#linuxcnc | Logs for 2012-11-15

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[01:16:41] <DJ9DJ> moin
[02:44:24] <Loetmichel> mornin'
[03:28:10] <DJ9DJ> remoin
[06:44:05] <jthornton> anyone know how to use the teach-in.py script that is in the Axis directory
[06:56:01] <cncbasher_> jt .. you saw the post on the forum too ! .. as far as i can see you jog to position needed and press P and this stores the corrd in a txt file
[07:14:59] <jthornton> so it is loaded with Axis?
[07:45:45] <cncbasher_> i'd guess it's loaded as a terminal app
[07:47:15] <cncbasher_> it's an exe i
[07:47:37] <cncbasher_> iv'e just ran it
[07:48:14] <cncbasher_> move to position press learn and select if you want joint or world mode
[07:49:21] <cncbasher_> entrys show up in terminal window , so can be saved as txt file at the end
[08:16:41] <gmouer> servo question? On a brushed dc, lets say running off a battery, and monitoring the velocity with a scope, would you expect the velocity to be a clean straight line, or show sine wave type small variances? I am thinking of the brushes "pulsing" each winding on the armature there would be small "pulsations" resulting in the velocity. Trying to get my head wrapped around this stuff
[08:16:59] <gmouer> oh yea, no servo drive, just battery power
[08:17:26] <jthornton> what is the command to start it? I tried teach-in and teach-in.py
[08:18:18] <cncbasher_> jt just click it or ./teachin.py should do
[08:18:38] <jthornton> you running it from a RIP?
[08:18:47] <cncbasher_> it's set as run exe
[08:19:13] <cncbasher_> no need to run axis , it's stand alone
[08:19:48] <cncbasher_> i just ran from the directory it was in
[08:20:09] <jthornton> ah, I was trying to figure out if it got installed
[08:20:21] <cncbasher_> ok
[08:20:44] <cncbasher_> would need to be modified for 5 axis though
[08:22:47] <cncbasher_> arh i think it would set the axis as to your installation so would do as many axis as you have set up
[08:24:35] <cncbasher_> a timer and an auto save would help , a sod if you closed the window after half an hours work
[08:33:31] <mrsun> hmm i wonder if i should buy a new hd just for haiku =)
[08:34:47] <mrsun> would be neat with ssd for haiku
[08:34:51] <mrsun> doh :P
[08:34:54] <mrsun> wrong channel ;P
[08:56:12] <pcw_home> haiku, hows Mrs Ku?
[09:24:33] <pcw_home> gmouer: you might see some small variations (especially with cheap 3-5 segment commutator motors)
[09:24:35] <pcw_home> but these would be filtered by the rotor inertia
[09:24:37] <pcw_home> on a brush motor, each armature winding generates a sine wave voltage,
[09:24:38] <pcw_home> but the commutator selects the winding at the peak of the sine wave
[09:24:40] <pcw_home> If you want to see this, run a DC brush motor as a generator, the ripple is apparent
[09:27:50] <mazafaka> https://www.youtube.com/watch?feature=player_embedded&v=je4qV7fsVvU
[10:30:54] <IchGuckLive> Hi all B9
[10:33:02] <IchGuckLive> PCW is there a leeak of supplie to austria ?
[10:46:54] <ktchk> Hi any one working with plasma table?
[10:47:33] <Tom_itx> at least a couple are
[10:52:59] <IchGuckLive> tjb is on the vmashine
[10:55:07] <roh> i wonder how what people use for small closed-loop stepper machines.. any suggestions about such systems?
[10:56:02] <roh> i want to retrofit our china-co2 laser with emc2 soon.. ordered some stepperdrivers with enable inputs since i want to keep the 'manual zeroing' capability
[10:58:18] <roh> i'm still searching for fitting encoders. i will use the steppers in 1/8 or 1/16th microstepping mode and they are 200steps/rotations.. does that mean i need 3200ppr encoders? or will any multiple of 200 already give useable results? (staying withing 1/10th of a mm when it comes to absolute positioning is enough, relative ones should be ok even without encoders i guess
[10:58:51] <ktchk> Tom_itx: what thc is better?
