#emc-devel | Logs for 2006-09-29

[00:42:19] <jmkasunich> hi guys
[01:11:45] <cradek> hey
[01:12:38] <cradek> * cradek is playing mr. fixit tonight
[01:13:31] <cradek> don't you hate those crappy old appliances that need to be repaired every 25 years?
[01:17:44] <cradek> some nice changes in emc - kruft removal and improvements in ini clarity
[01:19:09] <jmkasunich> yeah, the commit list has been busy
[01:19:15] <jmkasunich> I'm doing fixit too
[01:19:29] <jmkasunich> digging into the lathe to acces the motor (with the blown run cap)
[01:25:31] <jmkasunich> I hate wires
[01:34:11] <skunkworks> I hate the smell of the hardener part of epoxy.
[01:36:18] <skunkworks> I bought some 500v 45a mosfets - dont tell jmk though
[01:36:25] <jmkasunich> ;-)
[01:43:28] <cradek> going to use pwm for your huge machine?
[01:44:02] <jmkasunich> how huge?
[01:45:52] <jmkasunich> pretty fragmented conversations tonight
[01:46:19] <cradek> I don't know what he's planning, I was hoping he'd elaborate4
[01:46:29] <jmkasunich> what are you fixing?
[01:46:55] <cradek> tonight I fixed the old washing machine at the rental, and my car's washer pump
[01:47:18] <jmkasunich> 25 years on a washer is pretty good
[01:47:25] <jmkasunich> don't make em like that anymore
[01:47:28] <cradek> err dishwasher
[01:47:38] <jmkasunich> same difference
[01:48:01] <cradek> I just cleaned the contacts on all the switches - its timer wasn't running
[01:48:12] <jmkasunich> good for another 5 years now
[01:48:17] <cradek> and sprayed them with deoxit
[01:48:32] <cradek> yeah, maybe 10 or more, it doesn't show any signs of wear
[01:48:42] <jmkasunich> brick sh_thouses
[01:48:43] <cradek> I guess it's had the belt replaced once too
[01:49:11] <cradek> yeah even the racks aren't rusty, the rubber coating is all intact
[01:49:14] <jmkasunich> our dishwasher is about 14 years old, and I've had to repair it twice
[01:49:27] <cradek> unlike my newer one at home which is rusting to pieces
[01:49:41] <jmkasunich> once the float switch that turns off the water during fill was corroded, the other time a door spring broke
[01:50:07] <cradek> it's fun to fix stuff that was made to be fixed
[01:50:37] <skunkworks> sorry. Depends on how some medium sized servos work.
[01:51:19] <jmkasunich> dc brush servos?
[01:51:22] <skunkworks> es
[01:51:23] <skunkworks> yes
[01:52:58] <skunkworks> In the back of my mind I think I am going to add some simple current limit to the circuit.
[01:53:07] <jmkasunich> thats a good idea
[01:53:20] <jmkasunich> prevents popping fets in the event of a short or something
[01:54:07] <skunkworks> I have 45 of them. :) lots of oopses. I will need them.
[01:55:17] <skunkworks> (please don't lump me in with bo^dick)
[01:55:26] <jmkasunich> heh
[01:57:03] <cradek> that scheme sure works on my small machine
[01:57:17] <cradek> it'll be interesting to see what you can do
[01:58:00] <jmkasunich> I have dreams of doing an AC drive using computer controlled PWM (not software, more like Jon's UPC, or a m5i20, or something like that
[01:58:03] <cradek> with pwm it's hard to both keep the frequency up AND get a lot of different levels
[01:58:22] <jmkasunich> I have a _large_ AC servomotor that I'd like to use as a spindle drive for my lathe
[01:58:53] <jmkasunich> 4000 oz-in
[01:59:07] <skunkworks> nice
[01:59:43] <jmkasunich> unfortunately I'll have to hack up a drive for it
[02:02:58] <jmkasunich> before I get into that I need to figure out how I'm going to deal with wires
[02:03:07] <jmkasunich> packaging CNC stuff (drives, etc) is a pain
[02:03:14] <skunkworks> whats up with the wires?
