#emc-devel | Logs for 2007-08-10

[01:50:11] <jmkasunich_> jmkasunich_ is now known as jmkasunich
[12:49:31] <Guest776> Guest776 is now known as skunkworks_
[14:12:29] <jepler> jmkasunich__: thanks for answering kirk wallace's question about FPR. All I could remember is that I wrote it to use position at first, and then I got bullied into changing it to velocity :-P
[14:19:44] <cradek> Hi Steve S! Have you done an emc conversion of a BP R2E3?
[14:24:02] <steves_logging> steves_logging is now known as steve_stallings
[14:24:34] <cradek> I see you there lurking! :-)
[14:24:39] <steve_stallings> Hi Chris. No conversion, but have worked on original R2E3 electronics.
[14:24:52] <cradek> terrific
[14:25:02] <steve_stallings> Steve hides....
[14:25:24] <cradek> what can you tell me about the encoders and amps?
[14:25:51] <cradek> I'm thinking about buying one that's nearby, but I wonder if there are any big traps awaiting
[14:27:27] <cradek> I wish I could find old BP service manuals online, like HP has - that would be really nice
[14:28:00] <steve_stallings> The original amps are PWM at a low enough frequency to be quite audiable and mildly annoying, but work well. The do have velocity feedback from tachs. Encoders are moderate resolution (i.e. not 1000 line, more like 200 line) conventional quadrature.
[14:28:47] <steve_stallings> I have manuals, but do not know of any electronic versions. Schematics are chip level and useful, if somewhat cluttered and hard to read.
[14:28:50] <cradek> ok, 200 line/.2 inch = 4000 count/inch, good enough for me
[14:29:11] <skunkworks_> direct drive?
[14:29:31] <cradek> oh good question - they surely have belts, I don't know the gearing
[14:29:34] <steve_stallings> Encoders are fine for systems with tach feedback, marginal without it.
[14:30:19] <cradek> so the tach goes right to the amps? do you know if the amps are normal +-10 analog, or does the control have to generate that pwm?
[14:30:22] <steve_stallings> I think belts were 2:1 but not sure, memory is weak here.
[14:30:37] <jepler> cradek: don't forget that 200 line is 800 count
[14:30:49] <cradek> jepler: right I had that in there
[14:30:55] <jepler> cradek: OK nevermind
[14:30:55] <steve_stallings> Amps are normal +/- 10 VDC differential inputs.
[14:31:15] <cradek> so with 2:1 that's 8000/inch, seems fine
[14:31:29] <cradek> steve_stallings: this is very good news
[14:31:46] <steve_stallings> Tachs feed amp directly. Amp has analog current loop, analog velocity loop, and the usual gain an offset adjustments.
[14:33:02] <steve_stallings> Cradek - did you get an R2E3 already, or just hot on the trail?
[14:33:24] <cradek> a guy 70 miles from here has two for sale, I've talked to him but not visited yet
[14:34:32] <cradek> steve_stallings: how does the original control work? I think he's drip feeding his over serial but I'm not sure
[14:34:59] <cradek> did they take tape normally? (It doesn't look like you can really program it at the control)
[14:35:39] <steve_stallings> In good condition they are impressive for their age. I helped my friend Leroy get his running and it will CNC a round hole 2" dia. accurate enough to press bearings into the hole.
[14:36:27] <cradek> nice.
[14:37:20] <steve_stallings> Original control is a trip! Parsing was done by a Zilog Z8000, as was the operator interface. Motion control was done by a MC68000 (64 pin DIP no less), and for good measure there is an 8051 machine monitor for the "oh shit" stuff.
[14:37:49] <cradek> haha, three guys designed it, each with their favorite processor
[14:38:34] <steve_stallings> Control supports MDI with some useful canned cycle support. Display is weak point. Single line, cryptic error messages.
[14:39:08] <steve_stallings> Internal memory is somewhat limited, but has on board single line editor and full support for RS232 download and editing.
[14:40:04] <steve_stallings> Design is even more interesting.... various ancient stuff like DTL thrown in at a few places for good measure.
[14:40:20] <cradek> wow.
