#emc | Logs for 2008-03-06

[00:00:43] <lerman> There's been a bunch of recent email on the list about restart in the middle of a program.
[00:01:13] <lerman> Has there been a feature request for (a decent way to do) this?
[00:01:29] <lerman> Does anyone want to put together a spec for it?
[00:01:31] <archivist> * archivist was just reading that, I have a need
[00:02:05] <lerman> In that case, would you care to volunteer to put together a feature request in SourceForge?
[00:02:54] <lerman> An alternative would be to generate something in the wiki so that "everyone" could comment/enhance it.
[00:03:10] <archivist> mine may be a mod on what others need as its a measure, cut, measure.... then continue
[00:03:46] <lerman> In the presence of o-words and looping, the problem is much more complicated than just selecting a line of code.
[00:04:21] <lerman> Questions: continue implies that we stopped. How did we stop? estop? pause? other?
[00:04:28] <archivist> Im currently having "fun" as I dont have exact sizes for cutters and so dont know depth of cut needed
[00:05:04] <lerman> After the stop, estop, pause, what can we do? Is MDI active? Jogging? Homing?
[00:07:46] <archivist> currently I stop check, jog x thou, set new offset, and rerun till close, do full cycle, measure, jog, reset offset, run one last time to size
[00:08:27] <archivist> gear milliing by the way for clock gears
[00:10:12] <archivist> I cant decide yet the best way forward, currently experimenting with a camera on the machine to help
[00:57:06] <SWPadnos> lerman, even the simple scenario you mentioned has multiple use cases
[00:57:13] <SWPadnos> what about tool compensation?
[00:57:29] <lerman> Yup.
[00:57:47] <lerman> Tool length AND diameter.
[00:57:59] <SWPadnos> there are a couple of ways of dealing with that (edit tool table, be sure the new comp is read in)
[00:58:20] <SWPadnos> the other way is use G43.1 and G41 R-- to specify the new numbers, and *don't* read the table ...
[00:58:27] <SWPadnos> yes, both - even better :)
[00:58:57] <SWPadnos> also, spindle speed and possibly feedrate may need to be changed (though that's a bigger issue, and can probably be avoided using FO and SO)
[00:59:11] <lerman> I think part of the solution will involve the ability to do things when "stopped". Jog and MDI come to mind.
[00:59:24] <SWPadnos> yes, which currently can't be done
[00:59:30] <SWPadnos> unless you stop, vs. pause
[00:59:34] <lerman> Within MDI, the ability to call an existing subroutine would be a big help.
[01:00:03] <lerman> All of that should be "fixed".
[01:00:11] <SWPadnos> I guess most scenarios can be handled if there are two types of restart: one that restores state and one that doesn't
[01:00:30] <SWPadnos> of course, all that state stuff would have to be left alone on a transition to run mode from MDI/manual mode
[01:00:56] <lerman> stop, pause, estop, should all do similar things. Don't throw away the state. The type of restart will determine what is thrown away.
[01:00:59] <SWPadnos> did you ever add the feature that looks for subroutines "somewhere"
[01:01:08] <SWPadnos> hmmm.
[01:01:10] <lerman> Yes.
[01:01:19] <SWPadnos> cool
[01:01:21] <lerman> I forget precisely where.
[01:01:26] <lerman> :-(
[01:01:37] <SWPadnos> spindle is part of the state, and that should certainly be stopped on estop, and probably some others as well
[01:01:38] <eric_U> maybe you should have a routine that looks for it
[01:01:39] <SWPadnos> heh
[01:01:49] <lerman> In the long run, a list of places should be supplied in the .ini file
[01:01:54] <SWPadnos> nc_files_dir/subroutines would be a good place ;)
[01:01:59] <SWPadnos> sure
[01:02:40] <lerman> On my list of things to do is allow user defined gcodes. That will also need to have a place to look for them.
[01:03:17] <SWPadnos> indeed
[01:03:25] <lerman> The thought of someone modifying the code to add a favorite canned cycle drives me crazy.
[01:03:25] <JymmmEMC> echo Tuscon\nEl Paso\nNew York City\n > subroutines.ini
[01:03:28] <SWPadnos> nc_files_dir/macros :)
[01:03:52] <lerman> Canned cycles can all be built from existing gcodes.
[01:04:14] <lerman> The "integrator" should specify that stuff in the .ini
[01:04:14] <SWPadnos> echo "New York, London, Paris, Munich" > Pop_Music
[01:04:41] <lerman> I saw a thread somewhere about machine tools playing music.
[01:04:48] <SWPadnos> JymmmEMC, that would be an "M" code ;)
[01:04:59] <lerman> My first thought was that someone was moving the servos in such a way to play a tune.
[01:05:09] <SWPadnos> yes, a 4-axis EMC2/stepper machine can play "daisy"
[01:05:10] <lerman> as to play a tune.
[01:05:12] <JymmmEMC> SWPadnos: I much prefer CAM tyvm
[01:05:16] <SWPadnos> there are subroutines to output notes on steppers
[01:05:55] <SWPadnos> http://en.wikipedia.org/wiki/Pop_Muzik
[01:08:00] <SWPadnos> I guess I had mis-spelled "muzik" :)
[01:19:00] <skunkworks> http://youtube.com/watch?v=R26yo7P9mwA
[01:22:16] <lerman> skunkworks: Nice.
