#emc | Logs for 2009-03-15

[00:40:45] <judedude> Fenn and Eric I have good news
[00:49:09] <judedude> Parpot configured and works. Still received a home limit error. I used a scope and found that the hobby cnc board has quite a bit of noise.
[00:50:21] <cradek> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?HobbyCNC
[00:50:46] <judedude> I noted a regular pulse that went +/- 3v for 80 micro seconds. I believe that was falsly tripping limit errors
[00:51:15] <cradek> bbl
[00:52:07] <judedude> I used a 0.01 uf capacitor and now it works.
[00:52:52] <Guest111> minor documentation patch: http://pastebin.ca/1361105
[01:15:58] <Optic> will emc2 step muliple axis simulataneously?
[01:16:05] <Optic> can xstep and ystep be active at the same time?
[01:18:59] <dmess> go for it
[01:34:00] <Optic> when emc2 does a g0 move, does it do it at MAX_VELOCITY?
[01:34:12] <bglackin> yes
[01:34:16] <SWPadnos> yes, for all the involved joints
[01:34:19] <Optic> cool
[01:34:27] <SWPadnos> or the TRAJ limit, whichever is lower
[01:35:08] <Optic> we're having some trouble with the system losing alignment, but we're debugging
[01:35:20] <Optic> we're trying to figure out if it's mechanical or our stepper control
[01:35:25] <Optic> we trust emc :)
[01:35:30] <SWPadnos> heh
[01:35:38] <SWPadnos> you can also test uwing a "bare HAL"
[01:35:38] <bglackin> Homebrew controller?
[01:35:39] <SWPadnos> using
[01:35:43] <Optic> yeah
[01:35:52] <SWPadnos> load a stepgen, parport, and a siggen component
[01:36:10] <Optic> http://hacklab.to/archives/laser-engraver-is-alive/
[01:36:20] <Optic> we're using stepgen and parport
[01:36:28] <Optic> original config was made with the stepper wizard
[01:36:33] <Optic> but we've changed it quite a bit since then
[01:36:35] <SWPadnos> connect the sine wave, or if you want to test accel/vel limits the square wave output, from the siggen to the stepgen. you can change the frequency and amplitude of the signal on the fly with halcmd
[01:36:43] <SWPadnos> I'm talking about HAL, without EMC running
[01:36:49] <Optic> oh cool
[01:36:56] <SWPadnos> just the parport driver, the step generator, and the signal generator
[01:37:04] <Optic> that's a good idea
[01:37:15] <SWPadnos> and you can load up a scope and several meters
[01:37:22] <SWPadnos> so you can see what's happening
[01:37:54] <SWPadnos> for debugging, it's best to reduce the system to the smallest thing that will exhibit the problem
[01:38:00] <Optic> yes
[01:38:35] <Optic> and we should make a simple gcode that just draws a series of boxes
[01:38:57] <SWPadnos> a siggen or two will do that nively also
[01:39:08] <L84Supper> is the USB supported on the Mesa 7i43? I only see EPP in the driver source.
[01:39:15] <SWPadnos> there are simultaneous sine, cosine, square, triangle, and sawtooth outputs
[01:39:21] <SWPadnos> L84Supper, no
[01:39:27] <SWPadnos> only for power, I think
[01:39:34] <SWPadnos> (and maybe not that)
[01:39:45] <L84Supper> so I'd have to add USB support
[01:40:06] <SWPadnos> well, that's a much more complex task than you probably think, but yes - you would
[01:40:23] <L84Supper> yes, I didn't say it was simple :)
[01:41:42] <SWPadnos> it's not just the 7i43 driver that would need to change. you'd have to write a driver for the USB host controller, figure out how to prevent Linux from using it, and make changes to the core of how EMC handles hardware
[01:42:07] <L84Supper> thats what I'm trying to look over
[01:45:17] <L84Supper> what's the contention over the USB host with the kernel and emc2?
[01:45:40] <SWPadnos> USB and all normal Linux drivers are inherently non-realtime (in the context we need)
[01:45:55] <L84Supper> oh ok
[01:46:15] <L84Supper> yes , it be tweaked for real time
[01:46:29] <SWPadnos> not just that
[01:46:42] <SWPadnos> emc2 expects to be able to read and write information in real time
[01:47:00] <SWPadnos> USB always introduces some lag for any feedback data (such as encoder inputs or GPIO)
[01:47:09] <SWPadnos> and there's also lag for command data
[01:47:51] <SWPadnos> so the trajectory planner, which is in the RT kernel on the PC, doesn't have a good connection to the real world that it's trying to control
[01:48:18] <L84Supper> yes, it depends on the application, I may have a softcore in the fpga to handle this for my app
[01:48:32] <SWPadnos> the FPGA side is the easy part
[01:49:10] <SWPadnos> USB is fine if you have a "set it and forget it" system - you output a burst of positions which get played back at a fixed rate
[01:49:23] <SWPadnos> and you don't care whether you get feedback data quickly
[01:49:33] <jmkasunich> Optic: neat vid
[01:49:38] <L84Supper> yes, i see the latency issues
[01:49:58] <Optic> it works pretty well!
[01:49:59] <SWPadnos> this screws up things like feed override on a CNC, and also makes it a requirement that anything like spindle synchronization or electronic gearing be done on the FPGA
[01:50:07] <L84Supper> anyone ever port emc2 to ARM or Microblaze?
[01:50:26] <SWPadnos> definitely not Microblaze (AFAIK), there's abeen a lot of talk about ARM
[01:50:58] <L84Supper> I'm just digging into emc2 again
[01:51:48] <L84Supper> what's the size of the binary on x86?