[11:00:39] <IchGuckLive> roh: there are steppers with encoders otherwise you might fit a Gear
[11:00:52] <IchGuckLive> the close loop is only on the error
[11:00:59] <IchGuckLive> there is no correction
[11:01:34] <IchGuckLive> roh you can do it with a arduino in beetween
[11:01:47] <IchGuckLive> that checks the system out and corrects
[11:02:09] <roh> IchGuckLive: i want to have a 'unlock' button like in the china sw and switch off power to the steppers and be able to manual move the laserhead... but emc should register it still
[11:02:46] <roh> ive found how to use encoders in stepper systems in general, but i am not sure about the details of the implementation.
[11:03:29] <IchGuckLive> only one axis
[11:04:16] <IchGuckLive> then just count in the pulses and the dir and set the new axis value
[11:04:18] <roh> the best would be to keep the current steppers (nema 17 i guess) which have axis on both sides and one end is unused or atleast there is space on the axis
[11:04:52] <IchGuckLive> i uses also 2 Axis Steppers nema 23
[11:05:30] <roh> any suggestions about encoders? i was thinking about avago ones for about 20E
[11:06:05] <IchGuckLive> im not with you What you woudt like to do STOP linuxcnc move by ESC then F2
[11:07:04] <roh> i dont want to disable and enable the machine. i want it to follow movement of the head with disabled steppers
[11:07:49] <roh> 17:53 < IchGuckLive> im not with you What you woudt like to do STOP linuxcnc move by ESC then F2
[11:07:52] <roh> eek
[11:08:29] <IchGuckLive> the HED are good
[11:09:20] <IchGuckLive> disable the stepper Driver by ?
[11:09:20] <roh> http://de.farnell.com/avago-technologies/heds-9000-t00/encoder-dreh-2000ppr-2ch/dp/1654866 these?
[11:09:37] <roh> i would add a button in axis (pyvcp or so)
[11:10:07] <IchGuckLive> this will lead in a error as the Enable pin of the driver axis changes
[11:10:19] <roh> 'lock/unlock' or so.. locked is stepperes powered, holding position, unlock is 'move by hand, position follows movement'
[11:10:51] <IchGuckLive> there is a example somwhere for this
[11:11:00] <roh> i should be able to reset the microstepping cycle to 0 by the reset input of the drivers
[11:11:06] <IchGuckLive> someone already did this
[11:11:14] <IchGuckLive> for manuell tool change
[11:11:56] <roh> its just small allegro A4988 drivers.. the motors run at 24V and 2 motors on the same 24V psu.. so coil current can't be too high
[11:12:19] <IchGuckLive> what is your SCALE
[11:12:40] <IchGuckLive> are the steppers direkt monted
[11:12:54] <IchGuckLive> or pulley system
[11:13:05] <roh> so i'd set that up like a regular 'closed loop' stepper with stepgen in velocity mode with a pid loop and the encoder as feedback?
[11:14:01] <roh> the steppers drive pulleys which run the flying mirror and laserhead on the x/y axis. i would just mount the encoders directly on the stepper axis (5mm dia)
[11:14:29] <IchGuckLive> ok
[11:14:46] <roh> the Y stepper is fixed, the X stepper is mounted on the brigde to the left.. basically the same setup all cheap china lasercutters have
[11:15:03] <roh> 'rabbit40' and all of the same oem/odm
[11:16:47] <roh> http://www.electricstuff.co.uk/laserc6.jpg is similar to ours (but smaller)
[11:17:04] <roh> you can see the X stepper in the top-left
[11:17:31] <roh> the pulley runs inside the X rail
[11:23:02] <IchGuckLive> im still searching the file
[11:23:38] <IchGuckLive> http://linuxcnc.org/index.php/english/forum/40-subroutines-and-ngcgui/20912-sheet-alignment-in-a-plasma-table
[11:23:49] <IchGuckLive> roh: look here
[11:24:10] <roh> well.. i ordered some 74hc parts for the chargepump circuit and latching as well as 2 stepperdrivers now.. we'll see what encoders i can get a hold of
[11:26:36] <roh> well.. that seems to be for manual jogging.. and aligning with rotation
[11:26:43] <roh> not really my usecase
[11:38:27] <roh> hm.. about .2mm axis movement per full step
[11:42:55] <IchGuckLive> pcw_home: are you here ß
[12:04:30] <r00t4rd3d> http://web.media.mit.edu/~amitz/Amit_Zoran_home_page/the_freeD.html
[12:04:48] <r00t4rd3d> interesting...
