just put the last part in the mill till lunch
[11:43:31] <JT-Shop> yes
[11:45:07] <halo_cast> most of the pics are not shown - which one do u mean?
[11:45:57] <JT-Shop> just look at them all
[11:46:23] <JT-Shop> more here http://s47.beta.photobucket.com/user/johnplctech/library/Plasma%20Cutter
[11:46:29] <JT-Shop> bbl
[11:47:46] <halo_cast> nice machinery
[11:47:47] <IchGuckLive> hi all
[11:47:57] <DJ9DJ> hi there
[11:53:11] <halo_cast> Is there anybody else who has done a plasma CNC?
[11:53:56] <cncbasher> yes .. best advice THC and a floating head as JT has described
[11:54:41] <IchGuckLive> halo_cast: most of us are doning this now as the prise of the powerfax are falling
[11:55:07] <halo_cast> Powerfax?
[11:56:07] <IchGuckLive> hypertherm powermax xxx
[11:56:24] <IchGuckLive> where are you from country
[11:56:28] <IchGuckLive> USA Europ
[11:57:48] <halo_cast> Europe, Germany
[11:58:12] <IchGuckLive> Dann bist du hier richtig ich sitze in Ramstein RLP
[11:58:15] <halo_cast> I have a Lorch 7020 Plasma cutter - Bought it at Ebay as broken and restored it.
[12:01:17] <halo_cast> http://picpaste.com/Plasma_Lorch_7020-CuwEt6ex.jpg
[12:10:42] <t12> what was broken?
[12:30:03] <halo_cast> t12: With my plasma?
[12:30:26] <t12> ya
[12:39:59] <halo_cast> t12: rectifier, Pressure reducer, contactors, torch, air hoses - and not to forget the idiot who "repaired" the mashine before me.
[12:46:21] <halo_cast> t12?
[12:58:34] <t12> ahh
[12:58:41] <t12> was it worth the repair hassle
[12:58:53] <t12> vs n ew or used/working?
[13:02:10] <FinboySlick> andypugh: Mind if I pick your material scientist brain for a moment?
[13:02:37] <andypugh> Go on
[13:04:27] <FinboySlick> andypugh: I'm obsessing over the Stirling cycle engine as I do every few months and I was wondering... Since PV = nRT, an ideal gas for stirling would be H2 since you can get a lot more n for a given V at a given T differential. But H2 leaks through everything.
[13:05:32] <FinboySlick> So I started pondering anodizing the inside of the container to optimize on the smallest gas molecule.
[13:05:45] <andypugh> Why do you think that you get more V for the same n? Ideal gasses all have the same molar volume (24 litres IIRC)
[13:06:00] <FinboySlick> I get more n for a given V.
[13:06:08] <FinboySlick> not more v for a given n.
[13:06:12] <andypugh> n = number of molecules.
[13:07:09] <FinboySlick> Well, I was thinking that the smaller they are, the more you can fit in a given volume (and pressure and temperature).
[13:07:25] <andypugh> I am pretty sure that isn't the case.
[13:07:46] <andypugh> http://en.wikipedia.org/wiki/Molar_volume
[13:08:13] <FinboySlick> Darn, and here I thought that this was the reason why hydrogen based stirlings were supposedly better.
[13:08:13] <andypugh> Though that is admittedly an "ideal gas" and I don't know how far from ideal real gasses are.
[13:08:42] <andypugh> Well, the specific heat of a given volume of hydrogen may be much lower.
[13:09:50] <FinboySlick> So the key here would be to optimize on specific heat with a lower limit on molecule size?
[13:10:10] <andypugh> Possibly. Argon looks good in that case.
[13:11:42] <FinboySlick> I've been toying with a 100% sealed design (no side of pistons exposed to atmosphere). But I'm not sure what to fill it with yet ;)
[13:12:50] <guest_______> Hi, running my first real program - getting an error when I load my code - Do I need to predefine the home position? g28.1? can I do this in mdi? will the g28.1 values remain in the contol after shutdown?
[13:13:10] <guest_______> Hi, running my first real program - getting an error when I load my code - Do I need to predefine the home position? g28.1? can I do this in mdi? will the g28.1 values remain in the contol after shutdown?paul
[13:13:25] <FinboySlick> guest_______: Who's paul? ;)
[13:14:01] <guest_______> New guy!
[13:14:17] <guest_______> Vancouver Island
[13:14:24] <FinboySlick> Yay Canada!
[13:14:37] <FinboySlick> I'm at the other end.
[13:14:53] <guest_______> Maritimes?
[13:15:15] <FinboySlick> Well, the bit of quebec that invades the Maritimes, yeah. Gaspe penninsula.
[13:16:28] <archivist> FinboySlick, seen http://www.stirlingengines.org.uk/ ?