[02:03:21] <skunkworks> ah
[02:03:34] <jmkasunich> well right now its just the tip of the iceberg - I need to replace a blown run cap on the lathe motor
[02:03:54] <jmkasunich> to get at the motor I need to remove a chunk of housing, but the power switches are mounted on that
[02:04:02] <jmkasunich> and wired to the motors
[02:04:12] <jmkasunich> so its all unbolted, but still tied down by wires
[02:04:35] <jmkasunich> which are terminated in tiny, unlabeled, crappy, chinese terminal blocks
[02:04:56] <jmkasunich> I don't want my CNC project to end up like that
[02:05:41] <jmkasunich> I want to be able to remove any part (electronics box, motor, etc) without fscking around with wires
[02:06:28] <skunkworks> bluetooth :) with electro-magnetic coupling for power.
[02:06:57] <jmkasunich> ;-)
[02:07:00] <skunkworks> are you thinking lots of plugs?
[02:07:28] <jmkasunich> probably
[02:08:01] <jmkasunich> trying to remember how the mazak handled that kind of thing
[02:08:10] <jmkasunich> not all the well IIRC
[02:08:50] <jmkasunich> liquidtite flexible conduit with discrete wires in it mostly
[02:09:27] <jmkasunich> and little conduit boxes on things like limit switches
[02:13:37] <skunkworks> I remember seeing a lot of blue wires run externally ;)
[02:14:33] <cradek> I found it hard to believe how complex that machine was
[02:14:35] <cradek> is
[02:14:58] <jmkasunich> heh, its a lot simpler than it _was_
[02:15:09] <jmkasunich> we simply ignored a lot of I/O
[02:15:35] <jmkasunich> things like "fuse F23 just blew" inputs to the control
[02:16:12] <jmkasunich> skunkworks: I don't think there were any external blue wires
[02:16:45] <jmkasunich> lots of wires in wiring troughs and such, with the covers removed
[02:17:02] <cradek> there was lots of blue wire that had been pulled from it I think
[02:17:04] <jmkasunich> but if the machine was buttoned back up I think everything was inside either metal or conduit
[02:17:12] <jmkasunich> yes, lots and lots of that
[02:17:52] <jmkasunich> pull out a one end of a bundle of 50 wires, then buzz it out and connect the 20 wires we cared about
[02:18:06] <jmkasunich> the other 30 were probably still hanging there, but in the long run they'd be removed
[02:18:46] <skunkworks> http://www.electronicsam.com/images/KandT/cncworkshop/mazake2.JPG
[02:18:57] <skunkworks> :) notice the wires on the left
[02:18:58] <jmkasunich> I just remembered something I saw on the web - clever way to deal with oil and chips, but not with disconnecting for service
[02:19:31] <jmkasunich> hose barbs and clear vinyl hose, as a substiture for small diameter liquidtite conduit
[02:19:58] <jmkasunich> yeah, thats a bundle thats not buzzed out yet
[02:20:37] <skunkworks> thats ok - makes me feel beter about my projects :)
[02:20:39] <jmkasunich> http://www.electronicsam.com/images/KandT/cncworkshop/mazake1.JPG
[02:21:14] <jmkasunich> the bundle in the lower right (next to somebody's shoulder in a purple shirt) is the one you saw in the other pic
[02:21:36] <jmkasunich> that end is coming from a conduit and entering the compartment, the free end is draped over the open door in the other pic
[02:21:52] <jmkasunich> the upper right is another bundle, the free end of that one is draped the other direction
[02:27:43] <jmkasunich> I like the sherline approach to stepper wiring
[02:29:24] <skunkworks> I don't like plugs.
[02:29:35] <jmkasunich> why not?
[02:30:06] <skunkworks> Unless they are mondo expensive cannon plugs - I have had bad luck.