[01:51:53] <SWPadnos> no idea
[01:52:01] <SWPadnos> there are a number of binaries that make up emc2
[01:52:16] <SWPadnos> how long ago did you stop looking at EMC? :)
[01:52:20] <L84Supper> yes, depends on the features used
[01:52:32] <SWPadnos> well, yes and no
[01:52:54] <SWPadnos> there was always a split between task and motion (and probably IO as well)
[01:52:57] <L84Supper> about a year, forgot much of it already, just refreshing
[01:53:11] <SWPadnos> ok, wasn't sure if you ever saw the whole HAL thing
[01:53:44] <SWPadnos> lots of little components for small functions (usually - the motion controller is also a HAL component)
[01:55:07] <L84Supper> just looking at control over USB vs PCI for some applications
[01:55:52] <L84Supper> simple on/off motor stuff and similar
[01:56:01] <SWPadnos> there's a device called the ncPod, which uses a Windows EMC2-based interpreter and sends position data to a USB connected device
[01:56:14] <SWPadnos> the source code is available, though not always easy to find
[01:56:19] <SWPadnos> the company is OEMTech
[01:56:22] <SWPadnos> iirc
[01:56:24] <L84Supper> thanks
[01:56:28] <SWPadnos> sure
[01:57:46] <L84Supper> found the binaries
[01:58:04] <SWPadnos> there's source too
[01:58:19] <SWPadnos> but don't come here with questions :)
[01:58:29] <L84Supper> i understand
[01:58:38] <SWPadnos> (we're unlikely to know the answers, really)
[01:59:31] <L84Supper> grabbed the sdk
[01:59:45] <SWPadnos> cool
[01:59:47] <L84Supper> I'll dig
[02:00:06] <SWPadnos> now if you figure out something that could make USB position lists work in Linux, definitely come back ;)
[02:02:49] <SWPadnos> (hmmm - I hope that didn't seem like I was being a jerk - it's just that we don't have anything to do with their codebase)
[02:03:08] <L84Supper> is there any demand for prepackaged debs for emc2?
[02:03:20] <L84Supper> don't worry :)
[02:03:54] <SWPadnos> we provide Ubuntu .debs. if you have ideas on how to make those OS-agnostic, please do tell
[02:04:11] <L84Supper> I'm usually dealing with coreboot, grub and x developers
[02:04:27] <SWPadnos> hmmm. cool
[02:04:33] <SWPadnos> coreboot was LinuxBIOS, right?
[02:04:34] <L84Supper> it's civilized in here : )
[02:04:36] <SWPadnos> heh
[02:04:38] <L84Supper> yeah
[02:04:44] <SWPadnos> nice
[02:05:03] <SWPadnos> I've never gotten to the point of putting it on any of my machines, but I'd love to try
[02:05:14] <L84Supper> I can hide a usb host from the kernel with coreboot
[02:05:17] <SWPadnos> I think I have a SuperMicro motherboard that would work, but it's not specifically listed
[02:05:26] <L84Supper> init it later
[02:05:33] <SWPadnos> you may be able to use some udev rule as well
[02:05:50] <SWPadnos> almost everything is initialized with hotplug these days - even CPU cores
[02:05:50] <L84Supper> yes, we do that with VirtualBox
[02:06:36] <SWPadnos> hmmm. unrelated question: do you know any virtualization (or Wine-like) solution that would allow me to run a Windows app that needs DirectX 9.0c, Shader model 3?
[02:06:51] <L84Supper> looking at using EMC for printer control
[02:07:22] <SWPadnos> I think Wine is getting there - they have some new DX10 code now, but I always seem to hit a dead end at Shader Model 2
[02:07:37] <L84Supper> we have it working and shader 4
[02:07:44] <SWPadnos> ??
[02:07:47] <SWPadnos> can I buy that?
[02:07:55] <SWPadnos> or get it free :)
[02:08:15] <L84Supper> heh, my 16 year old son got it up
[02:08:24] <L84Supper> have to check with him
[02:08:24] <SWPadnos> hmmm
[02:08:42] <L84Supper> with a little help
[02:08:51] <SWPadnos> pixel shader or virtex shader?
[02:09:06] <L84Supper> both
[02:09:10] <SWPadnos> huh
[02:09:19] <L84Supper> which graphics card?
[02:09:24] <SWPadnos> well, definitely let me know - I'd love to be able to run Altium under Linux
[02:09:43] <SWPadnos> I have nvidia and ATI - Quadro FX3500, some 9600GT
[02:09:45] <SWPadnos> argh
[02:09:51] <SWPadnos> 9500GT, and an ATI HD4870
[02:10:00] <L84Supper> you'll need the restricted Linux drivers for your gpu
[02:10:10] <SWPadnos> and I'll gladly buy a GTX260 or later if necessary ;)
[02:10:16] <SWPadnos> yep, I use the restricted drivers
[02:10:20] <L84Supper> he said it's a snap, it's in hardware
[02:10:32] <SWPadnos> gotta get those 13000 FPS rates in glxgears ;)
[02:10:45] <L84Supper> he has it working on his old 9800pro
[02:10:48] <SWPadnos> yeah, the hardware supports it, but I don't know that the libraries do
[02:10:54] <SWPadnos> ok, cool.
[02:10:56] <L84Supper> he got it
[02:10:58] <SWPadnos> radeon or geforce?
[02:11:07] <SWPadnos> they both had 9800s I think
[02:11:10] <L84Supper> radeon
[02:11:12] <SWPadnos> ah
[02:11:37] <SWPadnos> do you know if he's using wine, or did he install Windows libraries
[02:12:01] <SWPadnos> maybe I have a different problem with Altium - it could be a 32/64 bit thing or something else
[02:12:07] <L84Supper> eveything can be done in Wine
[02:12:28] <L84Supper> give him an hour for a howto
[02:12:35] <SWPadnos> heh. OK - will do ;)
[02:12:54] <L84Supper> for ubuntu 8.04 or?
[02:13:09] <SWPadnos> I have 8.04, 8.10, and 9.04 alpha - I can take my pick
[02:13:16] <SWPadnos> and I can compile for myself if needed
[02:13:25] <SWPadnos> wouldn't be too long on the Phenom x4
[02:13:37] <L84Supper> he's typing away
[02:13:46] <SWPadnos> wow. great - thanks
[02:13:50] <L84Supper> 8.10 howto
[02:13:50] <SWPadnos> glad I asked :)
[02:14:10] <SWPadnos> ok, perfect. I think that's what's on the Phenom at the moment
[02:14:11] <L84Supper> sure, I'm trying to keep him busy and out of trouble :)
[02:14:15] <SWPadnos> with the HD4870
[02:14:17] <SWPadnos> heh
[02:14:25] <SWPadnos> well, anything I can do to help, you know
[02:14:28] <SWPadnos> :)
[02:15:30] <SWPadnos> I'd almost rather have it in VMWare (where it runs fine but doesn't do the cool stuff without SM3), but wine is fine too
[02:17:45] <L84Supper> have you tried virtualbox?