[13:16:29] <IchGuckLive> guest_______: are there Homeswiches on the joints
[13:16:46] <guest_______> yes, I can home
[13:16:48] <IchGuckLive> or do you rubn without homing
[13:16:59] <FinboySlick> archivist: That guy looks way too serious.
[13:17:35] <IchGuckLive> guest_______: http://www.linuxcnc.org/docs/2.4/html/gcode_main.html#sub:G28,-G30:-Return
[13:18:00] <archivist> FinboySlick, there have been some well made examples in the competitions over here
[13:19:56] <guest_______> Yes, I have read that, but can I put the values in with mdi? Once in, do they remain until changed?
[13:20:24] <IchGuckLive> yes
[13:20:32] <FinboySlick> guest_______: You can execute single lines of gcode in axis to set these. I'm not sure if they are permanent.
[13:21:48] <guest_______> ok, thanks guys - off to the shop!
[13:22:26] <archivist> run a network cable to the shop
[13:22:37] <guest_______> Didn't Springsteen have a hit Born in the Gaspe?
[13:23:39] <FinboySlick> guest_______: Heh, maybe but I don't think his first name was Bruce in this case.
[13:43:59] <JT-Shop> dgarr: you around?
[13:52:57] <DJ9DJ> gn8
[13:57:51] <cncbasher> fantastic
[14:46:24] <JT-Shop> damn tool changer broke on the last part... time for a break
[14:46:53] <pfred1> I broke last week
[14:48:02] <pfred1> doc gave me a bottle of hillbilly heroin and told me no strenious activities until further notice
[14:48:38] <AR_> i got 2 linear rails with bearings and a 6x8" aluminum plate
[14:48:41] <AR_> good enough
[14:50:26] <AR_> 2 ballsecrews i ordered off of ebay with a very vague description for $25 should be arriving today
[14:50:34] <AR_> interested to see what I actually purchased
[14:51:24] <ravenlock> could anyone explain to me *why* a machine would use a "feed rate" which is of the form ((maxDesiredRate)/(lengthOfSegment))^-1 per minute?
[14:52:01] <ravenlock> it seems the effect is "shorter segments feed slower". maybe that is the point of it?
[14:52:20] <pfred1> sounds legit
[14:52:37] <ravenlock> to "put the brakes on a bit" ?
[14:52:43] <archivist> you should read the trajectory planner page on the wiki
[14:53:09] <archivist> depends on forward planning
[14:53:29] <pfred1> I had plans they're all on hold now
[14:54:01] <ravenlock> archivist, referring to my query?
[14:54:05] <ravenlock> do you have a url?
[14:54:05] <archivist> yes
[14:55:15] <archivist> start here http://wiki.linuxcnc.org/cgi-bin/wiki.pl?TrajectoryControl and there are some other pages
[14:55:27] <ravenlock> cool thanks
[14:56:11] <archivist> link to hairy maffs at bottom
[14:56:21] <ravenlock> niiice
[14:56:34] <archivist> and pretty graphs
[14:57:00] <paul___> ok, I am back - I think I have my g28.1 loaded in the control - still getting this error - near line 20 - cannot use axis values without a gcode that uses them. -
[14:57:09] <paul___> % (SPOT DRILL) (T2 D=0.25 CR=0. TAPER=90DEG - ZMIN=-0.05 - SPOT DRILL) N10 G90 G94 G17 N15 G20 N20 G28 G91 Z0. N25 G90 (SPOT DRILL) N30 M9 N35 T2 M6 N40 S1679 M3 N45 G54 N50 M8 N55 G0 X0.5386 Y-0.54 N60 G43 Z0.6 H2 N65 G17 N70 G0 Z0.2 N75 G98 G82 X0.5386 Y-0.54 Z-0.05 R0.2 P0.1 F2.5 N80 X1.5386 N85 G80 N90 Z0.6 N100 M9 N105 G28 G91 Z0. N110 G28 X0. Y0. N115 M30 %
[14:59:26] <paul___> ooh that didn't format too well.
[15:00:41] <paul___> % (SPOT DRILL) (T2 D=0.25 CR=0. TAPER=90DEG - ZMIN=-0.05 - SPOT DRILL) N10 G90 G94 G17 N15 G20 N20 G28 G91 Z0. N25 G90 (SPOT DRILL) N30 M9 N35 T2 M6 N40 S1679 M3 N45 G54 N50 M8 N55 G0 X0.5386 Y-0.54 N60 G43 Z0.6 H2 N65 G17 N70 G0 Z0.2 N75 G98 G82 X0.5386 Y-0.54 Z-0.05 R0.2 P0.1 F2.5 N80 X1.5386 N85 G80 N90 Z0.6 N100 M9 N105 G28 G91 Z0. N110 G28 X0. Y0. N115 M30 %
[15:00:46] <archivist> use a pastebin we cannot see where line 20 is
[15:01:12] <tjb1> holy spam
[15:02:15] <tjb1> JT-Shop: Stop breaking things
[15:02:18] <paul___> Oh, I don't know what a paste bin is, tried to become a forum member, but gave up after multiple attempts at registering.