[01:27:38] <lerman> Does anyone here know who added the "repeat" type o-word to the interpreter?
[01:29:53] <SWPadnos> cradek, I believe
[01:35:54] <skunkworks> does this sound right?
[01:35:56] <skunkworks> http://cnczone.com/forums/showthread.php?p=420662#post420662
[01:53:41] <SWPadnos> skunkworks, yes, that looks right, but there could be a confusion (as always) between lines and cycles per revolution
[01:54:44] <SWPadnos> astually, your formulas explicitly mention the x4 factor, so maybe the only confusion is mine :)
[01:56:56] <skunkworks> heh
[01:57:52] <skunkworks> Thanks
[01:58:27] <SWPadnos> I'm not sure you needa full "x2" factor in there, but it probably doesn't hurt to tell pwople you do :)
[01:58:31] <SWPadnos> gah
[01:58:46] <SWPadnos> better to type when there isn't a plate of food between you and the keyboard
[01:59:55] <skunkworks> heh - I Know - I was counting close to the base period - but I got the impression I was playing with fire :)
[02:00:16] <SWPadnos> yeah. the calculation is probably based on BASE_PERIOD + max_latency
[02:00:20] <skunkworks> That is why I said - to be safe..
[02:00:27] <SWPadnos> but 2x should guarantee that it works, so it's not a bad thing
[02:01:02] <skunkworks> and who is going to thread at 1500 rpm... ;)
[02:01:32] <SWPadnos> people making 0000-128 threads?
[02:01:39] <SWPadnos> or -256 or something
[02:01:58] <SWPadnos> but cradek would know a lot more than me about that kind of thing :)
[02:16:47] <skunkworks> jmkasunich: could you post the program you used to make your fusee?
[02:21:29] <cradek> lerman: repeat is definitely my fault
[02:21:43] <cradek> skunkworks: that's a nice video of daisy. I'm glad people like it.
[02:23:36] <skunkworks> cradek: I would love to hear what it is like with all 4 axis running
[02:23:46] <skunkworks> It sounds cool as is
[02:24:50] <cradek> skunkworks: oh was that only 3? it sounded quite decent
[02:26:15] <skunkworks> I assumed.. I could be wrong..
[02:29:17] <cradek> * cradek hides from lerman
[02:31:09] <skunkworks> heh :)
[02:32:28] <SWPadnos> repeat 10 Ohide_cradek_from_lerman
[02:33:31] <cradek> (I bet he found a case where it doesn't work right)
[02:34:28] <SWPadnos> heh
[02:34:28] <skunkworks> Why the negativity? Maybe he was going to praise you.. :)
[02:34:41] <cradek> oh right :-)
[02:34:50] <SWPadnos> well, either that or he wanted to thank you for a very useful feature, and commend your coding style
[02:34:55] <SWPadnos> heh
[02:34:59] <cradek> haha
[02:35:28] <SWPadnos> and then drop all the interpreter stuff in your lap, because he's moving to Bermuda
[02:39:52] <cradek> then I would declare it complete
[02:40:04] <SWPadnos> done!
[02:40:11] <cradek> actually it seems like I'm the one who screws with it the most lately
[02:40:30] <cradek> for better or worse
[02:41:33] <cradek> darn, from what you guys were saying earlier I was hoping to see a new jmk blog entry
[02:41:44] <SWPadnos> hmmm. no phone calls from my HAL customer today. either things worked well or he's still busy installing
[02:42:03] <SWPadnos> I think jmk said he'd try to make a video this weekend
[02:42:08] <SWPadnos> I think he's still on the road
[02:42:18] <cradek> I can't wait
[02:42:30] <skunkworks> I love emc.. http://cnczone.com/forums/showthread.php?p=420683#post420683
[02:43:58] <gene> Hello guys
[02:44:32] <skunkworks> Hi
[02:45:04] <gene> I think I don't understand the a axis, or I've found an insect
[02:45:18] <cradek> could be both, gene
[02:46:13] <gene> g1 f45 a-360 turns the table one rev in about 8 minutes, while the bit is plowing a groove to make a 4" diameter plate
[02:46:49] <cradek> sounds right so far
[02:47:28] <gene> I'm going down .025 per rev, so I thought I'd just have it turn the table about 18 times while z went down to -.5"
[02:47:59] <gene> something like g1 f45 a-5900 z-.5
[02:48:22] <gene> and the table took of at aqbout 2 rpm!
[02:48:32] <gene> and the table took off at about 2 rpm!
[02:48:35] <SWPadnos> heh
[02:48:53] <cradek> that's because the meaning of F changes when you move linear + rotary. it's described very carefully in the manual.
[02:48:54] <SWPadnos> combined moves always use inverse time for the angualr axes
[02:48:57] <gene> didn't wreck anything though :)
[02:49:04] <cradek> you should probably use inverse time feed mode
[02:49:13] <cradek> SWPadnos: that's not right
[02:49:26] <cradek> well maybe I don't know what you meant
[02:49:29] <SWPadnos> well, it's an oversimplification
[02:49:40] <gene> gee, you mean i have to read the book again? :-)
[02:49:40] <cradek> let me see if I can find you the url gene
[02:49:59] <SWPadnos> the time to do the XYZ cartesian is used as the time for the angular part, which essentially runs in inverse time mode with that calculated time
[02:50:18] <cradek> http://www.linuxcnc.org/docview/html//gcode_main.html#sub:Feed-Rate
[02:50:27] <lerman> cradek: You did a good job, it seems. It took me a while to be sure the code wasn't mine. :-)
[02:50:46] <gene> oh oh, I must have missed class that dat 70 yearsago...