[02:17:49] <SWPadnos> yes
[02:18:03] <SWPadnos> virtualbox, vmware, and several wines
[02:18:24] <SWPadnos> including Transgaming or whetever they call it now
[02:19:27] <L84Supper> debugging an issue now with virtualbox on 8.10 with WinXP on the VM
[02:19:55] <L84Supper> USB stuff
[02:20:00] <SWPadnos> ah
[02:20:09] <SWPadnos> pro or free version?
[02:22:06] <L84Supper> free binary version, the open version does not support USB yet
[02:22:41] <SWPadnos> right - that was what I thought
[02:22:49] <SWPadnos> is that no USB at all, or just no USB2?
[02:22:58] <L84Supper> I have a device with 2 different product ID's, with a Cypress USB2.0 and fpga behind that
[02:23:32] <SWPadnos> 2 product IDs - that sounds a little odd
[02:23:36] <SWPadnos> 2 endpoints I can imagine, of course
[02:24:02] <SWPadnos> but then again, I have one like that too - the Belkin Nostromo game controller looks like two devices
[02:24:09] <L84Supper> yes, one is the USB device before the FPGA gets loaded and the other is what the device becomes after
[02:24:52] <L84Supper> not sure if virtualbox can handle the USB ID shell game yet :)
[02:25:07] <SWPadnos> heh
[02:25:51] <SWPadnos> I guess I should look into how all this works at some point. I might want to snoop some USB traffic soon, and doing it in a virtual machine seems like a reasonably good way of doing that
[02:25:58] <L84Supper> why I was asking about the Mesa boards
[02:28:04] <L84Supper> 32 bit or 64 for the dx9 suppot?
[02:28:25] <SWPadnos> well, my hosts are 64-bit, and I have XP64 pro - so I guess 64
[02:29:23] <L84Supper> done, maybe I'll get him to package emc2 in .rpm or for Gentoo
[02:29:42] <SWPadnos> actually, I think there are ebuilds and RPMs already
[02:29:47] <SWPadnos> but I don't know how recent they are
[02:29:58] <L84Supper> didn't notice them yet
[02:29:59] <SWPadnos> I think you can check on the wiki for those
[02:31:04] <L84Supper> virtex shader 3.0 or 4.0 ?
[02:31:58] <SWPadnos> not sure - I don't think that will matter
[02:32:31] <L84Supper> pixel or viretx, pretty sure one is ATI and the other nvidia
[02:32:51] <SWPadnos> both are part of the DirectX spec
[02:33:06] <SWPadnos> I need pixel shader 3
[02:33:25] <SWPadnos> (I think that's it anyway - the specs only say "shader model 3")
[02:33:57] <L84Supper> he got it working about a month ago, the Wine guys didn't believe him and banned him from the irc until he posted a video :)
[02:34:03] <SWPadnos> heh
[02:34:56] <L84Supper> like I said it's civilized in here
[02:35:15] <SWPadnos> hmmm. I'll take that as a compliment :)
[02:36:20] <SWPadnos> this will be fun. I may try to get this to work on my laptop as well, so I can show the Altium guys at the ESC conference later this month :)
[02:40:29] <Optic> do some pc serial ports operate at 3.3V?
[02:40:50] <Optic> er, parallel ports
[02:40:55] <SWPadnos> phew
[02:41:04] <SWPadnos> yes, I think many laptop ones may
[02:41:07] <L84Supper> SWPandos : which gpu is in the laptop?
[02:41:21] <SWPadnos> also, there are electrical differences between the various modes (EPP, ECP, SPP)
[02:41:32] <SWPadnos> L84Supper, Geforce 8400m or 8600m
[02:41:58] <Optic> which mode should be using for 5V?
[02:42:03] <L84Supper> the laptop is shader 4.0
[02:42:09] <Optic> the port has "bi-directional" epp and ecp
[02:42:32] <SWPadnos> Optic, bi-directional or epp should work, I think ecp is not good (more often that not anyway)
[02:42:43] <Optic> thanks
[02:42:58] <SWPadnos> L84Supper, I don't know that vertex shader 4 is even out yet - maybe part of DX10 or something
[02:43:06] <Optic> does the bios setting affect linux?
[02:43:42] <Optic> our parallel port seems to be making 3.3v :-/
[02:44:04] <SWPadnos> Optic, yes - you should set the bios to epp or bidirectional
[02:44:25] <SWPadnos> and/or get a breakout/buffer board
[02:44:27] <Optic> ok, it was set to ECP
[02:44:58] <Optic> testing now
[02:47:33] <L84Supper> wish there was an open version of pro-e or solidworks
[02:47:43] <SWPadnos> yeah, that would be nice
[02:48:05] <SWPadnos> there's a very inexpensive parametric modeler (for Windows of course) that does a lot of what SOlidWorks does
[02:48:15] <SWPadnos> but it looks a bit like old skool UNIX software
[02:48:24] <SWPadnos> called CadMax, $300
[02:50:06] <L84Supper> i just don't like working with windows anymore
[02:50:18] <SWPadnos> yeah, me either
[02:50:56] <SWPadnos> things like Altera FPGA tools bug me too - free on Windows, $2k for Unix/Linux
[02:51:33] <SWPadnos> and then the boneheads at Altium who, though they make a fantastic electronic design package, use directX instead of openGL for 3D
[02:51:42] <L84Supper> the Xilinx tools are clunky as well on Linux
[02:51:49] <SWPadnos> at least they work though
[02:52:25] <L84Supper> I haven't tried the Altium tools yet, what do you think of them?
[02:52:43] <SWPadnos> they're really excellent
[02:52:56] <L84Supper> whats the $
[02:53:05] <SWPadnos> some library support is sketchy, but of course you can pretty easily design your own components
[02:53:07] <SWPadnos> $10k
[02:53:53] <SWPadnos> does FPGA (but needs vendor tools for place-n-route), C-code to FPGA, pinpart/pin swapping between FPGA and PCB ...