[12:09:31] <sliptonic> I'm looking for documentation on setting up my 5i25/7i77 estop configuration so the linuxcnc condition and the machine condition are in sync. I see something in pncconf about the estop ladder program but I'm not sure how to use it.
[12:14:27] <tjb1> r00t4rd3d: maybe that will make your aluminum supports for you ;)
[12:24:11] <tjb1> JT-Shop: I just had an idea, I wonder if I can use the VFD output on the G540 to adjust the voltage the arduino adjusts too.
[12:44:08] <IchGuckLive> PCW ARE YOU ON ?
[12:53:44] <roh> hm.. maybe i just put some optical mouse sensors next to the belt
[12:55:04] <IchGuckLive> roh: im just not getting you why do you need a closed system on that
[12:55:32] <IchGuckLive> you can do 300iPm with no steplos on parport
[12:56:45] <archivist> accuracy
[12:57:10] <archivist> steppers are not accurate when microstepped open loop
[12:57:14] <roh> IchGuckLive: to be able to manually move the head and emc follow that movement
[12:57:20] <IchGuckLive> on a 1mm round laser point
[12:57:52] <IchGuckLive> to record shapes back to G-code
[12:58:00] <IchGuckLive> or DXF
[12:58:29] <roh> its ok if the manually positioned coord. changes a few 10th of a mm when locking again
[12:59:18] <roh> mostly to quickly align stuff where you leave over some mm of material anyhow (rest pieces of wood etc)
[12:59:21] <IchGuckLive> with pyvcp you can read the parameters out of emc.var
[12:59:35] <IchGuckLive> then with a button set the parameter back
[12:59:47] <roh> well.. to have parameters i need some sensor to read back movement when the steppers are freely moving
[13:00:38] <IchGuckLive> so button push saves the value of your z / then move your mashine by hand and reset the parameter back
[13:01:08] <IchGuckLive> maybe my engl is not good enoph to get your needs
[13:02:15] <roh> the current sw doesnt use any real absolute positioning. thats why i want to add emc. but for 'quickies' on the lasercutter where absolute coordinates arent neccessary its really nice how it works right now:
[13:02:31] <IchGuckLive> you can put a encoder direct to your Axis spindle then record this from bottom press manuell
[13:03:27] <IchGuckLive> if you press then another button you can calculate the numbers into the system back
[13:03:46] <roh> every object imported into the cutting sw cuts from 'current pos' .. so its always relative mode! and there is a manual jog box obviously.. which has a 'unlock' button.. which disables the steppers, so you can just push the head where your 'workpiece 0/0' is and press test.. if you like it, start cutting.
[13:04:55] <IchGuckLive> thats Called Workpice ofset
[13:05:00] <roh> but that sucks since engraving stuff with a helper to align many pieces successively at the same position isnt fun since one needs to 'manually find 0/0' every time again. bad reproducability.
[13:05:23] <roh> sure. i know how emc handles that. we got it on our cnc mill
[13:05:34] <IchGuckLive> you can set G54-G59
[13:05:51] <IchGuckLive> you can set this by button
[13:06:10] <roh> of course. but the other users of the machine would like to keep the possibility to 'unlock' the steppers to find the workpiece 0
[13:06:20] <roh> without losing the absolute pos.