[02:50:49] <lerman> good night all.
[02:51:04] <cradek> lerman: cool, glad you like it. I saved the count at the beginning so it wouldn't change if the evaluation changes during the repeat.
[02:51:19] <cradek> goodnight ken
[02:51:29] <gene> oh oh, I must have missed class that day 70 years ago... keyboard full of swarf :(
[02:52:06] <cradek> gene: I recommend inverse time mode (G93) for your combined move
[02:52:46] <cradek> for an 8 minute move, you'd program G93 F.125 G1 A... Z...
[02:53:20] <cradek> .125 being 1/8 of course
[02:54:39] <gene> wekk, i copy pasted to do it all in individual moves. I'll go look that up, ahh thanks. what i really need is a coolant system and i could let-r-rip without too much smoke from a dull end mill :)
[02:55:21] <SWPadnos> you could also just use g1 f0.0625 a-5900 z-.5
[02:55:39] <SWPadnos> that would move 1/2 inch at 1/16 inch/minute, taking 8 minutes to complete the move
[02:56:00] <cradek> if Z is moving slowly compared to A, the feeds get more and more silly if you don't use G93
[02:56:10] <SWPadnos> that's certainly true :)
[02:56:19] <gene> i figure it will be done about the time my feet are frozen solid, damn this diabetis
[02:56:25] <cradek> I think G93 is really the best way here, but it's true you can get by without
[02:56:45] <cradek> gene: it's too cold in March for unheated shops!
[02:56:50] <SWPadnos> G93 F[1/8] G1 A... Z...
[02:57:10] <SWPadnos> even less brainpower needed
[02:57:33] <gene> its about half done now. cute steve
[02:57:52] <cradek> I've met steve; he's just average looking
[02:58:02] <SWPadnos> there is a cute steve too, I'm sure
[02:58:05] <SWPadnos> just not me
[02:58:11] <cradek> yes, surely somewhere
[02:58:16] <gene> tell me about it. theres a 1500 watt utility thing running, but near zero insulation
[02:58:30] <cradek> gene: those work if you're really close!
[02:58:31] <SWPadnos> aren't yo uin Georgia or something?
[02:58:42] <SWPadnos> battery-powered socks
[02:58:51] <gene> north central wv, 29f outside
[02:59:02] <SWPadnos> oh, WV. that's a bit different
[02:59:09] <cradek> do you have a moon suit (the full body insulated thing construction workers wear?) I love mine for outside work on cold days
[02:59:12] <SWPadnos> weird. about the same temp here
[02:59:28] <SWPadnos> I had moon boots once
[02:59:37] <cradek> I have those too :-)
[02:59:40] <SWPadnos> heh
[02:59:47] <SWPadnos> I can moon walk sometimes
[02:59:47] <gene> they won't let diabetics even buy those things, i checked already. BIG warning signs on them..
[02:59:56] <SWPadnos> the socks?
[03:00:00] <gene> yes
[03:00:09] <cradek> yeah that's a bad idea if you have any lack of feeling
[03:00:18] <SWPadnos> makes sense - you lose a bit of sensation, right? (so you can't tell if they're overheating)
[03:01:19] <gene> probably not, altho i keep a small pad on low at the foot of the bed anyway :)
[03:01:34] <SWPadnos> me too :)
[03:01:42] <gene> whereare you steve
[03:01:47] <SWPadnos> Vermont
[03:01:53] <cradek> heh, I have a waterbed (goes with my moon boots I guess)
[03:01:54] <SWPadnos> http://www.wunderground.com/cgi-bin/findweather/getForecast?query=05452
[03:02:08] <SWPadnos> used to have that - keeps you nice and warm
[03:02:11] <gene> ahh, but you can get colder than we do i think
[03:02:15] <cradek> yeah it's great
[03:02:18] <SWPadnos> most of the time, yes
[03:02:33] <SWPadnos> record colds a week ago (somewhat luckily I was in Winconsin at the time)
[03:04:02] <gene> worst i ever saw it was in rapid city one morning back in the mid-60's, -39F on a thermometer nailed to a jack pine in the front yard.
[03:04:07] <skunkworks> lucky to be in wi - odd
[03:04:11] <SWPadnos> heh
[03:04:22] <SWPadnos> yeah. in this part of the state, we rarely get below -20 or so
[03:04:35] <SWPadnos> I haven't even seen that in a few years
[03:04:51] <SWPadnos> skunkworks, yeah, when you were in Cozumel (unless you're there now), I was in Wisconsin
[03:04:53] <SWPadnos> silly me
[03:05:21] <gene> heck, they call school if its below +20 around here cuz they can't heat them.
[03:06:28] <skunkworks> last week was cozumel
[03:06:47] <SWPadnos> ok. last week was Mishicot for me
[03:06:53] <gene> and you didn't invite me?
[03:06:55] <SWPadnos> I wish it had been Cosumel
[03:06:59] <SWPadnos> ss/z/
[03:07:02] <skunkworks> It was nice. :)
[03:07:14] <SWPadnos> were they still doing construction on the cruise ship pier?