[02:54:07] <L84Supper> Orcad/Cadence fpga integration is clumsy
[02:54:17] <L84Supper> for Xilinx
[02:54:46] <SWPadnos> yeah - Altium is a bit like SolidWorks in the PCB arena - it works very well, has tons of features, and looks nice
[02:55:04] <SWPadnos> doesn't necessarily do a lot more than the other packages, but it's very easy to do some very hard things with it
[02:55:26] <SWPadnos> and also, like SolidWorks, they seem to be stuffed quite a ways up Microsoft's ass
[02:55:53] <L84Supper> we get most schematics in Orcad Capture, layout in allegro
[02:57:06] <SWPadnos> I haven't touched Orcad since the SDT III days
[02:57:13] <SWPadnos> don't plan to unless I have to :)
[02:57:20] <L84Supper> Solidworks does most of the mechanical, the industrial designers prefer pro-e
[02:57:51] <L84Supper> oh it was terrible back then
[02:58:10] <SWPadnos> heh
[02:58:13] <SWPadnos> yes it was
[02:58:13] <eric_unterhausen> I can't stand pro/e
[02:58:45] <L84Supper> I never got used to pro-e
[02:58:47] <eric_unterhausen> I guess it's what you are used to though
[02:59:09] <eric_unterhausen> if nothing else, when it goes and checks for a license it should just do it silently
[02:59:31] <L84Supper> the ID people say it does all the funky curves and forming easier
[02:59:42] <eric_unterhausen> I don't understand why it has to put up a dialog box telling me it no longer trusts me 30 minutes after it checked for the license last time
[02:59:51] <L84Supper> heh
[03:00:49] <SWPadnos> but what if someone else tried to start it up and stole your floating license
[03:01:03] <SWPadnos> you wouldn't want to illegally keep doing your job, would you?
[03:01:05] <eric_unterhausen> then put up the stupid dialog box
[03:01:16] <L84Supper> I haven't reinstalled since I upsized the HD, it didn't think it was installed anymore
[03:01:31] <SWPadnos> I had that problem with CadMAX too
[03:01:45] <SWPadnos> change hard disks or network cards and you're in trouble
[03:01:55] <L84Supper> it much check the ID or size of the HD to build a check for the license manager
[03:02:03] <SWPadnos> like nobody upgrades PCs, ever
[03:02:21] <SWPadnos> serial number a lot of the time, but there are some schemes that put data in unused space on the HD
[03:02:24] <SWPadnos> put
[03:02:30] <JymmmEMC> And thus sw hacking was born
[03:02:39] <L84Supper> :)
[03:02:46] <SWPadnos> (like the rest of cylinder 0, which is often unused)
[03:02:52] <SWPadnos> yeah, no kidding
[03:03:26] <JymmmEMC> Now, jsut shove it in a VM and remove the networking =)
[03:03:27] <SWPadnos> "I will figure out how to use my legally purchased software without having to $TERRIBLE_SCHEME"
[03:03:42] <SWPadnos> soon, soon
[03:03:54] <SWPadnos> I'm expecting a SM3 how-to in a few minutes :)
[03:04:38] <JymmmEMC> "Hey, you a5holes, My engineers are in Alaska you dumb fsck and dont have internet access. Fix this POS!"
[03:04:57] <L84Supper> Linux has all these great 3d modelers and ray tracers, but no 3d CAD
[03:05:01] <JymmmEMC> Thank you and have a nice day
[03:05:42] <JymmmEMC> Stinger Missile 3 ?
[03:05:50] <JymmmEMC> SWPadnos: who did you piss off?
[03:06:01] <SWPadnos> shader model, bonehead!
[03:06:12] <SWPadnos> I mean JymmmEMC
[03:06:41] <JymmmEMC> SWPadnos: What's the toy this years at the show?
[03:06:44] <JymmmEMC> -s
[03:06:48] <SWPadnos> beagleboard
[03:06:56] <SWPadnos> you have to pay extra for it
[03:07:14] <SWPadnos> they still have some Arduinos from last year - I'm sure they're not too happy about that
[03:07:41] <L84Supper> the OMAP is what I was considering a port to of EMC
[03:07:46] <JymmmEMC> how much for the Arduinos?
[03:08:20] <SWPadnos> dunno
[03:08:32] <SWPadnos> I mentioned that I may want a few if they're fast enough
[03:08:48] <L84Supper> the OMAP in the beagleboard has ARM + DSP + GPU
[03:09:03] <SWPadnos> they offered me one when I complained about not getting a pro-rated refund (they cut the conference to 4 days instead of 5)
[03:09:27] <JymmmEMC> those bastards
[03:10:07] <SWPadnos> I paid << half price, so I'm not doing too badly still, but it was annoying
[03:10:43] <SWPadnos> and I had bought a refundable/changeable flight, so I didn't incur any extra costs there (saving a little, since I cut a day off the hotel :) )
[03:10:57] <SWPadnos> so no fun day on Friday, I'm sorry to say
[03:11:09] <SWPadnos> we'll have to hit the Palace BBQ some other time :)
[03:12:14] <SWPadnos> like Sunday the 29th - does that sound good?
[03:16:48] <fenn> L84Supper: if you want to help get the linux 3d cad off the ground, help work on HeeksCAD
[03:16:55] <fenn> http://heekscad.googlecode.com/
[03:17:48] <L84Supper> looks interesting
[03:18:44] <fenn> this is something i made the other day
[03:18:50] <fenn> http://fenn.freeshell.org/motor_mount.png
[03:21:29] <Optic> hmm
[03:24:55] <L84Supper> http://pastebin.ca/1361217 Wine with DirectX 9.0c Pixel Shader 3.0+
[03:25:06] <SWPadnos> cool, thanks
[03:25:25] <L84Supper> contact him with any issues
[03:25:32] <SWPadnos> will do, thanks again
[03:28:39] <L84Supper> I should get him a paypal account :)
[03:28:46] <SWPadnos> heh
[03:33:08] <L84Supper> did anyone ever get the Lego NXT stuff going with Linux?
[03:45:54] <eric_unterhausen> I rode my bike on a 70 mile ride known as the "7 climbs of death"
[04:31:48] <toastydeath_> I think it is amazing that blackberry has an irc client
[05:58:06] <KimK> Speaking of different CAD packages, I recently discovered VeriCAD http://www.varicad.com/ it has Windows and Linux versions. Has anyone here used it or tried it? Or heard anything about it?
[06:03:55] <UncleGemc> Im working on a bridgeport mill conversion. Could I uses the pre-existing DRO glass slides as a good encoder setup vs a on motor rotary encoder?
[06:05:02] <eric_unterhausen> why not?
[06:05:14] <UncleGemc> yeah that was my question
[06:05:16] <UncleGemc> :)
[06:05:42] <eric_unterhausen> you can do that, no problem
[06:06:00] <UncleGemc> Seems to me it would be better considering I would have to worry about play anywhere in the system since the reading is coming directly off of the linear slide.