[15:03:14] <archivist> forum spam filter seems borked we get a few moans
[15:03:40] <ravenlock> paul___, pastebin.com
[15:06:52] <paul___> ok, bear with me...
[15:07:24] <pfred1> I reserve my right to keep armed bears!
[15:07:42] <paul___> http://pastebin.com/kWWuWssb
[15:07:46] <paul___> ok?
[15:10:09] <archivist> what is line 21 doing
[15:10:10] <cradek> paul___: following G80 by Z0.6 is an error
[15:10:51] <cradek> perhaps you mean G0 Z0.6 or G1 Z0.6?
[15:11:07] <cradek> http://www.linuxcnc.org/docs/html/gcode/gcode.html#sec:G80-Cancel-Modal
[15:13:38] <cradek> also, bookmark this right now: http://www.linuxcnc.org/docs/html/gcode.html
[15:13:48] <pfred1> hey cradek!
[15:14:11] <cradek> uh-oh
[15:14:34] <pfred1> what? all I said was hello
[15:14:44] <cradek> ah, hi!
[15:14:54] <pfred1> I'm out of commission
[15:16:09] <cradek> howso?
[15:16:34] <pfred1> this time last week something in my groin let go which lead to me having to have mergency surgery
[15:16:49] <pfred1> yup was just about now
[15:17:08] <cradek> well that sure sounds bad
[15:17:13] <pfred1> minutes fro mthat feteful event
[15:17:14] <cradek> hope you're back together soon
[15:17:31] <pfred1> thanks yeah I hope to recover someday too
[15:19:10] <pfred1> so far it has been a lesson in humility
[15:19:19] <paul___> thanks, cradek, I will look at those links
[15:20:28] <paul___> so I need a motion code after the g80?
[15:20:43] <cradek> yes, that's what the docs are trying to say
[15:20:48] <cradek> it could be clearer
[15:20:58] * pfred1 needs some motion code for ah you know where ...
[15:21:03] <cradek> but G80 cancels all motion codes, that's its only purpose
[15:21:15] <paul___> this was a post from a cam program
[15:21:18] <pfred1> is that what happened to me?
[15:25:45] <paul___> thank for your help, I will add a g0 and retry
[15:26:48] <cradek> welcome
[15:59:54] <andypugh> Darn! I was going to ask Paul___ what his forum name was.
[16:03:34] * pfred1 's first name is Paul
[16:04:05] <pfred1> that is what the p stands for
[16:04:15] <andypugh> ravenlock: That equation looks rather a lot like inverse time feed rate.
[16:05:18] <andypugh> It is a feed rate mode where you say how long the move should take, rather than how fast it should move. Except it is (for unknown reasons) inverse time, so bigger nulbers are faster.
[16:07:35] <sc__> hello
[16:07:53] <pfred1> hi
[16:08:38] <sc__> well I'm looking for some help ...
[16:08:49] <dr00bie> what linux capable cam software are people using with linuxcnc?
[16:09:14] <ravenlock> andypugh, it is, yes
[16:09:34] <ravenlock> what is the purpose of that exactly (was my question).
[16:09:41] <ravenlock> why not just "feed rate" ?
[16:09:51] <ravenlock> why make it complicated?
[16:10:03] <cradek> for some complicated moves, it's hard to say what the feed rate is. think of a 5 axis machine doing a complex curve.
[16:10:26] <andypugh> I think it is useful for coordinated moves with angular axes included. It is only really usable by CAM systems (every move needs a fedrate) but a CAM system may know the radius of rotation, whereas G-code doesn't
[16:10:47] <andypugh> sc__: Ask the question, don't ask to ask.. :-)
[16:11:16] <andypugh> ravenlock: It's just one of the options, normally.
[16:11:38] <ravenlock> yeah, but I was "told to use it". basically by the machine mfgr
[16:11:54] <pfred1> sc__ also don't forget to visit the nice forum at http://www.linuxcnc.org/index.php/english/forum/index
[16:12:03] <ravenlock> and, so let me ask another....
[16:12:38] <andypugh> sc__: Ask here first, the forum doesn't have as many folks on it as the IRC.
[16:12:44] <ravenlock> should the "distance in question" be that of the "current LINE segment", or that of the "entire stroke" ?
[16:12:47] <pfred1> liez!