[03:07:26] <skunkworks> yes
[03:07:34] <gene> course i coulda been in iron mountain mi just as easy
[03:07:39] <SWPadnos> figured. it didn't look like a small project
[03:07:48] <SWPadnos> Iron Mountain - that's close to Ray
[03:08:08] <gene> heck it is, which way?
[03:08:25] <skunkworks> We stayed in iron moutain when we took a trip to maine. via canada
[03:08:26] <SWPadnos> Crystal Falls is ~1 hour or something from Iron Mountain
[03:08:42] <SWPadnos> we drove through IM going from Minneapolis to Ray's place
[03:08:50] <gene> less than, about 20 miles i think
[03:09:04] <SWPadnos> probably. couldn't remember for sure so I hedged :)
[03:09:15] <gene> been there a couple of times
[03:11:54] <gene> I wonder if Ray knew Wally, who got cooked at the foundry about 2 years ago this coming summer, got across a 460 volt dc line due to faulty equipment
[03:12:03] <SWPadnos> ouch
[03:12:16] <gene> Wally was fron Crystall Falls
[03:12:33] <SWPadnos> then it seems likely that they would have known of each other
[03:12:57] <SWPadnos> it's not a big town, so I'd assume that people who work with machinery are a very small group there
[03:13:29] <gene> I doubt if he ever felt it, the control pendant for the crane swung and hit him in the head, and it was hot
[03:13:39] <SWPadnos> ouch^2
[03:16:09] <gene> yeah, Wally was 'good people'. his missus went completely off & the kids had to commit her. early alzheimers too from what wally had said. Sad
[03:17:18] <gene> whats in store for 2.2.4?
[03:17:49] <skunkworks> make my slipping on ice an having a piece of 3'X4' cement board fall on my face seem trivial. Yes it just happened tonight.
[03:18:20] <gene> youch!
[03:18:21] <skunkworks> nose is a little bloody.. few bruises..
[03:18:39] <skunkworks> bump on the head.. I am sure other things will ache tomorros
[03:18:42] <skunkworks> tomorrow
[03:18:53] <SWPadnos> ouch
[03:19:09] <SWPadnos> it's true though - hearing about death makes non-death-causeing things seem less severe :)
[03:19:14] <skunkworks> yes
[03:19:16] <gene> i used to call that road rash, you get it from throwing motorcycles away
[03:19:53] <SWPadnos> while using them :)
[03:20:30] <gene> yes of course, last time i had to add a broken rib to the list but i did miss the deer
[03:21:02] <skunkworks> ouch
[03:21:13] <SWPadnos> we keep saying that
[03:21:16] <gene> my gs1000g needed an alternator cover though...
[03:21:23] <SWPadnos> I propose we change the subject ;)
[03:22:24] <gene> somehow thats supposed to make it better i think :) probaby, back to 2.2.4 maybe?
[03:22:39] <SWPadnos> dunno. next subject? :)
[03:23:16] <gene> next time i'm in iron, i'll see if i can find ray
[03:23:35] <SWPadnos> send him an email - you never know if he'll be around :)
[03:24:18] <gene> i think i'm headed that way come warmer weather, some sort of a satellite problem
[03:24:27] <SWPadnos> cool
[03:26:41] <gene> i still haven't figured out how i managed to inherit the maintenance on a tv station 1000 miles away, but it pays well
[03:29:19] <eric_U> don't drink out of the glasses at hotel rooms http://www.divinecaroline.com/article/22250/39039?CMP=DC_0001_TAG
[03:30:59] <gene> plastic cups at the mountain host where i stay. been there so many times now i get christmas cards from Cindy, the manager
[03:35:14] <gene> i just hit the p key and shut the rest down, my feet are about gone & there's a mich ultra in the fridge with my name on it, g-nite guys
[03:51:57] <Ziegler> wow... those #perl guys can be harsh!
[03:53:05] <Ziegler> its like having a room full of crabby fenn's :-P
[03:54:04] <eric_U> gosh, just having a room full of fenns sounds scary enough
[03:54:16] <Ziegler> woah... just cleared the room with that one.
[03:59:08] <Ziegler> alright then... you all have a good one.
[04:09:34] <dave_1> fenn ... u awake??
[04:10:41] <dave_1> no one is admitting anything
[04:11:47] <dave_1> anyone here built apt??
[04:14:11] <dave_1> SWP ??
[04:14:34] <SWPadnos> not me
[04:14:50] <dave_1> that's right ... never admit anything
[04:14:56] <SWPadnos> what? where?
[04:15:06] <dave_1> exactly
[04:15:10] <SWPadnos> "I have no recollection of that event at this time"
[04:15:15] <dave_1> like eh?
[04:15:15] <SWPadnos> "that I can recall"
[04:15:19] <SWPadnos> "in the last 10 years"
[04:15:20] <eric_U> I have too much credibility to even bother denying
[04:15:35] <dave_1> ah... you've been listening to the politicians
[04:15:43] <SWPadnos> (to paraphrase the president, regarding questions about drug use :) )
[04:15:59] <SWPadnos> or alcohol or something
[04:16:12] <dave_1> yep ... or something
[04:16:44] <dave_1> I've not retested ... but I broke a cutter on restart yesterday.
[04:17:10] <dave_1> I normally restart on a G53G0Z0M5 ... before a tool change
[04:17:38] <dave_1> the next line moves to tool change position
[04:18:05] <SWPadnos> what borke the cutter? spindle not turning, movement into the wrokpiece, crashing into a vise ...?