[06:06:35] <UncleGemc> wouldnt* have to worry about the play
[06:07:06] <eric_unterhausen> depends on how much play you don't want to worry about, but it should help
[06:07:59] <UncleGemc> i mean if there is some play in the screws that wouldnt really show up on since the slide is where the reading is coming from
[06:08:27] <UncleGemc> However, it may cause the slide to jitter on heavy cut regardless
[06:09:13] <UncleGemc> Also, in theory I wouldnt really have to mathematically figure out the ratios and screw pitch for anything
[06:09:37] <eric_unterhausen> you have analog command servos?
[06:09:51] <UncleGemc> yeah (im guessing)
[06:10:01] <UncleGemc> +/- 10v
[06:10:15] <UncleGemc> Dac amp copley controls amp cards
[06:15:51] <UncleGemc> eric_unterhausen: what kind of setup do you have?
[06:23:04] <eric_unterhausen> analog servo using motor encoders for feedback
[06:23:50] <UncleGemc> Do you have any photos of your system?
[06:24:13] <UncleGemc> specs ect
[06:25:13] <eric_unterhausen> it's on cnczone
[06:25:22] <eric_unterhausen> I gotta go to be thoug
[06:25:23] <eric_unterhausen> h
[06:25:35] <fenn> if you can't figure out the screw ratio you have no business messing with linear encoders
[06:25:53] <UncleGemc> later man
[06:26:07] <eric_unterhausen> gnite, I'll find the link next time
[06:26:13] <UncleGemc> np seeya round
[06:27:07] <UncleGemc> Its not a matter of being able to do math, its a matter of why do it if I dont have to as well as pay 180 for two new rotary encoder when I already have 2 linear encoders installed
[06:28:45] <fenn> because you need some form of velocity feedback from the motor
[06:29:25] <fenn> or they will buzz like mad from the play or stretch in the system
[06:30:03] <UncleGemc> I see
[06:31:40] <UncleGemc> What outputs the velocity, just the A/B phase of the encoders?
[06:32:05] <fenn> the linear encoder is much lower resolution, so you get very coarse velocity info from the position ticks
[06:32:51] <UncleGemc> isn't that dependant on the quality of the encoder?
[06:32:52] <fenn> in the 80's they made a lot of systems with glass scales and tachometers, which are little DC generators attached to the back of the motor (voltage proportional to speed)
[06:33:03] <UncleGemc> which im using
[06:33:12] <UncleGemc> All my motors have tachs.
[06:33:22] <fenn> you could use a super high resolution scale but why?
[06:34:16] <UncleGemc> While running my motor without load and with the rotary encoder the vibration/hum is basically gone
[06:34:32] <KimK> I have run servos with just a hi res linear encoder with good results. Max velocity was a little lower then "usual", what, maybe 100 or 200 FPM? Lower due to "speed limit" of hi-res encoder, as I recall. Not bad though.
[06:35:08] <UncleGemc> L
[06:35:54] <UncleGemc> KimK: are you saying there should be little problem with buzz/humm/vibration in the motors you used when you used linear encoders?
[06:36:27] <UncleGemc> Like fenn mentioned I really don't want bad buzzing in my motors 24/7
[06:39:57] <KimK> Well, we did not have any servo tuning / feedback / type-problems of that sort, but we were using induction motors and vector drives, so running on AC. And in a loud industrial environment.
[06:40:28] <KimK> We must have come in to run them on a weekend, though, and I don't recall hearing any unusual noises when things were quieter.
[06:43:21] <KimK> There should be something in the wiki about the advantages of running two encoders though. As I recall, the hi-res encoder goes to the "I" term of the PID and promotes more accurate final settling. Maybe the rotary encoder removes the speed limit so the hi-res linear encoder doesn't get "lost" at hi speeds?
[06:44:01] <KimK> No, I'll bet not. If it gets lost, it gets lost.
[06:44:07] <KimK> Lost is lost
[06:45:09] <UncleGemc> I'll just have to do some testing with what I have at hand if all else fails I will go back and use rotary encoders
[06:45:45] <KimK> I'm always glad when I get to use a Bridgeport that has a DRO, versus one that doesn't, though
[06:46:01] <UncleGemc> KimK: I run a screw machine shop, Acme gridley 6 spindles and davenport 5 spindle bar feeders, What do you specialize in?
[06:48:04] <KimK> I do assorted electronic and motion control stuff, sometimes a little simple machining. Working on some EMC2 retrofits. I've done non-EMC2 retrofits in the past. Looking forward to seeing EMC2 work.
[06:48:32] <fenn> the idea is the linear encoder doesn't need to be so high rez
[06:52:23] <KimK> In my case, the linear encoder we were using had an optional converter box that put out the usual A/!A, B/!B, Z/!Z. So (as that button in the commercial says) Easy!
[06:52:25] <UncleGemc> Well, fenn I suppose I'll just see what I get and go from there, I still have a lot to learn so i'll be messing around with thi stuff for awhile.
[06:53:19] <UncleGemc> Do you have a ny photos or specs on your setups fenn?
[06:53:37] <KimK> The HALscope should make tuning easy, when you get to that point
[06:53:58] <fenn> UncleGemc: eh i haven't dont anything substantial with servos yet
[06:54:32] <fenn> http://fenn.freeshell.org/portfolio/DCP_0785.JPG
[06:54:53] <fenn> that's a pancake servo from a copy machine
[06:55:25] <UncleGemc> yeah, me either I just got a couple running like bats out of hell on my desk here, I am in the process of building the conversion block for the mill and also a yx table to do profiles on my index werke single bar feeder
[06:55:37] <KimK> Hah, is that a plexiglas/perspex motor mount?
[06:56:02] <KimK> The "floating" motor, LOL
[06:56:30] <KimK> Hey, if it works, I can't knock it!
[06:57:15] <UncleGemc> pretty sharp
[06:57:40] <UncleGemc> what is the machine it's self?
[06:59:58] <UncleGemc> from this POV it looks like a very basic lathe
[07:00:25] <KimK> UncleGemc: While we're waiting for fenn, what city are you in, and how has business been lately? And since you mention screw machines, how long does it take you to changeover? Or do you never change?