[13:06:42] <IchGuckLive> i woudt sucess then a Homing
[13:07:01] <archivist> why not just use axis, jog and touch off no need for manual moving of the motors
[13:07:41] <roh> archivist: still much more annoying than just grabbing the head and positioning it over the wood/acryllic
[13:07:52] <IchGuckLive> roh it is yust a bad behavier of using the system
[13:08:16] <roh> i'd call it 'workflow convenience' ;)
[13:08:37] <roh> both usecases have their pros and cons. sure. thats why i think about a solution
[13:08:45] <IchGuckLive> ok then try it and give us a feedback
[13:08:53] <roh> i will for sure
[13:09:31] <roh> what would be a 'recommended' encoder-steps to stepper-steps ratio anyhow?
[13:09:52] <roh> is 1:1 ok?
[13:10:22] <IchGuckLive> ok then go as you think Button press releses a Relay that disconnects the Driver stage so the stepper is free and the linuxcnc is on Stepper enabled
[13:10:25] <roh> not specific to my usecase, rather since i cannot find any 'best practices'
[13:10:53] <roh> the steppers have enable inputs, so i dont even need a relay
[13:11:12] <IchGuckLive> i woudt go for 2048 ppr on the encoder they are cheep what is your pich
[13:11:33] <Aero-Tec> thanks to all that helped me get my lathe going
[13:11:56] <IchGuckLive> roh if you change the pinstate of the xenable pin linuxcnc will go on error so relay is needed
[13:12:10] <Aero-Tec> looks like it is now fixed and ready to use, but I have said that before so I hope this time is for real
[13:12:18] <roh> i just measured travel distance to rotations and would say that its 40.6mm travel per motor rotation
[13:12:22] <IchGuckLive> Aero-Tec: 7i77 spindel
[13:12:32] <Aero-Tec> I wish
[13:12:39] <Aero-Tec> would be great
[13:12:57] <Aero-Tec> I got my home made encoder fixed
[13:12:58] <IchGuckLive> Aero-Tec: can you post your ini hal
[13:13:37] <Aero-Tec> add a pn2222a transistor
[13:13:40] <roh> IchGuckLive: i think i'll just use different pins then. also i'll reset the microstepping cycle on reenabling, so i dont start inmidst a step... after powerdown the stepper will be on a fullstep anyhow i guess
[13:13:52] <IchGuckLive> roh: one rotation of the axis spindle 40mm
[13:14:01] <Aero-Tec> got the sig low down from .88 to .03
[13:14:14] <roh> IchGuckLive: maybe. was nothing precise, just a zollstock
[13:14:28] <IchGuckLive> that is quit large roh
[13:14:42] <Aero-Tec> so now EMC sees a proper low
[13:15:18] <Aero-Tec> do you want them posted on the same past bin?
[13:15:23] <roh> IchGuckLive: well.. chinese laser cutters.. every corner has be cut ;)
[13:15:27] <Tom_itx> IchGuckLive what page is the 7i77 on?
[13:16:25] <IchGuckLive> Tom_itx: europ or usa
[13:16:26] <Aero-Tec> the opto was a darlinton so it did not have a low voltage turn on
[13:17:20] <Tom_itx> i found it
[13:17:38] <Aero-Tec> IchGuckLive: do you want to separate paste bins or one large one for the ini hal?
[13:17:46] <Aero-Tec> two
[13:17:48] <Aero-Tec> oops
[13:17:55] <IchGuckLive> up to you
[13:20:10] <archivist> roh you do realise just dragging a stepper with an encoder will probably give you a following error as linuxcnc did not command it
[13:20:45] <roh> archivist: yes.. i an still thinking how to work around that
[13:21:28] <archivist> just jog normally you will get stuff working a lot quicker
[13:26:43] <IchGuckLive> im off By Aero-Tec i read the log if you post the link
[13:27:27] <Aero-Tec> ok
[13:27:41] <Aero-Tec> have the ini but the hal is being a pain
[13:37:11] <Aero-Tec> for some reason linux is not letting my windows computer open a hal file
[13:37:52] <Aero-Tec> I had it open in a editor but closed it down and also closed down EMC as well
[13:38:16] <Aero-Tec> now nothing is open on the linux machine and still it will not let me open file
[13:44:35] <tjb1> Is there any documentation about using a vfd output on a controller with linuxcnc?