[16:12:48] <sc__> I'm getting the RTAI[hal]: ERROR, LOCAL APIC CONFIGURED BUT NOT AVAILABLE/ENABLED. tried enabling lapic in grub but still the same error does anyone know somehing else I can try?
[16:12:50] <ravenlock> I never use the forums
[16:13:16] <ravenlock> IRC ftw
[16:13:19] <cradek> sc__: did you check your bios for things that look relevant?
[16:13:35] <cradek> sometimes there are some apic-related options in there.
[16:13:41] <pfred1> I think more people are active on the forum
[16:13:48] <sc__> yes but I have no setting related to APIC
[16:13:49] <ravenlock> ant by "stroke" I refer to , position the tool, enter material, navigate, exit material
[16:15:19] <andypugh> sc__: You might be out of luck with that PC, I am afraid.
[16:15:42] <sc__> :(
[16:15:53] <sc__> It's a laptop
[16:16:10] <pfred1> laptops are oftne not good CNC candidates
[16:16:11] <cradek> it probably wouldn't work acceptably for controlling a real machine anyway, then
[16:16:18] <pfred1> often even
[16:16:42] <sc__> yes I know but I thought it's worth a try
[16:16:47] <sc__> mach3 did work
[16:16:53] <pfred1> sure can't hurt
[16:17:28] <sc__> But since I'ts no real time os I thought I'd try EMC2
[16:18:00] <pfred1> mach3 takes a more invasive approach as I understand it to work
[16:18:06] <dr00bie> sc__: hardware specs?
[16:18:54] <pfred1> mach3 functions more like a zombie virus than anything else
[16:19:02] <sc__> pentium3 256 mb ram
[16:19:19] <pfred1> I run EMC2 on a P3
[16:19:23] <pfred1> but it is a tower
[16:19:31] <sc__> mmh
[16:19:31] <dr00bie> pfred1: any reason why laptops don't make good cnc candidates?
[16:19:33] <cradek> that might be old enough to actually work. try our old hardy-based install
[16:19:59] <pfred1> dr00bie a few mostly laptops have more housekeeping than desktops
[16:20:06] <cradek> dr00bie: their power-saving features, probably
[16:20:17] <pfred1> that housekeeping translates into latency issues
[16:20:44] <sc__> what dod you mean with old hardy based setup?
[16:21:19] <pfred1> plus laptop parallel ports are notoriously underpowered
[16:21:19] <dr00bie> pfred1: interesting... I have seen more repraps running off of laptops than desktops..
[16:21:31] <pfred1> reprap is java code
[16:21:43] <cradek> don't those have microcontroller-based motion?
[16:21:56] <pfred1> nah well maybe they could
[16:21:57] <dr00bie> cradek: you are right... my bad...
[16:22:02] <dr00bie> arduinos
[16:22:07] <dr00bie> i'm a dummy ;)
[16:22:08] <andypugh> sc__: Try this link http://www.linuxcnc.org/iso/ubuntu-8.04-desktop-emc2-aj13-i386.iso
[16:22:48] <sc__> I've tried using arduino but it's too slow a G3 command takes a few millisecs to compute
[16:22:54] <andypugh> It's an older version of Ubuntu, with a kernel that only supports single-core CPUs, which means it doesn't need the APIC.
[16:22:59] <pfred1> cradek I think the reprap performance is orders of magnitude less than acceptable LinuxCNC
[16:23:03] <dr00bie> pfred1: my reprap laptop doesn't have parallel, so that is why I haven't tried running my cheapo TB6560s with it...
[16:23:29] <sc__> thanks andy
[16:23:41] <dr00bie> pfred1: you are right there...
[16:24:09] <pfred1> dr00bie I am the Gawd of the TB6560AHQ BTW
[16:24:12] <andypugh> sc__: You should still be able to run the very latest version of LinuxCNC, just don't update the Ubuntu version.
[16:24:45] <sc__> I see thanks a lot
[16:24:49] <pfred1> dr00bie https://www.youtube.com/watch?v=GU2GaSMPxNI
[16:26:20] <pfred1> I never understood what the deal was with people saying not to update
[16:26:39] <pfred1> is that because the kernel might be made not the default or something?
[16:26:48] <andypugh> Updates tend to install a new kernel. That tends to break the LinuxCNC installation.
[16:27:02] <pfred1> yeah but it shouldn't uninstall an old kernel
[16:27:16] <pfred1> that isn't how dpkg works
[16:27:31] <pfred1> it just gets pushed down the menu
[16:27:54] <cradek> the update manager is not particularly clear about what you're getting
[16:27:57] <andypugh> Can you guarantee that any given OS version is completely kernel-agnostic?
[16:28:04] <cradek> OS version update vs package updates
[16:28:17] <pfred1> oh wull upgrade is different
[16:28:20] <pfred1> full even
[16:28:30] <dr00bie> pfred1: nice! my soldering skills are decent, but my electronics knowledge is very slim atm, so I just usually get kits. The TB6560 controller I have is from ebay and I bought it several years ago and never got around to the project.