[07:01:34] <fenn> it's polycarbonate, 3/8" or so
[07:01:38] <fenn> i had a bunch of it lying around
[07:01:59] <UncleGemc> Huntington, IN north of Indianapolis and south of fort wayne. Depending on complexity of the part a achanger can take anywhere from 2 hours to 16 hours and average of 8 hours in most cases
[07:02:30] <fenn> the machine is a gingery lathe, somewhat modified from the original plans
[07:02:55] <KimK> UncleGemc: OK, I had heard changeover on a screw machine was a big deal, just curious.
[07:03:08] <UncleGemc> This reason is why I considered getting into CNC on my single barloader, I can do a fast setup for prototype/sample parts and short run jobs without taking two work days to complete
[07:03:13] <KimK> fenn: welcome back, thanks for the pic
[07:04:07] <fenn> my original idea was to do lost foam cast aluminum for the motor mounts, but i had to give the CNC foam cutter back to its builder
[07:04:23] <fenn> and the cam software available wasn't up to what I wanted
[07:05:05] <UncleGemc> seems to me it would be easier/cheaper to buy a small hardinge at auction and do a conversion that way
[07:05:41] <fenn> you should get a HNC - that way it's basically done already
[07:06:43] <UncleGemc> http://www.pulleys.com/hardinge6station.jpg
[07:06:47] <fenn> http://www.wallacecompany.com/cnc_lathe/HNC/
[07:06:54] <UncleGemc> Thats what I was referring to
[07:07:07] <fenn> look at the size of that crank pulley
[07:08:12] <fenn> i wonder what all that electrical stuff is on kirk wallace's lathe
[07:09:10] <fenn> VFD for the coolant pump??
[07:09:46] <fenn> oiler relay and timer fuses?
[07:10:48] <UncleGemc> looks like a lot of overkill to me.
[07:10:59] <UncleGemc> maybe he just has money to spend
[07:13:18] <KimK> fenn: re: cast aluminum, interesting, what kind of foam is it OK to "lose", without (possibly) releasing aluminum-unfriendly gases? acids? etc? Does about any foam work?
[07:18:14] <KimK> On the coolant pump VFD, I can see a use for that. Recently I was using a machine with a strong coolant pump, I had to turn the stop valves almost all the way closed (99%?) to stop excessive splashing.
[07:19:23] <KimK> So that was OK for a while, but then slowly, slowly, the valve openings clogged, and the coolant dropped off. So every so often, I had to open the valves and then close them again.
[07:20:30] <KimK> A VFD would let you keep the large (non-cloggable) valve opening, but reduce the flow as needed. So I vote nice feature.
[07:20:45] <fenn> KimK: the most environmentally friendly is plain white styrofoam; i use blue house insulation because it has a fine grain structure for good surface finish, but it gives off some flame retardant stuff which stinks
[07:20:58] <fenn> don't use "great stuff" though because it gives off cyanide
[07:21:38] <UncleGemc> just putting a secondary coolant output valve back to the pump resivoir would do the same thing though
[07:21:45] <UncleGemc> couple bucks..
[07:22:07] <UncleGemc> thats I how I do my pumps on my crossdrilling machine.
[07:23:40] <KimK> fenn: OK, thanks, I'll keep that (those) in mind. If I was heating aluminum, I would likely be heating it in the great outdoors, but still, you can't be too careful.
[07:24:32] <KimK> UncleGemc: Say, that sounds like it would work too, I'll give it some thought
[07:28:26] <UncleGemc> KimK: you see, im kinda old school and used to mainly mechanics so I seem to find workarounds without electronics before anything else
[07:29:06] <UncleGemc> I gotta admit though, there are some pretty amazing things I can accomplish with this cnc business
[07:29:49] <KimK> Hey, no problem, whatever is the easiest and cheapest to get working. Especially in the present economy.
[07:30:20] <UncleGemc> building a cnc profiling attachement for my single barloader will saves tons on form tools since they need to be edm'd and ground all the time, where the profiler can be just a simple carbide lathe tool
[07:30:26] <UncleGemc> werd :P
[07:31:13] <UncleGemc> especially with sample parts and prototyping, I dont want to spend a couple hundred on tooling just to make 5 parts.
[07:31:36] <KimK> Speaking of cheapest (compared to AutoCAD or SolidWorks) Have you guys ever run across VariCAD? I asked this earlier, sorry if you saw it already. Or how about HeeksCAD or HeeksCAM, ever played with those?
[07:33:48] <KimK> I like Qcad because it's free on Ubuntu, but it's only 2D and is pretty basic. I miss TurboCAD Pro on Windows, but hope not to go back to the dark side. VariCAD looks promising.
[07:35:52] <UncleGemc> I tried using the dxf to gcode converter but I cant seem to get it to work
[07:35:57] <UncleGemc> anyone else mess with it?
[07:36:18] <UncleGemc> from my experience it just would output a blank file
[07:36:28] <KimK> BTW, there is a Windows version of Qcad (the "Community Edition", free and unlimited) on SourceForge. They don't advertise it much on the web, but it's there.
[07:38:24] <KimK> You mean dxf2gcode? Yes, I tried it, I got way more than nothing, but it was kind of confusing mess. I used some of it by copying and pasting blocks that I recognized. Other parts I just filled in by hand. So, not a rousing success for me.
[07:38:44] <UncleGemc> hrmm
[07:39:00] <UncleGemc> yes that was the program but like I said I just got fail :P
[07:39:08] <UncleGemc> I will have to look back into it
[07:40:07] <KimK> Did you feed it the DXF from Qcad? And did you make use of layers at all? I think layers help, but I can't really say from one test.
[07:41:36] <UncleGemc> it may not have been from qcad, it was a dxf I got off the web
[07:41:49] <KimK> OK
[07:45:56] <UncleGemc> :( got D/C did I miss anything?
[07:47:12] <KimK> Not a thing, I was looking up something. And here it is: The download page on that Windows free-non-demo Qcad: http://sourceforge.net/project/showfiles.php?group_id=240145
[07:48:35] <KimK> It's a totally manual install, you have to create a folder under "Program Files", and then make a shortcut to it in the Start Menu. The upside is, it doesn't monkey with the registry or anything.
[07:49:05] <KimK> To uninstall, just delete everything manually.
[07:50:03] <UncleGemc> yeh, I dont really use windows much so..
[07:50:05] <UncleGemc> :P
[07:50:29] <UncleGemc> I did btw just get that converter to spit out a simple file I made in qcad to work.