[04:18:06] <dave_1> however on restart it failed to pull the tool and just moved horizontally .. bumer
[04:18:11] <SWPadnos> oh, oops
[04:18:51] <dave_1> yeah ... darned.
[04:19:19] <dave_1> usuallly I'm more careful and do a mdi g53g0z0m5 ... but I got careless
[04:19:45] <SWPadnos> wouldn't tool change position be "above" the work/vise?
[04:20:16] <dave_1> ah yes but I did it in two moves .... z up and then horizontally
[04:20:36] <SWPadnos> hmmm. where is Z0 in all this?
[04:20:57] <dave_1> G53G0Z0M5 ...
[04:21:11] <SWPadnos> right - is that the top excursion of Z on this machine?
[04:21:29] <dave_1> home pos for z ... 5" or so above vise
[04:21:36] <SWPadnos> ok
[04:21:49] <dave_1> The g53 is a non modal G54
[04:22:05] <SWPadnos> right (I remembered that much, this time :) )
[04:22:13] <cradek> no, G53 is 'no offset' (machine coords)
[04:22:29] <SWPadnos> does it also ignore tool offsets and G9x?
[04:22:32] <cradek> yes
[04:22:35] <SWPadnos> ok, cool
[04:22:37] <cradek> machine coords
[04:23:06] <cradek> dave_1: if your program left you in G91, I think your Z0 will not move up
[04:23:11] <dave_1> nice way to say ... stay in G5x and still go someplate temporarily
[04:23:30] <dave_1> true but you do get an error message.
[04:23:41] <cradek> oh? is g53 g91 not allowed?
[04:23:42] <dave_1> I almost never use g91
[04:24:03] <cradek> yeah same here.
[04:24:46] <dave_1> now off to another question ...
[04:24:53] <dave_1> I'm trying to build apt ...
[04:25:21] <dave_1> downloaded the libf2c but don't know where to put it so ./configure will find it
[04:25:45] <cradek> sudo apt-get install libf2c2-dev
[04:26:05] <dave_1> oh ... do it the easy way
[04:26:13] <cradek> always always check for packages first
[04:26:27] <cradek> it's easy to get a mess otherwise
[04:27:02] <dave_1> apt appears to do some interesting things
[04:27:24] <cradek> I agree
[04:27:35] <dave_1> but may still be a pain to use
[04:27:40] <cradek> yeah, I didn't spend enough time to learn to use it
[04:28:15] <cradek> goodnight
[04:28:32] <dave_1> see ya!
[04:28:52] <dave_1> going to go play ..
[06:05:52] <SkinnYPuppY> .
[07:32:12] <micges> good morning all
[12:03:31] <micges> what problem cause net s32 and u32 hal pins ?
[12:08:15] <alex_joni> you can't connect s32 pins to u32 pins
[12:08:22] <alex_joni> unless you use a converter
[12:13:32] <micges> you right my bad
[13:11:23] <skunkworks> You can't have more than 1 index pulse per rev - correct? wouldn't you have issues with the threading starting at 1/2 spindle rotation off?
[13:12:03] <skunkworks> but you could have one ever 2 revs or something.. Seems I remember a discussion about this on the list
[13:14:53] <alex_joni> skunkworks: why would you want that?
[13:15:42] <skunkworks> regards to this post http://www.cnczone.com/forums/showthread.php?p=420828#post420828
[13:16:10] <archivist> * archivist asks the question, does threading have start angle, so two/four start worms can be turned
[13:16:19] <skunkworks> last one. I don't think you would want to gear up the encoder unless the indes was separate and geared the same as the spindle (one per rev then)
[13:19:14] <skunkworks> you can just move Z each time...
[13:32:24] <fenn> archivist: yes
[13:33:39] <archivist> ah goody, I have a couple of worm jobs coming up /me needs a lathe to mod quickly
[13:34:04] <archivist> well 1 worm and two worm wheels
[13:34:37] <fenn> archivist: er, i might be wrong. in any case you can start the thread at pitch/2 away
[13:35:03] <archivist> yes there is that option
[13:35:37] <archivist> I may mill or hob, dunno yet
[13:35:41] <fenn> sometimes there isn't that option, but i bet it's rare
[13:36:07] <archivist> hobbing worm wheels is fun getting the angle correct
[13:36:28] <skunkworks> * skunkworks doesn't want to think that hard
[13:36:46] <archivist> evil differential feed on the hobbing machine
[13:37:30] <archivist> other method "fiddle gear train till looks right"
[13:37:31] <fenn> gearing up an encoder just seems like a dumb idea
[13:38:01] <archivist> yup adds gearing error to system
[13:38:02] <fenn> you can get a 8000 line encoder for like $50
[13:38:15] <fenn> the only excuse is if you can't get a big enough encoder for your spindle
[13:39:03] <Guest572> Morning guys, just wondering what are the advantages of a mesa 5i20 & emc vs lets say flashcut or camsoft? currently running mach3
[13:39:45] <fenn> hm. 8000 counts/rev not lines/rev
[13:40:12] <fenn> Guest572: if you want to go with the herd, then mach3 is great
[13:40:34] <Guest572> using mach 3 now slaved gantry but lost steps cause chatter sometimes
[13:40:44] <Guest572> also the 3d is really jerky
[13:41:40] <Guest572> from what i understand the 5i20 is a motion controller, so emc offloads the motors to the card right?