[16:28:34] <pfred1> full upgrade can and will break all kinds of things
[16:28:47] <andypugh> Ah, sorry, I read "Update" as "Upgrade". You ought to Update yes.
[16:28:59] <dr00bie> pfred1: from what I understand, the TB6560s are considered trash by most diy cnc users...
[16:29:13] <pfred1> dr00bie I built my drivers before the chinese boards were available
[16:29:18] <andypugh> They are perfectly adequate, if a tad fragile.
[16:29:33] <pfred1> dr00bie most DIYers don't know much about electronics either
[16:29:54] <skunkworks> pfred1, building your own stepper drives?
[16:30:00] <skunkworks> what are they based on?
[16:30:01] <pfred1> so I hold their opinions in low regard
[16:30:40] <pfred1> skunkworks I built them a long time ago I've made some with TB6560 and others with SLA7026
[16:31:08] <skunkworks> neat.
[16:31:08] * pfred1 is bi and uni :)
[16:31:36] <pfred1> I want to get ahold of Toshiba's new drive ICs
[16:32:05] <skunkworks> I goofed around making my own about 10-15 years ago. At the time - microstepping wasn't easy for the diyer - gave up and found anything commercial worked quite well
[16:34:03] <pfred1> turns out even half stepping does the trick
[16:34:21] <pfred1> I made my own step sequencer for the SLA7026
[16:34:40] <andypugh> LinuxCNC supports a number of step sequences too.
[16:35:08] <pfred1> skunkworks http://img19.imageshack.us/img19/9769/hs2y.png
[16:35:27] <andypugh> And the eventual solution to my undesized-arbor problem was: https://picasaweb.google.com/lh/photo/vj6jrLOoldVzDo8qLqt34tMTjNZETYmyPJy0liipFm0?feat=directlink .... ie make a new one from scratch.
[16:36:48] <pfred1> http://img338.imageshack.us/img338/1538/pict0783o.jpg
[16:36:49] <skunkworks> andypugh, you have to make a video of that hobbing hobbing...
[16:36:53] <MercuryRising> how do you clear a g54? my machine origin and relative origin are offset, and want them to be the same again
[16:37:28] <andypugh> G10 L2(?) P1 X0 Y0 Z0
[16:37:46] <andypugh> Not sure about the L2 part
[16:37:55] <PCW> Andy you might mention on the BLDC manual that these:
[16:37:56] <PCW> 15,17,25,34 = forward
[16:37:58] <PCW> 13,22,30,32 = reverse
[16:38:00] <PCW> are the only pure gray code BLD hall sequences
[16:38:07] <skunkworks> MercuryRising, good reading..... and your part http://wiki.linuxcnc.org/cgi-bin/wiki.pl?CoordinateSystems#So_if_you_re_lost_what_should_you_do
[16:38:08] <pfred1> andypugh you lathed that arbor?
[16:38:16] <andypugh> pfred1: Yes
[16:38:22] <MercuryRising> awesome, thanks!
[16:38:23] <pfred1> andypugh looks really nice
[16:38:50] <skunkworks> andypugh, nice having cnc for the taper? ;)
[16:39:10] <andypugh> Yes, it makes tapers really easy, and they fit perfectly first time too.
[16:39:18] <skunkworks> right :)
[16:39:42] <pfred1> I made a taper by hand once it didn't work the first time around
[16:40:06] <skunkworks> we have a taper attachemnt for the monarch - but it is still a pain to use.
[16:40:14] <pfred1> worked after I hit it with some valve grinding compound though
[16:41:14] <skunkworks> andypugh, what is the gear for?
[16:41:29] <pfred1> steampunk!
[16:42:02] <andypugh> I had to make a socket to hold the taper at the chuck-end, but that was also easy with the CNC. I actually made a socket that screws on to the spindle nose. Another thing CNC makes easy is internal threads in blind holes. :-)
[16:42:30] * skunkworks needs to get his lathe running
[16:42:35] <skunkworks> *cnc lathe
[16:42:38] <andypugh> skunkworks: That hob is for making timing pulleys. My X-axis drive is going to need a rather wierd pulley
[16:42:54] <skunkworks> andypugh, ah - cool
[16:43:06] <andypugh> (I might offer a blank-hobbing service if it works out well)
[16:43:43] <skunkworks> again - video!
[16:44:06] <pfred1> andypugh admit it these are your friends http://hopeliesat24framespersecond.files.wordpress.com/2011/07/costumes.jpg
[16:44:19] <andypugh> Tomorrows job will be to see if the servo I have is butch enough to operate the rotary.