[07:51:50] <KimK> Yeah, I'm trying to avoid Windows too, but useful free apps (Firefox, OpenOffice, etc.) are great ways to lead users to Linux, and make them feel more at home when they get there.
[07:52:02] <UncleGemc> true
[07:52:08] <UncleGemc> thats how I did my g/f
[07:52:34] <KimK> You got dxf2gcode to work? Great! What did the result look like?
[07:53:17] <KimK> Was it what you expected?
[07:56:20] <UncleGemc> LOOKED LIKE WHAT i EXPECTED :)
[07:56:53] <KimK> I hate it when I bump caps lock, lol
[07:58:23] <UncleGemc> yeh :P
[07:58:57] <UncleGemc> I actually left it on from when I was editing the gcode file getting rid of the z axis
[08:00:49] <KimK> Your machine wants caps? Yeah, probably most do. Nice that EMC2 takes either case.
[08:04:43] <KimK> Well, UncleGemc , fenn , thanks for the chat. I'm going to call it a night.
[08:45:55] <MrSunshine_> what is preferably used for steppers, fast, slow or mixed mode decay?
[13:32:31] <tomp> if you take a step in x&y, you move further than if just in X (1.414... and ad nauseum for xyz xyzw etc motions).
[13:32:37] <tomp> So, the velocity would increase if the step rate was constant ( constant step freq but varying step lengths).
[13:32:38] <tomp> Does emc check the velocity on a step by step basis, or a longer time interval?
[13:32:55] <tomp> we ran across this in the 80's on AGie wire edms (2d systems)
[13:34:32] <SWPadnos> emc doesn't deal with steps at hte planning level, it deals with position changes over a fixed period (the servo period)
[13:34:53] <SWPadnos> it's impossible to move less than one step
[13:35:30] <tomp> huh, what about less than 1 step? the dist traveled in XY motion is 1.414 the unit size
[13:35:36] <SWPadnos> so if you choose a step size that's large enough to make a difference whether you're moving X, XY, or XYZ, then you have an inappropriate step size
[13:36:36] <SWPadnos> in all likelihood, the steps on XYZ will not be at the same instant, unless they're all going full speed (not likely in EDM)
[13:36:59] <SWPadnos> so you end up with a zig-zag, and slightly varying speed
[13:37:25] <tomp> i must be unclear, the distance moved is greater in a multi axis step, than in a single axis step. if the step rate is constant, the velocity is not constant
[13:37:38] <SWPadnos> yep, I agree
[13:38:02] <SWPadnos> you asked (I thought) if EMC takes this into account. the answer is no - not at that level
[13:38:07] <tomp> k
[13:38:08] <tomp> thx
[13:38:28] <SWPadnos> EMC asks for a velocity, which is decomposed into joint velocities, which are accomplished by stepgen (for steppers)
[13:38:29] <tomp> what are you doing up? on the road?
[13:38:40] <SWPadnos> no, I'm getting ready to go out to breakfast with my wife :)
[13:39:08] <tomp> ummmm american breakfasts (drool)
[13:39:08] <SWPadnos> it's almost 10:00 - you have to get out relatively early to aboid the college crowd
[13:39:18] <SWPadnos> best eggs benedict in the world IMO
[13:39:40] <SWPadnos> (and I've tried a lot of eggs benedict, in ~15 time zones)
[13:39:49] <tomp> oh, and you're in maple syrup land too
[13:39:57] <SWPadnos> yep
[13:40:05] <tomp> waah!
[13:40:08] <SWPadnos> hmmm. maybe a waflle too :)
[13:40:37] <SWPadnos> hey - they're online: http://www.sneakersbistro.com/
[13:41:05] <SWPadnos> way back when it used to be a jazz bar that started to serve breakfast
[13:41:10] <SWPadnos> now they only do breakfast :)
[13:41:33] <SWPadnos> time to run. catch you later
[13:41:56] <tomp> enjoy, bye
[13:58:41] <DanielFalck> hi tomp
[14:02:04] <tomp> hi Dan, how are you
[14:02:19] <DanielFalck> doing well. Are you still across the ocean?
[14:02:36] <tomp> yeh, looks like another month, got nice digs tho
[14:02:48] <DanielFalck> that's good
[14:03:31] <tomp> we got 5 axis up running & incredibly sweet. sounds like real servos should ( squeek, whiz, chirp )
[14:03:33] <tomp> :)
[14:03:53] <DanielFalck> what kind of machine?
[14:03:58] <DanielFalck> edm?
[14:04:01] <tomp> custom 7 axis edm
[14:04:50] <tomp> i have the spanish cnc developer here with me, between him & the taiwanese, i go nuts
[14:06:18] <tomp> whats new in the usa? did obama make a difference? everyone her is dissapointed he wasnt the messiah
[14:06:49] <DanielFalck> I've been too busy to notice yet. We're making bike parts as fast as we can here.
[14:07:06] <DanielFalck> we started doing bike frames too
[14:07:26] <tomp> biking is big here, really hi-end shops. people throw big buck around
[14:07:38] <DanielFalck> http://cielo.chrisking.com/
[14:08:00] <tomp> i loved to watch brits sweat frames together with italian joints
[14:08:26] <DanielFalck> the drop outs, seat stays, fork crowns, head badges, heat tube collars, etc are some of my work
[14:08:43] <DanielFalck> head tube...
[14:08:50] <tomp> forged?
[14:08:55] <DanielFalck> all milled
[14:09:01] <tomp> wow nice
[14:09:07] <DanielFalck> out of 17-4 stainless
[14:09:39] <DanielFalck> http://www.velonews.com/photo/88700
[14:10:57] <DanielFalck> HeeksCAD/CNC is coming along nicely now
[14:11:07] <DanielFalck> pocketing is working very well
[14:11:21] <DanielFalck> I did some engraving in my home shop with it last night
[14:11:35] <tomp> the pix are great, i dunno Heeks
[14:11:44] <DanielFalck> http://imagebin.org/41383
[14:12:00] <DanielFalck> http://code.google.com/p/heekscnc/
[14:12:17] <DanielFalck> his work is split up into different modules
[14:12:34] <DanielFalck> http://code.google.com/p/heekscnc/wiki/Capabilities
[14:13:12] <tomp> hey i cant look that fast! you a busy guy ! :)
[14:13:17] <DanielFalck> even brent of apt360 fame is checking heekscnc out
[14:13:24] <anonimasu> :)
[14:13:39] <DanielFalck> we still hang out in #cam
[14:13:49] <tomp> i've not been on #cam for a while...