[14:40:48] <steve_stallings> The MC68000 has an extra RS232 port with a crude debug monitor.
[14:41:33] <cradek> well I sure found the right guy to ask about this.
[14:41:56] <cradek> one problem is I'll have to take the head off to get it in my garage. Is that shroud complex, or is it just a bit of control panel?
[14:42:07] <steve_stallings> I got luck. The manuals were available and there was, back then, still someone at Bridgeport to talk with.
[14:43:31] <steve_stallings> The plastic shroud come off easily. Getting the head of is a fair size job. If all you need is a couple of inches, you may be in luck.
[14:43:56] <cradek> unfortunately I need about 4" of height
[14:44:43] <cradek> I've got an 8'+ ceiling, 7'0 garage door, the series 1 seems to measure 7'3
[14:44:46] <steve_stallings> Well... I have one also, never hooked up, but I can run out the shed and have a look. Back in a few...
[14:45:01] <cradek> ooh thanks
[14:55:51] <steve_stallings> OK, the top half of the pulley housing is 5.5" tall. It comes off easily, but then you will need to get pulleys and other stuff off to gain the desired result.
[14:56:44] <steve_stallings> You can also take the drive system off the quill block and get about 10". This is also conceptually simple, but stuff is heavy.
[14:57:13] <cradek> heavy is ok - I'll be renting the necessary equipment
[14:57:16] <steve_stallings> I do not recommend detaching the quill block (head) from the ram/column.
[14:57:27] <cradek> ok
[14:58:18] <cradek> I've also been told the opposite - don't take the pulley housing apart because parts will fly everywhere, take the whole head off instead
[14:58:47] <cradek> (and, I know nothing firsthand about doing either one)
[14:59:11] <cradek> looking for photos of the thing so I can see what you mean...
[14:59:16] <steve_stallings> On a V-ram machine, I would agree, but the R2E3 is a rigid ram and the head block is semi-permanenly aligned to the column.
[14:59:46] <steve_stallings> lost a t somewhere in there...
[15:03:22] <cradek> ok in this photo I see the same 4 bolts that hold the head on as on the older series 1 cnc - but I should not detach it there?
[15:03:59] <cradek> (can't see much with that shroud)
[15:04:29] <cradek> http://timeguy.com/cradek-files/emc/IMG_0947_1.JPG
[15:04:30] <cradek> http://timeguy.com/cradek-files/emc/IMG_0948_1.JPG
[15:04:33] <cradek> http://timeguy.com/cradek-files/emc/IMG_0949_1.JPG
[15:07:54] <steve_stallings> OK, in your last photo, everything above the shroud plus the main drive motor hanging down into the shroud, will come off in one piece.
[15:09:10] <steve_stallings> This will leave the Z axis motor and or the quill spline drive as the high points.
[15:11:57] <skunkworks_> cradek: is that the one your looking at?
[15:12:02] <cradek> skunkworks_: yes
[15:12:09] <skunkworks_> nice
[15:12:21] <cradek> steve_stallings: I'm trying to find another photo without the shroud so I can try to see what you mean
[15:13:12] <steve_stallings> While I am thinking about it, the most annoying problem when servicing these machines is having the Z axis retract past intended point. Lots of drive torque and it will bind up pretty hard. Requires brass drive punch applied to ball nut pulley to release in some cases.
[15:13:11] <skunkworks_> does the quill move on this? or is it only the knee? both?
[15:13:17] <cradek> both
[15:13:40] <cradek> quill is Z, knee is manual
[15:13:49] <steve_stallings> Knee is manual and should be locked during CNC cutting.
[15:14:05] <skunkworks_> ah - ok - I thought the servoI was seeing was for the knee.
[15:14:22] <skunkworks_> I see the crank now
[15:14:24] <cradek> skunkworks_: no the X servo is stationary and turns the nut
[15:14:34] <steve_stallings> X axis servo is mounted on knee and spins X axis nut.
[15:14:51] <cradek> which is nice because it doesn't stick out - I have very limited space
[15:14:56] <skunkworks_> ah - I saw that on one of the BP machines/heads at the cnc workshop
[15:15:38] <cradek> steve_stallings: http://www.nw-technologies.com/images/bridgeportCNC1.jpg
[15:15:43] <cradek> this is the same head I think?