[02:31:18] <skunkworks> (plus all I work on is old machines :))
[02:31:25] <jmkasunich> I'd scrounge around for good plugs
[02:31:55] <jmkasunich> a _good_ terminal block (with ring lugs on the wires, and everything labeled) is OK too
[02:32:13] <jmkasunich> but its got to be sealed up to keep chips and crap out
[02:32:28] <skunkworks> right
[02:32:35] <jmkasunich> so then the drill is
[02:32:40] <jmkasunich> 1) remove lid from terminal box
[02:32:44] <jmkasunich> 2) disconnect wires
[02:33:02] <jmkasunich> 3) disconnect liquidtite or whatever from conduit box
[02:33:14] <jmkasunich> all that just to separate one part from another
[02:35:01] <jmkasunich> the other thing I need to figure out is exactly where I want to put my electronics box
[02:35:31] <jmkasunich> theres no free space on/under the bench that holds the machine
[02:36:29] <jmkasunich> I could maybe mount the box on the back of the bench, but access would be horrible
[02:36:46] <jmkasunich> and it would have chips landing on it all the time
[02:37:19] <jmkasunich> cradek: did you ever wire up your machine to use that cannon connector you bought at the fest?
[02:37:41] <cradek> no, maybe next time it's apart
[02:38:10] <cradek> I often under-engineer things and then don't mess with them as long as they work
[02:38:52] <cradek> that stepper drive setup is a prime example... ugly but sure makes the mill go
[02:39:37] <cradek> the lathe needs attention first - the wiring and drivers are all exposed so a chip in the wrong place is bad news
[02:40:07] <jmkasunich> so you have the same issues I'm tangling with, only on a smaller scale
[02:40:19] <cradek> yeah
[02:40:33] <cradek> you remember the motors with exposed encoders on the ends
[02:40:46] <jmkasunich> kinda
[02:40:50] <cradek> I haven't figured out how to cover all that
[02:40:53] <jmkasunich> I don't recall exactly how exposed
[02:41:02] <cradek> completely exposed circuit board
[02:41:07] <jmkasunich> hmm
[02:41:16] <cradek> and you can see the encoder disk if you look just right
[02:41:18] <jmkasunich> did you post pics of your setup once?
[02:42:52] <cradek> http://timeguy.com/cradek/emc
[02:43:00] <cradek> it has to be here but I'm not spotting it
[02:43:21] <cradek> http://timeguy.com/cradek-files/emc/DSCN6290.JPG
[02:43:23] <cradek> aha
[02:44:15] <jmkasunich> I see
[02:44:59] <cradek> I'm tempted to get a heavy latex balloon and stretch it over the end of the motor and call it good
[02:45:13] <jmkasunich> you can rotate the motor by 90 degree increments, right?
[02:45:43] <cradek> there might be two orientations that are acceptable on this axis
[02:45:48] <jmkasunich> you'll have a hard time stretching the mouth of the balloon big enough to pass the PC board
[02:45:55] <cradek> the other one can't be rotated
[02:46:24] <cradek> yeah, couldn't use exactly a balloon, but something like that
[02:46:43] <jmkasunich> plastic bag and cable-tie?
[02:46:52] <cradek> yeah maybe so
[02:46:59] <jmkasunich> I assume you replaced the flat cable with something else?
[02:47:01] <cradek> doesn't have to be pretty, just has to work
[02:47:12] <cradek> yes wiring is all replaced
[02:48:24] <cradek> ideally the belts would be protected too but that's much less critical
[02:48:53] <jmkasunich> the motor mount plate is 1/4" thick?