[14:31:46] <steves_logging> steves_logging is now known as steve_stallings
[14:41:13] <MrSunshine> i dont et it, what the heck should PFD be ? :) anyone know ? ... i have a pot on now but i cant figure out what the max voltage in on it is
[14:41:33] <MrSunshine> pfdh = 0.6xVDD, pfdl = 0.21xVDD
[14:43:21] <MrSunshine> should i just set it to mixed and be happy with that? :)
[14:58:51] <alex_joni> Personal Flotation Device ?
[14:59:00] <alex_joni> http://www.kayakonline.com/pfds.html
[16:14:39] <MrSunshine> alex_joni: setting for decay mode
[17:47:13] <anonimasu> anyone here have a good idea about oxyfuel cutting?
[17:47:57] <alex_joni> what do you mean by "good idea" ?
[17:48:28] <anonimasu> abouit how piercing works
[17:49:19] <alex_joni> slowly ;)
[17:49:27] <anonimasu> haha
[17:49:34] <alex_joni> and with lots of backspatter
[17:49:47] <anonimasu> yeah, that's what im wondering
[17:50:00] <anonimasu> do you just preheat lots then go down with the torch to cutting depth?
[17:50:06] <anonimasu> after turning on the cutting gas?
[17:50:29] <alex_joni> you need to do some pecking cycles
[17:50:29] <anonimasu> http://www.io23.net/ul/files/IMAGE_217.jpg
[17:50:50] <alex_joni> ah, thin stuff?
[17:51:00] <anonimasu> and thicker stuff too
[17:51:07] <anonimasu> http://www.io23.net/ul/files/IMAGE_218.jpg
[17:51:16] <anonimasu> http://www.io23.net/ul/files/IMAGE_213.jpg
[17:51:54] <alex_joni> thin enough ;)
[17:52:03] <alex_joni> you get issues if you pierce with more than 40mm
[17:52:12] <anonimasu> I see
[17:52:29] <anonimasu> and how do you do it?
[17:52:36] <anonimasu> like call up a peck cycle?
[17:53:10] <alex_joni> something like that
[17:53:15] <anonimasu> or hm..
[17:53:21] <anonimasu> I were hoping to avoid it :)
[17:53:31] <anonimasu> I have a motor but no controlled Z
[17:53:42] <anonimasu> other then a thc that should arrive soon
[17:54:57] <anonimasu> and that just moves Z to make it keep a constant height with some relay outputs
[18:00:22] <anonimasu> alex_joni: any ideas?
[18:03:43] <alex_joni> cut from the side of the sheet ;)
[18:03:55] <alex_joni> or use a drill to predrill insteead of piercing
[18:04:10] <alex_joni> at least that's how I've seen it's done on thicker stuff
[18:04:21] <anonimasu> but for <40mm stucc
[18:04:23] <anonimasu> stuff..
[18:04:31] <alex_joni> for that you could probably do it
[18:05:51] <anonimasu> im looking for options how to make it work with my setup.. like peck cycle, but without a fully controlled axis..
[18:07:00] <alex_joni> basicly you need to move up/down a couple times
[18:07:11] <alex_joni> not necessarely in a controlled manner
[18:08:25] <anonimasu> well, I can move my axis down to the cut height..
[18:08:41] <anonimasu> and run it up, for 2 seconds and pierce
[18:08:48] <anonimasu> and move it down to the cut height and repeat
[18:09:02] <alex_joni> yup, that might get you closer
[18:09:23] <alex_joni> try doing it by hand a couple times, till you find a good setting to do it
[18:09:38] <anonimasu> yeah, as soon as the thc arrives :)
[18:09:56] <alex_joni> I meant by hand
[18:10:01] <alex_joni> holding the torch
[18:10:05] <alex_joni> with your hand
[18:11:05] <anonimasu> * anonimasu nods
[18:11:57] <anonimasu> bbl
[19:56:35] <dpy> hey guys
[19:57:02] <dpy> say, does anyone here have experience with casting timing belt pulleys?
[19:57:43] <dpy> I've looked around a bit and these pulleys are very expensive
[20:20:47] <giacus> hello
[20:21:42] <giacus> do you want a sandwiches ?
[20:21:50] <giacus> http://www.youtube.com/watch?v=lQOkMz3kiS0
[20:21:52] <giacus> :D
[20:23:12] <giacus> bye guys..
[20:23:23] <the_goat> that was odd
[20:23:35] <the_goat> but I do want a sandwich
[20:26:16] <alex_joni> horrible machine
[20:26:33] <fenn> dpy: i think you'd have to hob them like a gear
[20:26:52] <fenn> dpy: are you doing XL or MXL or what?
[20:51:54] <dpy> fenn: this is for MXL
[20:52:12] <dpy> what is "to hob them like a gear" ?
[20:52:16] <dpy> "to hob"
[20:53:00] <alex_joni> dpy: http://en.wikipedia.org/wiki/Hobbing_machine
[20:54:31] <dpy> yes of course, that is the standard way of doing it
[20:54:56] <dpy> my point is: can't you take an existing gear, make a mold out of it
[20:55:03] <dpy> and resin cast a new one
[20:55:15] <dpy> for MXL the gears are fairly small and lightweight
[20:55:41] <dpy> meaning, the resin/mold supply costs are low
[20:56:05] <fenn> oh, resin cast yeah
[20:56:05] <dpy> lower than buying a couple of these at sdp/si or one of the european companies
[20:56:12] <fenn> i was thinking sand casting aluminum or something
[20:56:18] <dpy> no no
[20:57:02] <dpy> but I figure, I'm the only thinking of doing it
[20:57:13] <fenn> i think i'd rather figure out how to set up a way to make them properly, then i can make any size i like
[20:57:48] <dpy> properly means a 2000+ machine
[20:57:56] <fenn> whatever
[20:58:02] <fenn> you're just not thinking
[20:59:09] <fenn> http://www.americanmachinetools.com/How_to_use_a_Milling_Machine_files/Fig8-34.gif
[20:59:11] <fenn> single point gear cutter
[21:00:07] <alex_joni> good night all
[22:15:30] <Optic> moo