[13:48:43] <tjb1> Got it :)
[13:49:13] <tjb1> If I configure PWM spindle speed and set a scale does it take the M3 SXXXX and send PWM based on that?
[13:50:50] <andypugh> Yes
[13:52:22] <andypugh> I just removed the VFD controller from my machine. I am hoping that the 7i49 can do the same job, as I have no PWM outputs.
[13:53:25] <tjb1> Well the G540 takes a PWM input
[13:55:13] <tjb1> Im trying to get to where M3 S117 will tell my arduino that desired arc voltage is 117 and adjust it
[13:55:50] <andypugh> It almost certainly already does. Put a halmeter on motion.spindle-speed-out
[13:56:14] <andypugh> Ah, sorry, that doesn't tell the Arduino, does it?
[13:56:32] <tjb1> Hmm?
[13:56:49] <tjb1> G540 takes the PWM and makes a 0-10v signal
[13:57:26] <tjb1> arduino will take that after being divided to 0-5v and ill use some fancy math to make that into a voltage I want :)
[13:58:04] <tjb1> Max voltage I see in the charts is 146 so I will do a max spindle speed of probably 150-155
[13:58:54] <andypugh> What is the Arduino bringing to the party?
[13:59:28] <andypugh> Why not connect the G540 direct to the plasma?
[13:59:57] <tjb1> Arduino is taking the plasma arc voltage and comparing it to the VFD input to it
[14:00:12] <andypugh> OK.
[14:00:12] <tjb1> sends outputs for torch up/down and then JT's thcud does the work
[14:01:19] <tjb1> Does that sound logical?
[14:01:28] <tjb1> I forgot about the G540 vfd output
[14:02:19] <andypugh> There is a Mesa standalone widget for exactly this application. The Arduino might struggle with the EM noise.
[14:02:40] <tjb1> If I do a max of 160 rpm I get .0625 volts per RPM which should work nice
[14:03:29] <tjb1> If RPM was set to 250 would it just go to the 160 setting?
[14:04:44] <tjb1> Those mesa cards are expensive, if this fails I guess I will be buying one but I am trying to avoid that
[14:06:27] <andypugh> Mesa THCAD is $70
[14:06:49] <andypugh> So you can blow up 2 Arduinos before you are in the red.
[14:07:08] <tjb1> arduinos are only $8
[14:07:24] <tjb1> :)
[14:09:45] <tjb1> The atmega328p is only $5 with bootloader on it on ebay and then just a few caps, oscillator and add i/o where you need them
[14:12:54] <tjb1> Ive already had the arduino hooked up to the plasma and it sampled voltage correctly
[14:21:31] <Aero-Tec> the ini and hal files asked for
[14:21:35] <Aero-Tec> http://pastebin.com/szDPvAvV
[15:03:15] <Aero-Tec> kind of dead
[15:34:16] <mevon> hi andypugh, got my mill moving with simulation .hal but its seems it is using servos, I will change that to steppers today
[15:34:42] <mevon> hence the create a parport dummy
[15:35:32] <mevon> I will do has you told me first, get all the stuff I dont need out now that I know a little bit more about HAL thaks to all you
[15:36:24] <mevon> just need to learn more about stepgen now
[15:36:37] <mevon> and rewire my arduino msgs
[15:38:57] <tjb1> Anyone know if a SheetCAM license will work on 2-3 computers?
[15:58:49] <DJ9DJ> gn8
[16:04:43] <andypugh> mevon: Do you need stepgen?
[16:05:16] <mevon> i will be using that but idk what it is actually
[16:11:11] <andypugh> I have a feeling that the arduino makes the steps, so you don't need the HAL stepgen
[16:11:28] <andypugh> stepgen makes step pulses, generally through the parallel port
[16:13:16] <mevon> I have the two options here, setting a cmd or position, assume like a servo with or without feedback that it goes to the postion and wish linuxcnc will no go too fast before the next cmd is sent, so the servo can reach its pos
[16:13:55] <mevon> but want to try flooding the arduino with step msgs
[16:14:27] <mevon> so to have better precision since i dont have any feedback yet implemented
[16:15:25] <andypugh> The Mesa and Pico cards (with LinuxCNC) and Smoothstepper (with Mach) all work by being sent positions digitally, and generating the required steps to get there internally. It's a well-tested and effective method.