[02:49:13] <cradek> I think each piece is 3/16
[02:49:18] <jmkasunich> oh
[02:49:22] <jmkasunich> kinda thin then
[02:49:29] <jmkasunich> I was thinking of drilling and tapping the edge
[02:49:48] <cradek> maybe it is 1/4
[02:50:02] <cradek> the big cap screw is 10-xx
[02:50:12] <jmkasunich> then taking a sheet of thin aluminum (like flashing - maybe 0.010 or so) and forming it into a oddly shaped tube
[02:50:18] <jmkasunich> the plate would be one end-cap of the tube
[02:50:23] <jmkasunich> the other end would be out by the encoder
[02:50:44] <jmkasunich> if you're really lucky, the encoder board footprint fits inside the mounting plate footprint
[02:50:58] <cradek> I see what you mean
[02:51:11] <cradek> another complexity is the pulley sticks above the top of the table/mount
[02:51:21] <jmkasunich> the pulley flange does
[02:51:28] <jmkasunich> that can be fixed ;-)
[02:51:35] <cradek> yeah maybe it's just the flange and not the belt
[02:51:48] <cradek> I think I'll get a plastic bag and wire tie :-)
[02:51:56] <jmkasunich> lol
[02:52:09] <cradek> it's fitting with the rest of the lathe setup
[02:52:12] <cradek> minimalist
[02:52:21] <cradek> or janky, depending on your point of view
[02:52:27] <jmkasunich> heh
[02:52:38] <jmkasunich> well, I need to be a little better
[02:52:50] <jmkasunich> because I scatter a lot more chips over a lot wider area
[02:53:07] <jmkasunich> and some of them are hot enough to melt the plastic bag
[02:53:47] <cradek> yeah that sounds a little different
[02:54:01] <cradek> I've made hot chips with the mill but not many
[02:54:18] <cradek> I'm pretty conservative with it, don't want to break anything
[02:54:24] <jmkasunich> I was looking for our digicam, wanted to post a pic of my machine with the cover off
[02:54:29] <jmkasunich> chips everywhere
[02:57:09] <cradek> haha http://timeguy.com/cradek-files/emc/fuglui.png
[02:58:39] <jmkasunich> ;-)
[03:00:39] <skunkworks> time for bed. you guys have fun.
[03:00:45] <cradek> g'night
[03:00:51] <jmkasunich> goodnight
[03:00:57] <jmkasunich> found the camera
[03:01:00] <skunkworks> night
[03:02:38] <cradek> the images in this directory tell so many stories about emc and other things
[03:02:48] <cradek> they go back quite a while, I never clean them up
[03:08:27] <jmkasunich> pic from our trip: http://home.att.net/~jmkasunich/Pics/mattie_rail.JPG
[03:08:56] <cradek> a visitor or your traveling companion?
[03:09:13] <jmkasunich> a visitor
[03:09:27] <jmkasunich> belongs to the director of the nature preserve, who lives in the other half of the house
[03:09:37] <jmkasunich> http://home.att.net/~jmkasunich/Pics/fern.JPG
[03:09:42] <jmkasunich> on a rock wall
[03:09:43] <cradek> oh was this your anniversary thing? how was that?
[03:09:49] <jmkasunich> very nice
[03:12:36] <jmkasunich> http://home.att.net/~jmkasunich/Pics/porch.JPG
[03:13:10] <jmkasunich> its very green there ;-)
[03:13:32] <cradek> that porch and coffee in the morning would be pretty darn nice.
[03:13:50] <jmkasunich> I'll skip the coffee, but yes
[03:14:10] <jmkasunich> the pic doesn't convey the sounds
[03:14:15] <jmkasunich> birds, bugs, and running water
[03:15:21] <cradek> what does your wife do for fun? not a machinist too I assume
[03:15:43] <jmkasunich> no
[03:15:50] <jmkasunich> she is a bench jeweler
[03:16:06] <cradek> neat, a different way of building stuff
[03:16:14] <cradek> does she do casting etc?
[03:16:30] <jmkasunich> http://home.att.net/~jmkasunich/Pics/purple.JPG
[03:16:35] <jmkasunich> not at home
[03:16:45] <jepler> cradek: hah, nobody ever "improved" on fuglui
[03:16:48] <jepler> I can't say I blame them
[03:16:55] <cradek> I've always wanted to try that but have no idea what I'd do with any jewelry
[03:17:02] <jmkasunich> jepler: late, but as promised, I'm posting pics of our trip
[03:17:03] <cradek> jepler: it was done, wasn't it?