[16:44:34] <jpratt3000> hi everyone - hope you all had a great start to the New Year!
[16:44:57] <andypugh> pfred1: The one in the middle is more than welcome to be.
[16:45:39] <jpratt3000> i've got a total n00b question - i just put a ruler down to check my accuracy and its off by quite a bit. what is the formula for setting length of travel on a linear axis?
[16:45:55] <pfred1> andypugh well you show some steampunk babes some of your brass gears and you're in!
[16:46:19] <andypugh> I am not entirely sure that I _don't_ know any of those folk, actually.
[16:46:31] <andypugh> Any idea where the photo was taken?
[16:46:45] <pfred1> http://hopelies.com/2011/08/03/steampunk-where-are-the-films/
[16:46:48] <pfred1> page it is from
[16:47:16] <ds3> are there any good pages on characterizing missing steps on a stepper system?
[16:47:17] <pfred1> I read the book I have to admit I still don't fully understand the movement
[16:47:43] <pfred1> I actually read the book before there was a movement
[16:48:24] <pfred1> missing steps usually means you're trying to run too fast
[16:48:39] <pfred1> although it could be caused by noise in your system too
[16:49:04] <andypugh> pfred1: : Sounds like the photo was as ComicCon. I haven't been to that.
[16:49:31] <pfred1> andypugh people you know could have attended though
[16:49:41] <andypugh> I got into CNC because I wanted to make a steampunk clock..
[16:49:59] <pfred1> but have you read The Difference Engine?
[16:50:18] <andypugh> Yes, and in fact my clock is difference-engine inspired.
[16:50:26] <pfred1> that I believe is what started it all
[16:51:44] <pfred1> andypugh see I knew there was a steampunk tie in with you and the brass gears
[16:52:15] <pfred1> people etch gears with good effect
[16:52:27] <pfred1> you know just for the look
[16:53:43] <ReadError> so i ordered some cheap endmills on ebay
[16:53:47] <ReadError> got a really nice holder!
[16:53:50] <ReadError> holds about 100
[16:53:50] <pfred1> ought oh
[16:54:18] <ReadError> http://www.ebay.com/itm/10-1-8-1250-2-FLUTE-CARBIDE-ENDMILLS-NEW-/150964627802?pt=LH_DefaultDomain_0&hash=item232631695a
[16:54:25] <ReadError> came with a plastic thing that red tray goes in
[16:54:38] <pfred1> 2 flute huh?
[16:54:50] <pfred1> they're good for soft materials
[16:55:10] <pfred1> not so good for steel
[16:55:28] <ReadError> nah i dont cut steel really
[16:55:34] <ReadError> just aluminum/cf/g10
[16:55:36] <pfred1> OK then you're set
[16:55:45] <ReadError> i think a 3flute would be better for the g10/cf
[16:55:49] <ReadError> but 2f works alright
[16:55:49] <pfred1> yeah 2 flute nice on aluminum
[16:56:41] <pfred1> carbide is still so brittle though I prefer HSS
[16:57:53] <pfred1> I always manage to snap an endmill long before I dull it out
[16:58:29] <pfred1> although if you dull an endmill out they snap anyways that is how they die
[16:58:52] <pfred1> they just don't cut well enough to relieve the side load on them eventually
[16:59:16] <pfred1> I call it coughing up sand when they do it
[16:59:47] <pfred1> because they don't make large chips anymore they make swarf that looks like sand
[17:00:39] <pfred1> when I worked in a machine shop we ran bits on production jobs until they snapped
[17:01:06] <pfred1> wasn't worth resharpening them
[17:01:27] <ReadError> i would probably end up making it more dull trying to sharpen it ;)
[17:01:36] <ReadError> wouldnt the dimensions of it change after removing material ?
[17:01:40] <pfred1> you'd get maybe 20 more pieces while it coughed up sand
[17:01:49] <pfred1> yes
[17:02:02] <ReadError> i need to get some HSS stock
[17:02:06] <ReadError> for making lathe bits
[17:02:23] <pfred1> I have a big box of lathe blanks
[17:02:44] <ReadError> whats a good source?
[17:02:46] <pfred1> must be about 20 pounds
[17:02:50] <ReadError> jeeze
[17:03:04] <pfred1> I don't know I think my grandfather got them off a machinist he knew that died
[18:19:16] * JT-Shop got the tools out of the ATC and thinks he fingered a way to run the last part...
[18:26:40] <ReadError> dumb question
[18:26:47] <ReadError> if im doing manual tool changes
[18:26:58] <ReadError> can i re-touch off z axis?
[18:28:33] <cradek> only by stopping, touching off, then run from line after the tool change
[18:28:52] <cradek> axis keeps track of where in the program you aborted, so it's easy to find the restart point
[18:30:59] <ds3> no good guides on debugging missing steps on steppers?