[13:41:44] <fenn> no
[13:42:02] <fenn> 5i20 is an FPGA which means it can do simple electronic tasks very quickly
[13:42:17] <fenn> so for instance counting encoders or doing PWM
[13:42:43] <Guest572> ok so tere is no advantage from a 5i20 / parall port as far as steps
[13:42:43] <fenn> the PID loop is done in emc (technically it's in HAL)
[13:42:54] <Guest572> i'm running a stepper system
[13:43:14] <fenn> parallel port will get you maximum 50kHz and that would be herky-jerky due to aliasing
[13:43:56] <fenn> in general, if you want to go higher than say 10,000 steps/sec you should use hardware step generation
[13:44:39] <fenn> * fenn looks at flashcut and camsoft
[13:45:06] <fenn> Guest572: do you know the difference between a step servo and a true servo?
[13:45:19] <Guest572> does the 5i20 do step generation?
[13:45:33] <Guest572> i'm using steppers,
[13:45:47] <Guest572> servo's are dc/ac motors using an encoder for position feedback
[13:46:06] <Guest572> steppers are perm magnet motors by turning on/off coils you can controll the rpm
[13:46:36] <fenn> step-servos are when you control a servo motor using step/dir signalling
[13:46:41] <Guest572> k
[13:46:51] <fenn> true servo is when you control the current (torque) to the motor
[13:47:18] <fenn> so when something says "supports steppers and servo" and then they show their step/dir interface, i call bullshit
[13:47:27] <Guest572> ahhhhhhh
[13:47:40] <Guest572> supports servo's in a stepping fashion
[13:47:43] <fenn> right
[13:47:50] <fenn> the control doesnt know what's on the other end
[13:48:08] <Guest572> my main thing would be external stepgen to offload the cpu and make sure all the steps get processed
[13:48:31] <fenn> if you dont use step/dir signalling then the cpu has much less to worry about
[13:48:50] <fenn> you can do essentially infinite speed/resolution (as far as CNC machines go)
[13:48:58] <archivist> your step loss may not be cpu, could be running too fast or friction in the machine etc
[13:49:03] <Guest572> but as i am allready setup using steppers need to go with that
[13:49:56] <fenn> also there are two ways to do 'external step generation' - a PLL and something that essentially acts like a true servo interface
[13:50:55] <fenn> anyway, it sounds like you need to figure out what is causing your lost steps
[13:50:59] <Guest572> i think i came accross a board that makes the pc see the steppers as sevo's, had an onboard counter
[13:51:32] <fenn> once you know what's going on, you can decide where to throw money
[13:51:36] <Guest572> lol
[13:51:39] <Guest572> yeah
[13:51:53] <archivist> dont forget to figure in cutting load to your max speed
[13:52:15] <fenn> yep learn a bit about stepper motor physics
[13:52:36] <Guest572> perhaps what i am going to do is bridge my gantry motors instead of slaving and see what happens, i have a very wide gantry
[13:52:41] <archivist> torque drops off with speed rapidly
[13:52:52] <Guest572> cutting speed is only 167ipm
[13:53:30] <fenn> Guest572: simple enough to detect if the motors are slaved properly, just put a little flag on each leadscrew. if the flags are pointing in the same direction it should be fine
[13:53:38] <archivist> what step rate is that, whats the spec of the motors at that rate
[13:54:07] <Guest572> rach and pinion :)
[13:54:25] <Guest572> stepp rate @6200
[13:54:30] <Guest572> steps/inch
[13:55:03] <fenn> that's a pretty high step rate (17kHz for the peanut gallery)
[13:55:27] <Guest572> yeah cause of R&P and gearing
[13:55:56] <archivist> likely low torqu at that speed , try slower
[13:57:10] <archivist> a lot of motors max at about 3khz
[13:59:02] <fenn> it gets confusing with microstepping, so you should really talk about rpm
[13:59:08] <fenn> like, torque falls off at 1000-1500 rpm
[13:59:25] <Guest572> running 1290 oz/in Stepper Motor Model # RS34-1290 from homeshopcnc
[14:00:37] <fenn> no specs :(
[14:00:43] <Guest572> i know
[14:01:05] <Guest572> broke a 3/8 endmill on a clamp though so torque is pretty high
[14:01:06] <fenn> "welcome to homeshopcnc.com, we drop ship to your door without ever seeing the product"
[14:01:14] <Guest572> lol
[14:01:22] <Guest572> haha
[14:01:43] <fenn> oh wait maybe they do ship their own inventory
[14:03:54] <fenn> there are specs on this page but i dont know if its possible to convert that to a torque curve http://www.homeshopcnc.com/page5.html
[14:06:16] <Guest572> thanks for the info fenn, gotta run to work
[14:19:09] <fenn> skunkworks: since i know you love remodeling pictures: http://fennetic.net/pub/camera/DCP_0797.JPG ... to 799
[14:19:31] <fenn> the walls ceiling and floor used to be the color of that purple door
[14:19:56] <fenn> and half a dozen holes
[14:20:47] <skunkworks> Nice job. I hate plastering.
[14:22:07] <fenn> its much easier with a power sander
[14:22:12] <skunkworks> heh :)
[14:23:02] <skunkworks> fen with a beard.. I don't know if I could get used to that.
[14:23:18] <fenn> me have a beard? where?