[03:17:36] <jmkasunich> "purple" came out pretty nice, given a point-n-shoot digicam
[03:17:40] <cradek> looks done to me, totally configurable
[03:17:54] <cradek> yeah, and I don't recognize that flower
[03:19:09] <jmkasunich> http://home.att.net/~jmkasunich/Pics/greenrock.JPG
[03:20:22] <jmkasunich> the biggest darn millipede I've ever seen - 2-1/2" long (maybe 3")
[03:20:23] <jmkasunich> http://home.att.net/~jmkasunich/Pics/millipede.JPG
[03:22:57] <cradek> those things are cool
[03:23:04] <cradek> from another planet, but cool
[03:25:35] <jmkasunich> http://home.att.net/~jmkasunich/Pics/goat.JPG
[03:25:53] <jmkasunich> we were walking along the road back to the house, and we heard a "clunk"
[03:26:32] <jmkasunich> "what was that?" start looking around, then look thru the bushes and see a face staring at us between the fence rails - the clunk was his horns hitting the fence when he tried to look thru
[03:27:06] <cradek> darn horns always getting in the way
[03:27:44] <cradek> the other day I saw goats standing up on their hind legs to eat tree leaves - is that usual? (I'm a city kid)
[03:27:56] <jmkasunich> I think so
[03:28:02] <cradek> it seemed like an unlikely sight at the time
[03:28:41] <jmkasunich> trying to decide what other pics to post
[03:28:47] <jmkasunich> got more of mattie
[03:28:51] <jmkasunich> some flowers
[03:29:08] <jmkasunich> couple of the interior of the hose
[03:29:09] <jmkasunich> house
[03:29:34] <jmkasunich> grasshopper on a tree ;-)
[03:30:56] <jmkasunich> http://home.att.net/~jmkasunich/Pics/grasshopper1.JPG
[03:31:22] <cradek> < jmkasunic> I was looking for our digicam, wanted to post a pic of my machine with the cover off
[03:31:36] <jmkasunich> lol
[03:31:51] <cradek> more millipedes there on the left
[03:31:58] <jmkasunich> ok, this is the last trip pic
[03:31:58] <jmkasunich> http://home.att.net/~jmkasunich/Pics/bedroomdoor.JPG
[03:32:20] <jmkasunich> you are joking I assume
[03:32:31] <jmkasunich> oops, you're not
[03:32:33] <cradek> ?
[03:32:46] <cradek> oh you must not have noticed them
[03:32:46] <jmkasunich> I didn't see the millipede, thought you were referring to the vines and their rootlets
[03:33:03] <jmkasunich> them? I see one
[03:33:13] <cradek> oh maybe it is one long one
[03:33:43] <cradek> jeez, I'm not so much of a city kid that I can't tell a vine from a millipede
[03:34:02] <cradek> reminds me of the 'guess the animal' game
[03:34:22] <cradek> "and what is a question that would distinguish a millipede from a vine?"
[03:34:28] <cradek> "and the answer for millipede would be what?"
[03:36:39] <jmkasunich> is it moving?
[03:37:20] <jmkasunich> http://home.att.net/~jmkasunich/Pics/lathemotor.JPG
[03:38:31] <jmkasunich> http://home.att.net/~jmkasunich/Pics/lathebeltbox.JPG
[03:39:07] <jmkasunich> theres a few chips on the motor
[03:39:26] <cradek> I see that
[03:39:45] <jmkasunich> the clean spot is where the box used to be
[03:41:03] <jmkasunich> I'd like to replace the box
[03:41:04] <cradek> yeah you're going to have to protect everything pretty well
[03:41:27] <jmkasunich> put a 3/8" or so aluminum plate against the end of the machine (where the 1/16" box back used to be)
[03:41:28] <cradek> can't you stick a computer to the left? looks like a nicely sized empty spot
[03:41:35] <jmkasunich> and mount the new motor to the plate
[03:41:57] <jmkasunich> it would have to be movable, because there is a cabinet there
[03:42:09] <jmkasunich> you can just see the door handle in the top left of the beltbox pic
[03:42:31] <cradek> oh I see it, I mistook that for a wall
[03:42:39] <cradek> the paint job tricked me
[03:42:50] <jmkasunich> the colors are terrible
[03:43:03] <cradek> I've seen worse
[03:43:06] <jmkasunich> the former owners of the house really liked yellow
[03:43:11] <cradek> I've seen worse indoors
[03:43:24] <jmkasunich> I've repainted part of the basement walls to a light gray, but not behind the machine
[03:43:34] <cradek> I like yellow, it's the brown-purple that's a bit wild for my taste
[03:43:40] <jmkasunich> too much work to move it (700 lbs, not counting the bench and all the crap in it)
[03:44:02] <jmkasunich> the floor is the same color as the lower part of the wall :-(
[03:44:11] <cradek> paint is not important.