[15:17:18] <steve_stallings> Mechanically very similar. The part with the speed dial and everything above and behind it comes off. The square looking block under it hides the ballscrew and would not come off.
[15:17:59] <cradek> nice, that would give me plenty of clearance to move it
[15:18:46] <cradek> what is there to deal with at that top pulley? does it just lift off a spline or something?
[15:19:10] <steve_stallings> Getting 200 lbs. remounted with little overhead clearance will be the challenge.
[15:19:37] <skunkworks_> is you garage finished - or do you have 2 foot on center trusses?
[15:19:44] <cradek> there's a hole in the ceiling for attic access, and I can hang a block&tackle from the roof there
[15:19:49] <skunkworks_> ah
[15:19:59] <cradek> only 200 lbs will be very easy
[15:20:23] <steve_stallings> Tell me that AFTER you have done it!
[15:20:40] <skunkworks_> ;)
[15:23:28] <cradek> haha
[15:23:52] <cradek> well I was planning to have to lift the whole head - now it sounds easy compared to that
[15:24:15] <cradek> I was going to get those screw jacks that hold up houses for foundation work
[15:24:20] <steve_stallings> all things are relative..
[15:24:24] <cradek> right
[15:24:41] <steve_stallings> Let me know if/when you get it and I will make you copies of relevant documentation.
[15:24:42] <cradek> then attach a 4x4 to the ceiling and hold it up with the jacks
[15:24:56] <cradek> ceiling would not support weight but would keep it from tipping over
[15:25:49] <cradek> steve_stallings: thanks a million, I'll definitely do that if I get it
[15:27:24] <steve_stallings> Also, try hard to get toolholders with it. They can be a bit dear even on eBay.
[15:27:47] <cradek> ok I'll keep that in mind
[15:28:25] <cradek> if one of these is in good shape and running today, about what do you think it's worth?
[15:30:56] <steve_stallings> Maybe $3K to $4K if reliable and has tooling. I paid $6K for mine, but that was before Bridgeport went belly up. If known dead but good mechanicals $1K to $2K.
[15:32:09] <cradek> thanks again steve, this is very helpful
[15:32:22] <skunkworks_> http://cgi.ebay.com/BRIDGEPORT-SERIES-1-R2E3-3-AXIS-CNC-MILLING-MACHINE_W0QQitemZ220133836766QQihZ012QQcategoryZ12584QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
[15:32:49] <steve_stallings> Got a running Kitamura #0 with toolchanger in running condition for $6K recently. Smaller, even less support available, but high quality machine.
[15:33:04] <cradek> skunkworks_: yeah, people seem to try $2500, and they don't sell
[15:33:08] <skunkworks_> so less than that :)
[15:33:31] <cradek> skunkworks_: "LOOKS IN NICE CONDITION" <- not working
[15:34:27] <skunkworks_> http://cgi.ebay.com/BRIDGEPORT-MILLING-MACHINE-SERIES-1-CNC-R2E3_W0QQitemZ320140714778QQihZ011QQcategoryZ12584QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
[15:34:28] <steve_stallings> but relisted and now bid up to $2325, go figure..
[15:34:32] <skunkworks_> 2500 again
[15:35:35] <steve_stallings> oh, I know this seller, basically honest, but he really does not know anything about the stuff he sells
[15:41:50] <skunkworks_> cradek: I see a 7I33 in your future.
[17:05:24] <steve_stallings> steve_stallings is now known as steves_logging
[17:13:02] <skunkworks_> NOW thru August 31st!!! All customers receive the 1,000 piece pricing!
[17:13:12] <skunkworks_> oops
[19:59:08] <cradek> if someone wants to fix/change the rpm/rps thing, he should do it before 2.2.0
[20:01:00] <skunkworks_> he/she? oh. we need more women programmers. I could work on that. ;)
[20:01:51] <skunkworks_> actually - I really can't. I don't know any.
[20:03:45] <cradek> at NAMES in 2004? I remember there were some bored wives there. Only a bit later, there was a call on the intercom "attention wives! we're getting together some vans to go to the mall. meet us in front."