[14:24:25] <fenn> i prefer to cultivate a fine layer of stubble. if you call that a beard, well..
[14:24:34] <archivist> hmm my beard is 35+years old
[14:24:53] <skunkworks> This isn't you? http://fennetic.net/pub/camera/?Qwd=.&Qif=DCP_0131.JPG&Qiv=thumbs&Qis=M
[14:25:04] <skunkworks> It has been a while since I have seen you..
[14:25:17] <fenn> eh ok that's a beard, probably before you met me
[14:25:29] <skunkworks> ah
[14:25:48] <archivist> heh bum fluff get a beard
[14:26:35] <fenn> nevarr
[14:27:48] <skunkworks> http://fennetic.net/pub/camera/?Qwd=.&Qif=DCP_0494.JPG&Qiv=thumbs&Qis=M
[14:27:54] <skunkworks> camping and electronics?
[14:28:36] <skunkworks> those don't mix very well ;)
[14:28:42] <fenn> i decided that being in the middle of untouched forest would be a great place to do gravity wave research
[14:28:58] <fenn> hundreds of miles from any electrical lines
[14:29:27] <fenn> the results were.. inconclusive
[14:30:07] <skunkworks> don't you need mirrors and lasers? ;)
[14:30:59] <skunkworks> cd burner writer laser. http://www.cnczone.com/forums/showthread.php?t=53398
[14:33:02] <fenn> were you here when the guy was talking about melting solder with a diode laser?
[14:33:24] <fenn> he was making fpga cards for servers or something
[14:33:47] <skunkworks> no - neat
[14:35:17] <fenn> it had a heatsink at least (the diode)
[15:29:38] <alex_joni> bbl
[15:50:32] <skunkworks> fenn: that computer does not sound like a good real time machine..
[15:50:49] <skunkworks> 1ms when moving windows around? come on now :)
[16:00:11] <skunkworks> couldn't you effectivly take the backlash out of a hexipod by loading the pairs against each other?
[16:26:57] <fenn> skunkworks: that's why i said "with x disabled..."
[16:26:57] <fenn> and no, it doesn't work. you get rotation in the C axis
[16:26:57] <fenn> but that's a good thing because it means the mechanism can't bind
[16:27:49] <skunkworks> fenn: thanks.
[16:27:51] <SWPadnos> fenn, the 44-pin IDE connector is for a standard laptop drive
[16:28:01] <SWPadnos> (in case you hadn't found that out already)
[16:28:12] <SWPadnos> the extra pins provide power
[16:28:16] <fenn> yah i know, but the cable is hard to find
[16:28:24] <SWPadnos> really?
[16:28:37] <skunkworks> I think I have one I could send you..
[16:28:37] <fenn> or maybe i looked in all the wrong places
[16:28:51] <SWPadnos> there are adapters as well - pretty easy to find when I last looked a couple of years ago
[16:28:54] <fenn> i built one from scratch, and now i've got parts to make more if i need to
[16:28:57] <SWPadnos> cables I can imagine being hard
[16:29:07] <skunkworks> We had a embedded computer that took a dump.
[16:29:53] <skunkworks> I want to ask this guy why not emc http://www.foxkid.net/cmm/platform/project-notebook.html
[16:30:08] <fenn> he probably didnt know about it
[16:31:34] <fenn> Your search - site:foxkid.net emc - did not match any documents.
[16:32:00] <SWPadnos> those pages were done in 2000. EMC wasn't anywhere near as well-known at the time
[16:32:57] <skunkworks> I suppose
[16:33:39] <fenn> back around 2000 google wasn't as well known either
[16:34:17] <fenn> there was stuff like altavista, webcrawler
[16:35:53] <SWPadnos> metacrawler
[16:36:13] <bill20r3> hotbot, now with more annoying colors.
[16:37:17] <cradek> machining an end mill shank with a ceramic tool on a sherline: http://sherline.com/images/CutWithCeramic.mpg
[16:37:22] <skunkworks> I remember using altavista. Didn't they have free internet for a while also?
[16:41:59] <skunkworks> I wonder how ceramic tools like interupted cuts... Would be a nice way to machine ball screw ends
[16:44:52] <fenn> just grind it off by hand first
[16:46:23] <fenn> sure, now there are hundreds of 44 pin ide cables on ebay
[16:46:37] <SWPadnos> 44 -> 40, or 44-pin?
[16:46:50] <fenn> 44 to 44
[16:47:09] <fenn> there are lots of adapters
[16:48:11] <SWPadnos> ah. I thought that was what you had looked for - an adapter to use a full-size drive with the 44-pin motherboard connector
[17:37:52] <skunkworks> fenn: how did this work out? that is one heck of a casting. http://fennetic.net/pub/camera/qdig-files/converted-images/med_DCP_0265.JPG
[18:33:39] <skunkworks> pete is answering mesa questions on cnczone. cool
[18:37:32] <skunkworks> http://www.cnczone.com/forums/showthread.php?t=53966
[18:41:45] <archivist> that q is much like a visitor we had a couple of hours ago
[18:47:25] <skunkworks> yes
[18:53:14] <fenn> skunkworks: you can see in the pic that it didn't fill all the way, i dont remember what went wrong exactly. anyway it worked the next time
[18:54:14] <skunkworks> what was it for?