[16:15:52] <andypugh> I really don't think you want to be sending step pulses to the Arduino, it simply won't have a fast enough link.
[16:16:05] <andypugh> 50kHz step rate is fairly common.
[16:17:56] <mevon> obviously the stepping will be slower, and the way you described those project is how its working now
[16:18:52] <andypugh> It's the only possible way to cope with USB latency
[16:19:33] <andypugh> A USB message can wait 1mS (possibly more) before it gets sent by the hardware. No way can you send 50kHz pulses that way.
[16:20:07] <mevon> im just wondering how linuxcnc deals with moving 2 axis or more and makes em finish at the same time since it doesnt have control on the speed
[16:21:28] <andypugh> It sends a position update for every axis every mS. The accelleration and velocity control are part of that.
[16:22:19] <andypugh> It doesn't say "Go from 50mm to 75mm", it says "50, 50.0001, 50.0005, 50.0010, 50.0020....."
[16:23:08] <mevon> so smoothstepper you said Ill check that out
[16:23:27] <andypugh> It's expensive and only works with Mach
[16:28:38] <mevon> i was trying to acheive that ultimately by tweaking the msg sent for more steps at a time, but was hoping I could find an integrator thatd vary the lengths to get more precision at the end of each move
[16:29:28] <mevon> but cmd is the final position and some sort of stepping in between is needed
[16:29:37] <mevon> hence stepgen
[16:31:33] <mevon> has for the step rates, my stepper drive, im not sure it can take more than 1kHz step rate
[16:33:07] <mevon> 10kHz is not acheivable for me right now
[16:38:51] <mevon> do I need parport read write reset base-thread?
[16:39:34] <mevon> I mean what are those for/
[16:39:35] <mevon> ?
[16:47:34] <mevon> max 5kHz to 25kHz for stepgen, 1Khz Im ok
[16:49:12] <mevon> cannot go 9axis with stepgen? humm
[16:55:58] <skunkworks> the stepgen is limited to 8 axis - but that is just a software limitation... I think you could change stepgen.c to allow more.
[16:56:38] <skunkworks> http://git.linuxcnc.org/gitweb?p=linuxcnc.git;a=blob;f=src/hal/components/stepgen.c;h=c091146404d5867c0f1e4483f75b2538d10618b3;hb=HEAD
[17:00:05] <skunkworks> I don't know if the only thing you have to change is line 307...
[17:00:17] <andypugh> mevon: If you don't have a parallel port then you don't need the reset.
[17:00:43] <andypugh> I don't think you even need a base thread.
[17:01:24] <mevon> ok so they are not related to stepgen and not needed, if i dont link to the parport
[17:01:45] <mevon> i bet its for io mgmt
[17:02:05] <andypugh> No, they are intimately related to stepgen. But stepgen is no use to you
[17:03:48] <skunkworks> wait - are you trying to get the usb arduino thing working still?
[17:03:51] <andypugh> The way stepgen works: Every 1mS (servo-thread) it looks at the commanded position, runs the stepgen.N.capture-position function, and caculates how many pulses it needs to make at what rate to get there before the next mS is up. Then every base-thread (typically 25uS) it sets a parallel port pin high or low.
[17:04:44] <andypugh> skunkworks: I have been assuming that, but I could be wrong and perhaps he has seen sense
[17:04:54] <skunkworks> heh
[17:06:08] <Jymmm> Is thee a way to just look at a regulator and tell if it's single or dual stage?
[17:06:56] <andypugh> Yes, read what is says on the label :-)
[17:07:21] <Jymmm> andypugh: I've never seen them state either way.
