#emc | Logs for 2008-11-20

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[00:07:47] <JymmmEMC> * JymmmEMC makes electrified iron leggings for bigjohnt's wandering problem
[00:12:01] <dmess> Big J's history lesson is accurate and acknowledged... ;)
[00:12:56] <dmess> learn ti file before you jump on a cnc... it'll be worthit
[00:19:01] <jepler> skunkworks: starting over on the layout?
[00:19:34] <skunkworks> http://imagebin.ca/view/RBqYRa.html
[00:19:51] <skunkworks> a bit. I need to make it a little tighter.
[00:20:32] <skunkworks> I love the way jmk make the power-handling traces
[00:20:55] <skunkworks> *made
[00:22:12] <skunkworks> biab
[00:23:27] <skunkworks> (This has the driver gnd hooked to the mosfets.
[00:23:28] <skunkworks> )
[00:23:55] <skunkworks> I still am not sure about that.. Like what happens if the voltage across the resistor goes negative.
[00:48:12] <dmess> POOF is my buest guess....
[02:16:00] <john_f> Hey, This is not really a CNC machine question but has anyone used an automatic boring / facing head?
[02:36:01] <SWPadnos> heh: http://idle.slashdot.org/article.pl?sid=08/11/18/1729224
[02:44:07] <SWPadnos> http://www.theonion.com/content/video/in_the_know_should_the_government?utm_source=videomrss_89550
[02:45:00] <dmess> J F yes numourous times... whats your question??
[02:45:35] <john_f> how to use one
[02:46:05] <dmess> automatic can be mechanical OR electronic??
[02:46:44] <dmess> program a u or w axis... what machine?
[02:47:03] <john_f> This one is mechanical.
[02:47:20] <john_f> Enco
[02:47:37] <dmess> so what axis is the quill that it hooks up to
[02:48:14] <dmess> enco are usually small stuff.... how big?
[02:48:19] <john_f> It is boring head but if you hold the top while it is spinning the tool moves outward
[02:48:48] <john_f> For a vertical milling machine
[02:49:13] <john_f> maybe 3 to 4 " dia
[02:49:14] <dmess> manual boring and facing head... needs a stop rod
[02:49:51] <dmess> i see... sweet did you get it cheap??
[02:50:33] <john_f> so the stop rod extends from the part that you keep from spinning with the spindle?
[02:50:59] <dmess> yes..
[02:51:01] <john_f> yes I acquired it
[02:51:24] <john_f> I don't see a place to insert the stop rod
[02:51:27] <dmess> slick... acquire 1 for me.... LOL
[02:52:00] <john_f> but the top part is knurrled(sp?)
[02:52:51] <john_f> you can make it move at three different rates per rev
[02:52:58] <dmess> there should be a tapped hole on the upper part of the head to take a stickout rod??
[02:53:16] <Gamma-x> what is needed in a machine for rigid tapping?
[02:53:36] <dmess> a spindle encoder
[02:54:01] <dmess> the spindle has to become an axis
[02:54:20] <Gamma-x> hmmm
[02:54:26] <Gamma-x> i wonder how i do that lol
[02:54:34] <dmess> dont hmmm me
[02:54:54] <Gamma-x> lol
[02:55:30] <dmess> ive heard it too many times NOT to use it :)
[02:56:21] <Gamma-x> it seems so useful though
[02:56:47] <SWPadnos> for rigid tapping, you need a reasonable resolution encoder with index on the spindle, and you need to be able to control the spindle direction (and ideally speed)
[02:57:09] <dmess> pulse encoder SHOULD work... i haven't gotten mine going yet..
[02:57:17] <SWPadnos> not for rigid tapping
[02:57:37] <SWPadnos> if you're talking about 1-PPR (index only) feedback
[02:58:05] <dmess> no.. rigid.. is servo/spindle control
[02:58:11] <Gamma-x> did the encoders that are exact count, are they workin with emc yet?
[02:58:44] <SWPadnos> dmess, no, you don't need servo control of the spindle, just good feedback and a Z servo that can handle the acceleration demands
[02:58:46] <dmess> i havent wired them yet..
[02:59:10] <SWPadnos> Gamma-x, are you referring to absolute encoders?
[02:59:18] <Gamma-x> yes sir
[02:59:31] <SWPadnos> then no, there's no specific support for them yet
[02:59:51] <SWPadnos> it may be possible to write code that would fake it, but it's not written yet
[03:00:01] <dmess> i believe toshiba only needed a z-axis encoder
[03:00:04] <Gamma-x> not worth it to me. id rather have a reliable machine
[03:00:18] <Gamma-x> how about the spindle break.