[18:54:28] <fenn> tailstock for my gingery lathe
[18:55:23] <fenn> i wanted a lever-actuated tailstock for drilling, and also a leadscrew actuated tailstock for centering and accurate drilling, so i came up with a linkage that allowed that
[18:55:56] <fenn> and the t-slot top is just because i was fed up with not having suitable surfaces to bolt stuff to
[18:57:24] <archivist> cnc tailstock next?
[19:07:25] <skunkworks> Neat
[19:07:48] <skunkworks> fenn: How is the cnc'ing of it coming?
[19:08:09] <fenn> delayed by yak shaving
[19:09:29] <archivist> shaving ... nevar!
[19:11:20] <skunkworks> fenn: is the commercial lathe yours also?
[19:11:46] <fenn> i bought the atlas 10" from roland
[19:12:28] <skunkworks> Nice
[19:12:55] <skunkworks> did it come with the milling attachement?
[19:13:18] <fenn> yes it came with every attachment i know of
[19:13:42] <skunkworks> very nice
[19:14:14] <fenn> oh, no toolpost grinding attachment
[19:15:23] <skunkworks> darn ;) I hate grinding on a nice lathe.
[19:15:38] <skunkworks> no matter how well you protect things
[19:15:56] <fenn> yeah i will save that for the gingery which is expendable :P
[19:16:14] <fenn> not like i find myself needing to grind things
[19:16:22] <skunkworks> heh
[19:18:18] <skunkworks> so... When is your mill purchase happening?
[19:18:34] <fenn> nevar!!!
[19:18:48] <skunkworks> I give it a year ;)
[19:18:53] <fenn> hexapod or bust
[19:19:01] <skunkworks> oh - ok. That will be fine.
[19:19:16] <fenn> i'll put a Z slide on the gingery, dont worry
[19:20:29] <fenn> this week i finally put a chip tray under the atlas
[19:21:12] <skunkworks> can't rush into these things..
[19:21:53] <archivist> heh dont buy a mill, make it
[19:23:16] <fenn> it's really not that hard if you know what you're doing
[19:23:47] <archivist> my home made is cutting a pinion right now
[19:26:17] <fenn> heh cncmarinesupply is "chris and carol"
[19:26:44] <archivist> here is just two of us
[19:28:01] <archivist> gear cut /me escapes to play
[19:28:42] <fenn> enjoi
[19:34:52] <skunkworks> * skunkworks really would like a hexapod...
[19:35:12] <skunkworks> You could make it so it would dissasemble into a suitcase..
[19:35:26] <skunkworks> all pipes and connectors
[19:36:39] <fenn> well almost
[19:37:12] <skunkworks> sure - rain on my parade
[19:37:14] <skunkworks> ;)
[19:37:31] <fenn> one thing that's annoying me is how to make bulletproof windows that dont take up too much space
[19:38:05] <fenn> so far the best solution is a nylon webbing with plastic
[19:38:19] <skunkworks> around the pod?
[19:38:34] <fenn> yeah flexible triangular panels
[19:38:57] <skunkworks> neat
[19:39:04] <fenn> they could split in half so you could rearrange them as a square instead of triangles
[19:39:21] <fenn> or you could just fold them i guess
[19:40:51] <fenn> the longest dimension would be the same as the frame member
[19:41:14] <fenn> only problem is, what do you do with the suitcase? :)
[19:41:21] <skunkworks> it is the table..
[19:43:01] <skunkworks> t-slotted suitcase ;)
[19:43:46] <skunkworks> a 6 sided suitcase would be cool
[19:43:46] <fenn> another possibility is to ship it in a cylinder or hexagonal prism
[19:44:08] <fenn> then you just roll stuff up instead of trying to make a neat tidy square out of it
[19:44:19] <skunkworks> yes
[19:44:37] <fenn> i think a hexagonal table would work well, and the moving platform too
[19:46:03] <fenn> * fenn pictures a folded up hexapod wrapped in heavy vinyl windows and lashed with bungee cords
[19:46:28] <fenn> maybe a little overkill on the portability aspect
[19:47:19] <fenn> but if it used an additive method like FDM then you wouldn't need big blocky raw materials
[19:48:38] <alex_joni> * alex_joni just had another cookie
[19:48:39] <skunkworks_> sorry - ie crashed
[19:50:42] <alex_joni> why would you be sorry?
[19:50:52] <fenn> because he uses ie?
[19:51:04] <alex_joni> he should be glad, it still works after a crash
[19:51:26] <alex_joni> not that uncommon for ie to stop working at all :D
[19:52:24] <fenn> yeah that happened, i installed firefox, now six months later the computer's totally hosed
[19:52:32] <fenn> not my problem
[19:53:09] <fenn> i really dont understand how people can actually use windows
[19:54:12] <alex_joni> bad habits die hard
[19:55:42] <micges> logger_emc: bookmark
[19:55:42] <micges> Just this once .. here's the log: http://www.linuxcnc.org/irc/irc.freenode.net:6667/emc/2008-03-06.txt
[19:56:25] <skunkworks_> more of an addiction...
[19:58:01] <jymm> meta2-18~
[20:44:20] <SWPadnos> I have two of them at the moment (for this nick)
[20:44:26] <SWPadnos> err - oops
[20:46:10] <SWPadnos> sure
[20:46:13] <SWPadnos> gah
[21:03:01] <skunkworks_> ummm - yah.
[21:17:32] <SkinnYPuppY> heh regedit yum