[17:07:50] <t12> can the whole servo loop be moved into something like a 7i80db
[17:08:17] <andypugh> t12: Yes, that is what SoftDMC does
[17:08:40] <t12> is it effective? a pain?
[17:09:24] <andypugh> All I know on the subject was contained in the previous sentence
[17:09:36] <andypugh> PCW is your man
[17:10:06] <Jymmm> IF HE CANT DO IT NOBODY CAN!!!
[17:10:18] <skunkworks> t12: what are you hoping to do? (linuxcnc works great controlling the servo loop)
[17:11:12] <t12> i'm just curious, no task at hand
[17:11:41] <t12> it seems like a large amount of hassle goes into the rtos on x86 issues
[17:12:04] <skunkworks> ah - but that does make a very very very very flexable system....
[17:12:10] <t12> agree
[17:12:45] <skunkworks> where all setup is done in one place.
[17:58:40] <ve7it> has anyone tried turning multistart threads with linuxcnc? I am trying to code up a 4 start thread... basically do I just offset the start z by 1/4 the pitch?
[17:59:17] <andypugh> Yes, that's how you do it
[18:00:43] <ve7it> cool... I have been playing with threading.ngc in the samples.... I notice it offsets the tool a little on each pass... it looks like this is to cut only with the leading edge of the threading tool
[18:01:18] <andypugh> That's a parameter in the G76 line, the "compound angle"
[18:03:06] <ve7it> ok, the example is using g33 and I am trying to figure out how to due proper leadin and leadout.... a nut doesnt have to fit... it is a winding form for a tig welding machine HF coil.
[18:03:41] <andypugh> G76 has in and out taper I think
[18:04:11] <ve7it> Thanks andy, I'll have a play
[18:05:09] <mevon> wish I knew how to sniff usb com in a term window
[18:05:22] <andypugh> I doubt you can
[18:05:51] <andypugh> unless you can do something funny with /dev/usb0
[18:06:41] <mevon> humm if i chose something like /dev/ttys1
[18:06:52] <mevon> instead of ttyusb0
[18:07:10] <andypugh> I was guessing
[18:07:12] <mevon> and put a screen on the other end
[18:07:50] <mevon> i need some sort of a loop
[18:12:21] <mevon> http://embeddedfreak.wordpress.com/2008/08/12/using-gnu-screen-to-debug-your-serial-port/
[18:52:24] <JT-Shop> http://jamesriser.com/Magic/HeavyRiserStageAndStreetCups.pdf
[18:57:37] <TekniQue> nice work
[18:57:42] <TekniQue> what are those cups used for?
[18:59:09] <JT-Shop> stealing money from unsuspecting people or for a street show
[19:02:01] <TekniQue> I keep wanting to try spinning bellmouths on stainless and aluminium pipe ends on my lathe
[19:02:15] <Tom_itx> do you have to anneal that partway thru the spinning process?
[19:02:23] <JT-Shop> yes
[19:02:38] <Tom_itx> just torch it while it's still on the lathe?
[19:02:57] <ReadError> is that yours JT-Shop ?
[19:03:09] <JT-Shop> the link?
[19:03:11] <JT-Shop> no
[19:05:41] <Tom_itx> early on, i bet it makes you wonder if it will ever turn out
[19:06:02] <ReadError> they look good
[19:07:29] <andypugh> I have done some metal spinning. It's a lot of fun.
[19:07:51] <andypugh> I made some brass oil-tank ends and an acetylene reservoir.
[19:08:40] <andypugh> I needed to anneal the brass multiple times, and I was only turning up a 1/2" lip.
[19:09:22] <JT-Shop> could you feel it getting harder as you spun the part?
[19:09:46] <andypugh> Yes, then it cracks and splits, flies off and attacks you.
[19:10:51] <JT-Shop> so just before it attacks you take it out and anneal it?
[19:11:21] <andypugh> That seems to be the trick :-)
[19:11:43] <Tom_itx> you wanna catch it before the stress cracks show up
[19:14:26] <JT-Shop> http://www.youtube.com/watch?v=Z0R6n6APMuU
[19:19:06] <Tom_itx> I wonder what rpm is used
[19:19:46] <JT-Shop> the ones I saw spinning outdoor light covers was moving right along
[19:20:00] <JT-Shop> they were CNC metal spinners
[19:21:06] <TekniQue> 00:55:44 < andypugh> I made some brass oil-tank ends and an acetylene reservoir.