[03:00:37] <Gamma-x> if i have a vfd is it worth it to buy a spindle break.. like a breaking resistor
[03:00:37] <Gamma-x> ?
[03:00:53] <dmess> NO
[03:00:55] <SWPadnos> it's best to not break your spindle :)
[03:00:59] <SWPadnos> but braking is OK :)
[03:01:09] <Gamma-x> braking* haha sorry
[03:01:10] <dmess> i have a brake AND a vfd
[03:01:17] <Gamma-x> dmess, u like it?
[03:01:26] <SWPadnos> they're meant for different things
[03:01:40] <SWPadnos> a VFD braking resistor can only slow the spindle down faster, it's a load dump
[03:01:49] <dmess> it isnt running yet... i cant finger out the config
[03:01:52] <SWPadnos> it doesn't prevent it from moving like a physical brake does
[03:02:08] <Gamma-x> ahhh
[03:02:13] <Gamma-x> i thought it stopped the motor
[03:02:18] <SWPadnos> and a physical brake isn't usually used to stop the motor, AFAIK
[03:02:33] <SWPadnos> it's not like they have replaceable brake pads or anything
[03:02:40] <SWPadnos> (again, AFAIK)
[03:02:56] <Gamma-x> i think it has a brake
[03:02:59] <dmess> i have a $750 brake in a box
[03:03:07] <Gamma-x> an air break. i just need to configure that actuator into emc
[03:03:17] <SWPadnos> what's more useful is a Z axis brake, so when you E-Stop, it stops the quill/knee (or whatever) from falling
[03:03:53] <SWPadnos> there's a brake signal, and if you compile TRUNK, there are other signals that can be used to control when the spindle moves after a speed change or the like
[03:03:58] <dmess> and SLAMM into the bottom end of the scre and get STUCK
[03:04:08] <dmess> screw
[03:04:09] <SWPadnos> err, to control when EMC starts motion again, after a spindle speed change
[03:04:22] <Gamma-x> SWPadnos, u reffering to a limit switch on the z axis?
[03:04:26] <SWPadnos> or worse, slam into someone's arm after they hit E-Stop
[03:04:29] <SWPadnos> no, a brake
[03:04:40] <Gamma-x> sorry kidna confused on the z axis brake.
[03:05:13] <SWPadnos> if you have a counterbalanced quill (which you likely do on your bridgeport/clone), then it's not all that important
[03:05:27] <dmess> i had my knees taken out by a Hermle splash pln
[03:05:41] <SWPadnos> sounds painful
[03:06:46] <dmess> ended up with a 4x4x6 inch block of jackpine as a bumper stop
[03:07:22] <dmess> stop drop and roll when it happened
[03:09:50] <Gamma-x> SWPadnos, i have a supermax...
[03:10:01] <SWPadnos> right - close to a Bridgeport
[03:10:03] <SWPadnos> IIRC
[03:10:09] <SWPadnos> a YTM-5 or something
[03:11:28] <Gamma-x> ycm-18
[03:11:39] <Gamma-x> wich is pretty much the same as a ycm-40 with older control...
[03:11:46] <dmess> you should only need an encoder of reasonable resolution and to tune the z drive to match it
[03:11:49] <SWPadnos> well, at least I had the Y and M and the dash right :)
[03:13:06] <dmess> ive done 1"-8 x 8 dp... and pecked it out ;)
[03:13:31] <Gamma-x> got it
[03:13:41] <Gamma-x> 3 hp 3 phase on a vfd so about a 2hp motor.
[03:14:12] <dmess> wow mine is 0.5 hp
[03:14:18] <Gamma-x> spindle brake. power draw bar, auto lube, coolant taper #40 ns i believe. 49 x 9 table
[03:14:45] <Gamma-x> and at the time a working anilam with 27 pnd servos,
[03:14:52] <Gamma-x> all for 2 grand
[03:14:52] <dmess> are you modeling this?