[20:04:07] <cradek> then, no wives around anymore.
[20:06:09] <jepler> that's terrible
[20:06:28] <cradek> well, it's a true story
[20:06:38] <cradek> it was a bit surreal.
[20:07:15] <skunkworks_> My wife would do the same.. we she wouldn't come in the first place :)
[20:07:28] <skunkworks_> well
[20:07:29] <jepler> I know some women who would be equally in hell if they were at a mall or at CNC Workshop / Fest
[20:08:03] <jepler> I think that ultimately they'd skip the mall and suffer at the Workshop, in fact
[20:08:02] <cradek> sure but do you know any who would enjoy being at cnc workshop / fest?
[20:08:14] <cradek> that's the real question here.
[20:08:21] <skunkworks_> I know of no one.
[20:09:06] <skunkworks_> well - actually I have a cousin that make jewelery - she always likes to come to the shop to see what we are working on.
[20:09:12] <jepler> is doing this worse than the diseases?
[20:09:12] <jepler> hal_float_t *spindle_speed_out; /* spindle speed output (RPM) */
[20:09:13] <jepler> hal_float_t *spindle_speed_out_rps; /* spindle speed output (RPS) */
[20:09:13] <jepler> hal_float_t *spindle_speed_in; /* spindle speed measured (RPS) */
[20:09:20] <skunkworks_> Nice
[20:09:35] <cradek> oh man, I dunno jeff
[20:10:18] <cradek> but I equally hate the idea of *60 scale blocks being needed all over the place
[20:10:57] <jepler> you'll end up with them anyway, when you want a spindle speed display
[20:11:09] <jepler> since any change should be to use RPS exclusively in motion
[20:11:21] <cradek> yeah
[20:11:28] <cradek> maybe that is the best idea
[20:11:57] <cradek> you can loop one back for vel input, and hook one to your display if you want
[20:12:50] <jepler> should I name spindle-speed-in to spindle-speed-in-rps ?
[20:15:05] <cradek> whatever you decide, it's not my fault
[20:16:57] <jepler> hah
[20:18:01] <jepler> 32770 float IN 1.666666 motion.spindle-speed-in <== spindle-rps-filtered
[20:18:03] <jepler> 32770 float OUT 100 motion.spindle-speed-out ==> spindle-speed-cmd
[20:18:06] <jepler> 32770 float OUT 6000 motion.spindle-speed-out-rps
[20:18:10] <jepler> hm I don't think I got it right
[20:19:07] <cradek> I can find my left hand in only two tries
[20:52:46] <alex_joni> hi guys
[20:56:46] <skunkworks_> back?
[20:56:56] <alex_joni> yeah :)
[20:57:21] <alex_joni> I played with a nice 6kV laser
[20:57:30] <skunkworks_> kw
[20:57:30] <skunkworks_> ?
[20:57:35] <alex_joni> err. yeah
[20:57:37] <alex_joni> kW
[20:57:38] <skunkworks_> nice
[20:57:50] <alex_joni> it was surprisingly .. small
[20:57:53] <skunkworks_> * skunkworks_ has only played with a 1kW
[20:58:18] <alex_joni> this was a fiber-laser, nto CO2 nor YAG
[20:58:28] <skunkworks_> what was it?
[20:59:06] <alex_joni> fiber-laser
[20:59:10] <alex_joni> that's the name
[20:59:15] <skunkworks_> interesting
[20:59:20] <alex_joni> it generates the laser beam inside the fiber
[20:59:43] <alex_joni> and they don't have a real limit for laser power
[20:59:55] <alex_joni> I think they have 30+ kW right now
[21:00:24] <skunkworks_> yikes
[21:00:35] <alex_joni> http://en.wikipedia.org/wiki/Fiber_laser
[21:01:01] <alex_joni> the nice thing is that they have modules of ~300W or so
[21:01:12] <alex_joni> and you simply stack a bunch of those modules together to get a bigger laser
[21:01:30] <alex_joni> they all shoot inside a smaller fiber, which gets bundled into the big one
[21:01:40] <alex_joni> big beeing around .4mm diameter
[21:02:04] <skunkworks_> that is really cool
[21:02:53] <alex_joni> the one I worked with was an Ytterbium Fiber Laser from IPG
[21:03:12] <skunkworks_> where you cutting or welding?