[03:44:21] <cradek> colors are all arbitrary
[03:44:32] <jmkasunich> lighter colors do make the room brighter
[03:44:39] <jmkasunich> handy in a basement
[03:45:05] <cradek> true, light is good
[03:45:07] <jmkasunich> in the long run I want to completley redo the lathe drivetrain
[03:45:14] <cradek> crap it got late again
[03:45:34] <jmkasunich> get rid of the v-belts, and have 2 or three speeds, each about a 3:1 step
[03:46:02] <jmkasunich> use variable motor speed between the ranges, only change the belt when very low speed and high torque are needed
[03:48:15] <jmkasunich> damn, I forgot - I'm gonna have to move the machine anyway to CNC it
[03:48:32] <jmkasunich> the Y motor will stick out the back of that box that is on the rear of the table
[03:48:51] <jmkasunich> (the box that ends up 1/4" from the wall when Y is all the way back right now)
[03:49:30] <jmkasunich> this is why I've been doing my conversion for 3 years and made almost no progress
[03:53:29] <cradek> I hope when you finally get started it will go fast because you have spent a lot of time planning
[03:53:43] <jmkasunich> I hope so
[03:53:52] <jmkasunich> but things like moving the machine will take time regardless
[03:54:15] <jmkasunich> I dunno if I should move it straight away from the wall by 6", or turn it 90 degrees and put the tailstock end to the wall
[03:54:48] <jmkasunich> another possibility is to drop the crank handle on Y and put the motor on the front
[03:55:14] <cradek> can you move it with a floor jack or pallet jack and ingenuity, or does it take more?
[03:55:16] <jmkasunich> but that would wind up obstructing the tee-slots, making it hard to insert t-nuts or remove chips
[03:55:33] <jmkasunich> the bench is wood
[03:55:40] <jmkasunich> strongly constructed wood, but still wood
[03:55:52] <cradek> oh I see that now
[03:55:53] <jmkasunich> so I'm hesitant to move it from underneath
[03:56:19] <jmkasunich> the original install went like this:
[03:56:24] <jmkasunich> 1) remove mill head
[03:56:30] <jmkasunich> 2) set machine under final location
[03:56:41] <jmkasunich> 3) install 4 eyebolts in joists, and block them up
[03:56:47] <jmkasunich> raise main part of machine
[03:56:55] <jmkasunich> 5) slide bench underneat
[03:57:04] <jmkasunich> 6) lower machine onto bench and bolt down
[03:57:10] <jmkasunich> 7) replace millhead
[03:58:31] <jmkasunich> if I moved the whole bench out 6", it would be tempting to stick the electronics box in back
[03:58:38] <cradek> do you use this much as a mill? it sure looks like it has a small table
[03:59:13] <jmkasunich> 6-1/2" x 19"
[03:59:38] <jmkasunich> I don't use it as a mill much right now because its not rigid enough to take heavy cuts
[03:59:51] <jmkasunich> but once CNCed, I'll use it for lighter precision work
[03:59:58] <jmkasunich> the Van Norman handles my heavy work
[04:00:40] <jmkasunich> the travels are something like 11" x 11" (depending on where the tailstock is and if the chuck is in place)
[04:02:35] <jmkasunich> "not rigid enough" is relative - compared to a sherline or maxNC or Grizzely mini-mill its pretty rigid
[04:03:25] <cradek> it definitely looks like a nice machine to have around if you only have one
[04:03:38] <cradek> I better get to bed!
[04:03:43] <jmkasunich> goodnoght
[04:03:43] <cradek> goodnight
[04:03:45] <jmkasunich> i
[04:04:20] <jmkasunich> and I better get the info on the toasted cap
[12:08:24] <jepler> jmkasunich: thanks for sharing the photos
[12:20:34] <skunkworks> logger_devel: bookmark
[12:20:34] <skunkworks> See
[19:13:20] <alex_jon1> alex_jon1 is now known as alex_joni