[03:14:59] <Gamma-x> haha
[03:15:40] <dmess> hey... i havent modeled my hardinge
[03:16:18] <dmess> you have HAL handling it all yet
[03:16:50] <Gamma-x> my table jsut seems to run away lol
[03:19:11] <dmess> http://www.youtube.com/watch?v=j_zPXtaGTQs&feature=related this will sooth your mind
[03:23:52] <Gamma-x> http://www.youtube.com/watch?v=Ddn4MGaS3N4
[03:23:56] <Gamma-x> this tends to sooth my soul
[03:24:00] <Gamma-x> keep it on a medium volume
[03:30:41] <jmkasunich> wow - http://www.youtube.com/watch?v=e_P_-cFbGbU&feature=related
[03:39:13] <SWPadnos> man, he's pretty darned good
[03:45:46] <JymmmEMC> I can do that <rolls eyes>
[03:46:25] <SWPadnos> so can I, but it doesn't sound as good :)
[03:46:34] <JymmmEMC> tooshey
[03:46:57] <SWPadnos> I was looking for some good quality recording with Leo Kottke, and this is all I found that I like: http://www.youtube.com/watch?v=wQKbwLqKEOI
[03:47:16] <HAL9000> HAL9000 is now known as SkinnYPupp_
[03:47:49] <SWPadnos> (well, I like a lot of the other songs he plays, but a lot of the videos are handheld balir witch quality)
[03:47:54] <SWPadnos> blair
[03:58:39] <JymmmEMC> witch
[04:00:40] <SWPadnos> a different take on "Stairway To Heaven": http://www.youtube.com/watch?v=HjXN3OLgoqs&feature=related
[04:00:43] <SWPadnos> (one I like)
[04:01:21] <cradek> http://www.youtube.com/watch?v=P07Di283vfw
[04:02:55] <jmkasunich> cradek: wtf?
[04:03:20] <cradek> a different take on "music"
[04:03:26] <cradek> I thought it was hilarious
[04:03:46] <jmkasunich> quite a contrast from Tommy Emmanual
[04:04:15] <cradek> I didn't look at any of the others yet - firefox upgrade running
[04:04:17] <SWPadnos> man, I didn't realize that Jordan plays two guitars at once O_O
[04:09:19] <SWPadnos> cradek, that is a "different" take on "music"
[06:59:14] <renesis> holy shit
[06:59:40] <renesis> that guy is doing rythem and lead parts at once
[06:59:55] <renesis> like jimi
[06:59:58] <renesis> !
[07:01:49] <renesis> jes hes def from another planet like jimi
[12:54:15] <fragalot> http://i4.photobucket.com/albums/y127/BrissyMonk/ChopperOne_RSide_Front_LG.gif *wants*
[12:58:45] <BigJohnT> what is it?
[12:59:07] <archivist> chopped pc
[12:59:09] <BigJohnT> update manager has the string busy so I can't go look
[12:59:49] <archivist> you need more than wet string BigJohnT
[12:59:50] <BigJohnT> cool
[13:00:18] <BigJohnT> well we have tin cans at each end...
[13:00:25] <fragalot> BigJohnT: it's a pretty awesome chopper PC case
[13:00:34] <archivist> get them gold plated
[13:02:40] <BigJohnT> 1m30s
[13:05:07] <BigJohnT> nice... and easy to blow the dust out
[13:06:12] <BigJohnT> how much?
[13:06:21] <fragalot> good Q
[13:08:20] <BigJohnT> well time to go
[13:52:32] <jepler> archivist: while I don't doubt that "casemod" requires a lot of skill, I still can't manage to like it.
[13:52:41] <jepler> fragalot: ^^ er, that was directed to you
[13:53:15] <fragalot> jepler: personal opinions. You are entitled to your own, but i admire the work put into it :)
[13:54:09] <cradek> the 'radiator' is neat, and possibly even useful
[13:54:25] <fragalot> Aye
[13:54:27] <cradek> however one reason for a computer case is to keep the cats out, and this one seems to fail at that
[13:54:37] <fragalot> cradek: you could just put plexi on the sides
[13:54:45] <fragalot> screws that could be used for that are already in place
[14:54:15] <Paragon> Hello Everyone....
[14:56:43] <Paragon> Just took the plunge and bought a Boxford AUD http://www.lathes.co.uk/boxford/page2.html Lathe and Beaver Mill http://www.lathes.co.uk/beaver/page5.html from Home Workshop Machinary.