[19:21:13] <TekniQue> acetylene reservoir sounds dangerous
[19:21:39] <andypugh> No, not really. For a motorcycle lighting set.
[19:21:54] <TekniQue> what's that?
[19:22:08] <TekniQue> a headlight?
[19:22:12] <TekniQue> gas headlight?
[19:22:22] <andypugh> Yes, gas headlight and tail-light
[19:22:58] <JT-Shop> pump it up more for a stop light?
[19:23:11] <andypugh> http://en.wikipedia.org/wiki/Carbide_lamp
[19:23:38] <JT-Shop> lol, yes I know what they are, I'm just pulling your leg
[19:24:14] <tjb1> Oh that time has come for Wikipedia...
[19:24:39] <andypugh> I had an idea for a rotating shutter powered by convection, and a cable-stopper to make acetylene powered indicators. :-)
[19:24:49] <JT-Shop> cool
[19:27:18] <andypugh> I have a couple of carbide cave lights, still very much a current product: http://www.petzl.com/files/all/technical-notice/headlamps/E50%20Ariane%20E50500-02%20030402.pdf
[19:32:36] <tjb1> andypugh: how much light do these give off?
[19:33:36] <andypugh> A huge amount. In all directions. Much more pleasant to cave with than an electric light, you can look around with your eyeballs, not your head.
[19:34:08] <andypugh> Defnitely my preferred caving light source, but a bit frowned upon nowadays.
[19:36:09] <ds3> where does one buy carbide for those lamps?
[19:36:43] <andypugh> Caving shops, vintage vehicle suppliers.
[19:40:30] <andypugh> Anyway, enough of this. Goodnight
[19:40:41] <tjb1> bye andypugh
[20:21:53] <tjb1> Anyone know how many computers you can use a Sheetcam TNG license on?
[20:43:17] <L84Supper> tjb1: my guess is at least one :)
[20:43:27] <tjb1> I would hope so :)
[20:45:21] <L84Supper> I've never seen that CAM package before
[20:46:26] <tjb1> Well its either that or UniGraphics…I couldnt decide
[20:48:25] <L84Supper> NX is great
[20:49:11] <tjb1> $189 vs $100k :P
[20:49:27] <L84Supper> tough call
[20:50:26] <tjb1> How difficult is it to learn vs mastercam/solidworks/autocad?
[20:50:42] <mutilator> i think its impossible
[20:50:47] <L84Supper> NX is similar to solidworks
[20:51:20] <tjb1> Our school apparently cant afford it…I never heard of it until an employer at the job fair asked if I knew it
[20:51:31] <L84Supper> I've used autodesk inventor but never really used autocad
[20:51:36] <tjb1> I hate inventor
[20:51:54] <tjb1> What do you use for 2d drawings or do you do everything in the parametric programs?
[20:52:03] <L84Supper> NX is more powerful than solidworks
[20:52:14] <tjb1> I know
[20:52:18] <tjb1> Its cad/cam in 1 package
[20:52:20] <L84Supper> I pretty much use NX and Solidworks
[20:52:52] <L84Supper> I've used ProE/ Creo as well
[20:53:16] <L84Supper> the industrial designers tend to like Creo
[20:53:18] <tjb1> What do you think is the best?
[20:53:29] <L84Supper> NX
[20:54:10] <tjb1> I wish I could play with it
[20:54:15] <L84Supper> then either Solidworks or Creo based on preferences
[20:57:02] <tjb1> just like solidworks…~$150 for a year
[20:57:35] <L84Supper> Student Edition?
[20:57:44] <tjb1> Yes
[20:57:47] <r00t4rd3d> lol
[20:58:05] <tjb1> Yes r00t4rd3d I know the alternatives...
[21:01:44] <L84Supper> Solidedge is another