[18:31:59] <ReadError> cradek: i was thinking about just making 2 separate gcode programs then with the same dimensions
[18:32:06] <ReadError> since it should preserve the same point when i load it
[18:32:24] <cradek> a program per tool is another easy way
[18:32:45] <cradek> manual tool changing kind of sucks no matter how you do it...
[18:33:04] <ReadError> yea, i need to holes, countersink, then profiling
[18:33:14] <ReadError> so thats 3 changes
[18:33:27] <cradek> sometimes for mass production it's easier to change the part than the tool
[18:33:34] <cradek> depends on your fixturing
[18:33:46] <ReadError> or i might be able to do the countersink first, and use the endmill for the holes as well
[18:33:46] <cradek> you can sometimes avoid many touch offs that way
[18:34:00] <ReadError> but i figured removing some material would help the countersink work better
[18:34:24] <cradek> 90 degree point drillmills can sometimes do both jobs
[18:35:15] <ReadError> so i need to create a support ticket with parallels desktop
[18:35:35] <ReadError> i was testing my 'pendant' (3d mouse) before i put it on the actual linuxcnc box
[18:35:44] <ReadError> when you install their tools it breaks linuxcnc
[18:35:51] <ReadError> segfaults on libc
[18:37:41] <andypugh> ds3: It's hard to tell when the steps are missed, but it is _probably_ overload at low speed as at high speed the motor tends to stall and not recover.
[18:38:31] <ReadError> i have high hopes for this 3dconnexion spacenavigator + hidcomp
[18:54:18] <andypugh> It looks like it mght be useful.
[18:54:33] <andypugh> I am almost tempted to see ig I can find one cheap.
[18:54:49] <ReadError> the 3d mouse?
[18:55:05] <ReadError> hidcomp is pretty neat
[18:55:10] <ReadError> you can tune the curve
[18:55:22] <ReadError> to have it not very responsive around the middle
[18:55:51] <andypugh> I was meaning the mouse. But mainly for using with Inventor rather than LinuxCNC
[18:56:20] <ReadError> yea its pretty sweet in solidworks
[19:10:13] <andypugh> I wonder what the latency is like on this? http://app.audiogon.com/listings/media-servers-core-audio-technology-kryptos-ultimate-media-server-a-cost-no-object-marvel-2012-12-10-computer-audio-91403
[19:11:42] <andypugh> Hi-Fi biffs seem to have cornered the market in talking bollocks: "Open Architecture 64-bit Music Server for Additional Versatility ... We offer a fully optimized and rebuilt windows 7 64-bit Operating System with upgrade options to windows 8 once licensing becomes available. Our open architecture promotes versatility and higher potential for sonic performance and customization. A Linux operating system just can't do wh
[19:11:42] <andypugh> we want, doesn't sound anywhere near as good, and lacks expandability. "
[19:12:21] <abetusk> anyone have experience converting gerber to gcode?
[19:15:50] <ReadError> ive used pcb-gcode for eagle
[19:15:53] <ReadError> thats about all
[19:16:03] <ReadError> worked pretty well
[19:17:19] <abetusk> I'm using a tool called pcb2gcode and I'm finding that the front conversion is localized to the lower right quadrent, the back conversion is localized to the lower left quadrent and the drill conversion is localized to the upper left quadrent...
[19:17:53] <abetusk> Is this "standard" gerber and pcb2gcode blindly following it or is this the tool doing something stupid, do you think?
[19:30:22] <andypugh> Sounds like something odd about coordinate origins.
[19:31:29] <abetusk> andypugh, I think this is the culprit: http://tech.groups.yahoo.com/group/kicad-users/message/10283
[19:32:48] <andypugh> Worth a try
[19:34:14] <ReadError> abetusk, ive heard good things about diptrace
[19:34:18] <ReadError> never used it myself though
[19:35:24] <abetusk> free version limited to 300 pins and non-commercial use. I'll stick with KiCAD
[19:35:28] <abetusk> thank you though
[19:36:16] <ReadError> are you a student ?
[19:40:46] <abetusk> No
[20:14:04] <ReadError> note: dont cut g10 with a dremel
[20:14:06] <ReadError> it fricken stinks
[20:22:32] <alex4nder> yoh
[20:32:41] <andypugh> I wonder what this actually is? http://www.ebay.co.uk/itm/271130813214
[20:40:30] <cradek> I don't know, but that MT1 looks awfully small on it
[20:45:26] <andypugh> Odd, isn't it?
[20:45:42] <cradek> yeah. I'd like a closer look at the inside
[20:47:44] <andypugh> I might just buy it to see what it is :-)
[20:51:41] <Tom_itx> offset boreing bar?
[20:53:00] <Tom_itx> naw
[20:54:15] <Tom_itx> not for old brace and bit type drills is it?