[14:57:15] <toastatwork> does anyone have a vim syntax thing for gcode
[14:57:55] <toastatwork> also nice purchases, paragon
[15:01:13] <Paragon> toastatwork: I've been meaning to upgrade my Granville for some years now but kept on putting it off I've never owned a manual mill so this is my first. It's just the right size for my workshop due to space constraints. Got some bad news today so thought sodit go for it :-)
[15:03:44] <archivist> heh so you about to get the level to fix the Granville and its retired
[15:05:48] <archivist> hmm Bridgeport seems cheap at the moment
[15:05:51] <archivist> http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=280284293224
[15:06:43] <archivist> I want a cnc one though so it already has servos etc
[15:07:05] <cradek> wow that looks like a well-used and then well-rotted machine
[15:07:19] <cradek> "I WILL TRY TO WIRE IT UP BEFORE LISTING ENDS. THERE IS NO REASON IT DOESNT WORK"
[15:11:51] <Paragon> archivist: Yep the Granville is retiring. Though the level will come in handy for the new lathe :-)
[15:12:19] <archivist> what I should go for http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=290274520486
[15:13:03] <Paragon> I've now got to go rip out the work top that I just built out of 2X4 to make room for them :-(
[15:16:53] <Paragon> I have a question regarding inverters or 3 phase conversion. The mill has a 1hp 3ph drive motor a 3ph powered table and 3ph suds. The lathe has 3ph .075 hp and a small 3ph suds motor. I guess I need to buy two digital inverters but I saw mentioned that the suds and the power feed are small so a cap can be introduced to drive them from 240v single. Is this the best way to go and how do I...
[15:16:54] <Paragon> ...workout the size of capacitor for the motors?
[15:16:59] <archivist> ah well, adjust walls
[15:17:16] <Paragon> Tried that ;-)
[15:19:47] <archivist> Capacitor depends on motor
[15:20:03] <cradek> Paragon: I did that recently with my lathe's coolant/oil motor. it is 1/6 HP and it took quite a bit (about 16 uF?) of motor run capacitors
[15:20:40] <cradek> I adjusted the capacitance until it seemed to start reliably (takes more capacitance) but the current in any of the three wires wasn't (much) over the motor rating
[15:21:04] <cradek> (it feels like a juggling act and is a fairly poor solution to the problem)
[15:21:36] <jepler> cradek: and you just happened to have a bunch of spare x00V capacitors in the uF range to test with?
[15:21:51] <Paragon> Especially if I need to do it for 3 motors...
[15:22:03] <jepler> you people with overdeveloped junk boxes make me envious
[15:22:03] <cradek> yes, they're not expensive, the metal can type
[15:22:19] <archivist> junk!!!!
[15:22:24] <archivist> neva
[15:22:44] <archivist> might be useful TM
[15:23:06] <cradek> NB: motor RUN capacitors, not motor START capacitors
[15:23:13] <Paragon> Is there a calculation for it or is it more a trial an error thing?
[15:23:26] <toastatwork> nobody has a vim file for gcode highlighting?
[15:23:35] <cradek> toastatwork: check the emc-users archives
[15:23:40] <toastatwork> where is that?
[15:23:50] <cradek> Paragon: google told me a rule of thumb, I forget what it was
[15:24:10] <cradek> http://news.gmane.org/gmane.linux.distributions.emc.user
[15:24:16] <toastatwork> ty
[15:24:18] <Paragon> cradek: No worries Ill search our best freind ...
[15:25:43] <cradek> Paragon: lots of jmkasunich helping me with it here: http://www.linuxcnc.org/irc/irc.freenode.net:6667/emcdevel/2008-10-15.txt
[15:26:23] <Paragon> What do you think about using one inverter and have a switch to change between mill and lathe motor? I would only be using one machine at a time.
[15:26:39] <cradek> that does not sound like a problem
[15:26:43] <Paragon> Thanks cradek
[15:26:47] <cradek> having one big enough to run both seems nice though
[15:28:25] <SWPadnos> not with a VFD
[15:28:30] <SWPadnos> one motor per VFD
[15:28:33] <Paragon> Problem is that the digital inverters are designed to be used for one motor at a time. So I would need to switch the output of the inverter to what ever machine I wish to use
[15:28:55] <SWPadnos> is that what you mean by inverter, a variable frequency drive?
[15:29:06] <SWPadnos> that's not the only problem
[15:29:06] <Paragon> SWPadnos: Yes it is
[15:29:21] <Paragon> Is it torque tuning as well?
[15:29:28] <SWPadnos> you also need to tune the VFD for the motor
[15:29:47] <cradek> oh I didn't understand you meant VFD
[15:29:55] <cradek> I thought you mean a phase converter
[15:30:01] <Paragon> I thought that may have been the case.