[21:03:16] <skunkworks_> or both
[21:03:21] <alex_joni> the really cool thing is that they have about 30% efficiency
[21:03:27] <skunkworks_> nice
[21:03:27] <alex_joni> I did welding
[21:03:32] <alex_joni> eeek
[21:03:43] <alex_joni> "Output power ... to 50kW"
[21:03:59] <alex_joni> floor space .. < 1m^2
[21:04:03] <skunkworks_> you could take down satallites.. ;)
[21:04:14] <alex_joni> http://www.ipgphotonics.com/apps_materials_multi.htm
[21:05:24] <alex_joni> here it is: http://www.ipgphotonics.com/apps_mat_multi_YLR.htm
[21:05:53] <alex_joni> skunkworks_: I got some pictures with the door open
[21:06:01] <alex_joni> bug me in a couple of days to put them online
[21:06:06] <skunkworks_> diode life? are they using the diodes at the light source?
[21:06:07] <skunkworks_> ok
[21:06:15] <skunkworks_> for excitation?
[21:06:45] <alex_joni> diodes for the light source
[21:07:01] <alex_joni> pumping into the fiber
[21:07:08] <skunkworks_> very neat
[21:07:31] <alex_joni> 86x81x150 cm for 5kW is soo cool
[21:07:50] <alex_joni> think 2 washing machines stacked on top of each other
[21:08:02] <alex_joni> 500kg
[21:08:45] <skunkworks_> yes - our 1000W laser is a box 2mX1mX3m about
[21:09:04] <alex_joni> the 10kW is just as big, just a bit heavier
[21:09:14] <skunkworks_> lots of glass :)
[21:09:26] <alex_joni> well.. not really ;)
[21:09:29] <skunkworks_> ;)
[21:09:57] <alex_joni> hundreds of meters of 100 micrometer glass
[21:10:53] <alex_joni> anyways.. the point of the thing was to put those 5kW inside a MAG welding pool
[21:12:18] <skunkworks_> I can't remember - did you see this? http://www.youtube.com/watch?v=dKz81fY1OjY
[21:12:35] <alex_joni> oh cool.. no I didn't
[21:13:17] <alex_joni> I thought that file isn't for actual machining :P
[21:13:54] <skunkworks_> jepler pointed that out.. I never read the comment :)
[21:15:09] <alex_joni> I only said that because it's the most used file for testing a new machine :D
[21:15:17] <skunkworks_> it zips around pretty good for only using 1/2 the coils
[21:15:24] <alex_joni> cool
[21:15:26] <alex_joni> 3 axes?
[21:15:27] <skunkworks_> yes
[21:15:32] <alex_joni> I only saw 2 drives
[21:15:53] <alex_joni> or is the smaller one another drive?
[21:16:05] <skunkworks_> 2 big parker s6 drives and one small oem650. grey thing on the left.
[21:16:10] <skunkworks_> right I mean
[21:16:37] <skunkworks_> I grabbed 2 s6 drives as they have internal power - just older.
[21:16:45] <alex_joni> they look professional :P
[21:16:57] <skunkworks_> heh - don't look at the wireing
[21:17:00] <skunkworks_> wiring
[21:18:14] <skunkworks_> cradek says there are quite a few emc2 videos on youtube now. He didn't find any bdi though :)
[21:20:23] <alex_joni> bdi users are too cool for youtube
[21:20:24] <alex_joni> ROFL
[21:29:45] <skunkworks_> hmm breaker blew
[21:30:01] <skunkworks_> thank goodness I bought a new ups
[21:30:46] <alex_joni> yup
[21:30:53] <alex_joni> installed NUT already?
[21:31:41] <skunkworks_> NUT?
[21:33:49] <skunkworks_> ? http://www.networkupstools.org/
[21:34:13] <skunkworks_> bbl
[21:46:12] <alex_joni> * alex_joni heads to bed
[21:46:14] <alex_joni> good night all