[20:54:24] <Tom_itx> with the square drive
[20:54:36] <andypugh> I found one auction, "job lot of artutrades". I think he means "Architraves"
[20:54:56] <cradek> Tom_itx: I thought that too, but the MT1 is so wimpy.
[20:55:09] <andypugh> Tapping chuck?
[20:55:18] <andypugh> Roller box?
[20:55:35] <Tom_itx> buy it and let us all know :D
[20:55:57] <skunkworks> I think we have something like that...
[20:56:21] <skunkworks> wonder if dad knows what it is..
[21:05:56] <skunkworks> heh - dad says 'guess i just assumed that was a drill chuck first generation'
[21:06:21] <skunkworks> 'before maybe someone figured out tapers for closing '
[21:08:33] <andypugh> Somehow it doesn't look quite that old
[21:28:57] <skunkworks> andypugh: Close to the bottom... http://www.homemetalshopclub.org/news/mar03/mar03.html
[21:30:47] <andypugh> I wondered if it was for tapping, but rejected the idea as the taper is so small.
[21:31:31] <andypugh> This does make it ideal for rigid-tapping on my lathe though, as I have a few MT1 toolholders.
[21:31:58] <t12> i wonder if my tiny little feedthrough will work
[21:32:04] <t12> https://www.dropbox.com/s/xwmru0qg84nvdfi/2013-01-04%2019.16.08.jpg
[21:33:00] <Tom_itx> slip some heatshrink tube over the wires to help protect them
[21:35:14] <t12> good idea
[21:35:25] <t12> the hole is gonna be epoxy filled too
[21:35:58] <t12> its for a liq n2 tank, so i dunno if the seals on the nuts will work
[21:36:16] <t12> might have to use cryo metal seals if i can make or find them
[21:38:03] <archivist> have a flange at one end rather than a nut
[21:38:16] <archivist> part of screw
[21:39:26] <t12> yah i could just drill out a machine cap screw
[21:40:06] <t12> i guess hex head would be better
[21:43:43] <t12> is there a sane way to 3jaw chuck allthread
[21:43:54] <t12> without destroying the threads
[21:44:07] <Tom_itx> lock 2 nuts together
[21:44:11] <Tom_itx> and chuck on the nuts
[21:45:12] <Tom_itx> maybe not the absolute best way but it would probably work
[21:45:17] <t12> i guess thatd be easier with a 4jaw also
[21:45:28] <t12> due to nut nonconcentricity
[21:46:42] <t12> ill have to take another shot at it tomorrow
[21:48:44] <andypugh> Alternatively, one nut with a saw-cut in the three-jaw.
[21:49:28] <t12> like split nut?
[21:49:50] <andypugh> Yes.
[21:50:28] <andypugh> You could consider making one from scratch if you are not convinced that commercial nuts are concentric..
[21:50:34] <skunkworks> aluminum shim (say .030)
[21:50:53] <t12> the nonconcenrcity likely doesnt mater anyway
[21:50:57] <t12> being obsessive
[21:51:38] <andypugh> bottoming-out in a blind, tapped hole will work too.
[21:52:23] <t12> ahh yeah that makes sense
[21:53:24] <RyanS> how do harmonic drive gears get 100:1 ratio for eg? i watched an animation and i'm only seeing the flexible internal gear being slightly smaller diameter then the outside rigid gear. Where is the reduction derived from?
[21:54:19] <archivist> RyanS, 100 teeth in the inner and it only jumps one tooth per rev
[21:57:58] <skunkworks> t2 how much pressure?
[21:58:25] <t12> for the liqn2 thing? 22psi
[21:58:37] <skunkworks> I would want the oring to be totally trapped.
[21:58:43] <t12> thats where the dewer blowoffs are
[21:58:52] <skunkworks> ah
[21:59:12] <t12> for no oring to n2 exposure?
[21:59:12] <RyanS> so it 'waves' therefore the teeth do not mesh together as often as other types of gears?
[21:59:52] <archivist> yes
[22:00:18] <t12> yeah the oring is def not the right material
[22:01:08] <jdh> brass tubing, slit (chucking all-thread)
[22:01:30] <skunkworks> jdh: ooh - good thinking
[22:01:31] <t12> a gallium oring i think is the right thing
[22:01:39] <skunkworks> even copper water pipe
[22:01:42] <t12> but i dont think theyre made that small
[22:02:07] <t12> could cast one or just cut a hole in some stock and trim
[22:02:23] <t12> im going for wait and see kf it matters
[22:02:27] <t12> if
[22:02:51] <t12> thnx all for the chucking suggests
[22:58:09] <RifRaf> anyone cut smallish involute gears with their cnc machine?
[23:45:39] <theos> hmm