[15:30:03] <archivist> there are two animals a vfd (which is an inverter anyway) and a fixed freq inverter
[15:30:06] <SWPadnos> that's one advantage of a rotary phase converter :)
[15:30:36] <cradek> get a bigass 3 phase motor from a junk dealer - put a pulley on it and spin it with a cheapo 1 phase motor to start it
[15:30:37] <archivist> and two types of rotary
[15:30:41] <Paragon> These things http://cgi.ebay.co.uk/NEW-1-2HP-240V-SINGLE-TO-3-PHASE-INVERTER-CONVERTER_W0QQitemZ400009336917QQcmdZViewItemQQptZUK_BOI_Industrial_Automation_Control_ET?hash=item400009336917&_trksid=p3286.c0.m14&_trkparms=72%3A1301|66%3A2|65%3A12|39%3A2|240%3A1318
[15:30:44] <cradek> no funny capacitors to deal with
[15:31:26] <skunkworks> * skunkworks has been lucky to always have 3 phase to play with.
[15:31:48] <Paragon> Thats probable the cheapest way cradek is there any draw back from that method though?
[15:31:56] <SWPadnos> this is more or less the one I built: http://www.metalwebnews.com/howto/phase-converter/phase-converter.html
[15:32:06] <cradek> Paragon: no, actually I think it's one of the best solutions
[15:32:17] <SWPadnos> the "wild leg" often has a vastly different voltage on it unless you add run caps
[15:32:40] <SWPadnos> (using cradek's approach, not the one I linked)
[15:32:44] <cradek> SWPadnos's is similar except he uses a cap to start it instead of another motor
[15:33:08] <SWPadnos> a "real" rotary converter also has run caps, which keep the third leg voltage in line
[15:33:17] <skunkworks> you can pull start a 3 phase motor on single phase.... (just don't wrap yourself up in it) :)
[15:33:30] <SWPadnos> heh, use cheap string :)
[15:33:34] <skunkworks> * skunkworks should shut up.
[15:33:36] <jepler> why get a 3-phase converter when you can get a vfd, though? http://web5.automationdirect.com/adc/Overview/Catalog/AC_Drives/GS1_(120_-z-_230_VAC_V-z-Hz_Control) Only if you have no desire to control motor speed, I suppose.
[15:33:41] <cradek> that's true - a lawnmower starter would work great (and you wouldn't get hurt)
[15:34:03] <cradek> jepler: several machines with several motors each
[15:34:10] <jepler> cradek: ah, I missed that
[15:34:40] <Paragon> Pull start really ... and it will run ok?
[15:34:41] <cradek> skunkworks: it would take some knack to get it going the right speed before kicking in the power
[15:35:07] <cradek> Paragon: a motor would be better :-)
[15:35:08] <Paragon> Not the most elegant but interesting non the less
[15:35:10] <skunkworks> from what I rememeber - you don't have to get it up to speed - just get it moving
[15:35:55] <skunkworks> but it would depend on the load
[15:36:02] <cradek> when I had incorrect pulleys on mine (starting at a slightly wrong speed) it would sometimes trip the breaker - after I fixed that, it always starts
[15:36:26] <cradek> it's a very big motor though (8 HP?)
[15:37:20] <Paragon> I just noticed I have 2 x 2200uf caps could these be used?
[15:37:30] <cradek> ummm no
[15:37:36] <cradek> you need AC-rated motor run caps
[15:37:59] <cradek> you probably have electrolytics there, which would make a nice mushroom cloud
[15:38:35] <archivist> the rubber bung gets out with some force :)
[15:38:40] <cradek> http://surpluscenter.com/item.asp?UID=2008112009375811&item=22-1294
[15:38:44] <Paragon> Yeajh I am not sure what they are they are big say 5 inches high by 2.5 inches in dia
[15:38:47] <cradek> this is what a motor run cap looks like
[15:39:29] <Paragon> Oh Ok ... not to pricey either :-)
[15:40:57] <cradek> no - don't skimp and use something inappropriate - this is dangerous stuff.
[15:41:31] <anonimasu> pricey or not
[15:41:41] <anonimasu> paying to live is a nice deal.
[15:41:51] <Paragon> Agreed :-)
[15:41:53] <SWPadnos> one nice thing about a rotary phase converter is that once you get it going, it gets better as you turn more motors on
[15:42:02] <cradek> true
[15:42:13] <SWPadnos> the total motor mass keeping the phases going the right direction goes up
[15:42:17] <jymm> SWPadnos: that's what she said.
[15:42:18] <cradek> when your mill spindle is running, everything else will work better
[15:42:25] <SWPadnos> and the converter is really only used for starting
[15:42:28] <SWPadnos> right
[15:42:39] <cradek> so you could put a pull-start on the mill spindle, and it would run the other motors.
[15:42:46] <SWPadnos> so you can make a 5HP phase converter, and then go start 10 5HP motors
[15:42:50] <SWPadnos> heh
[15:43:07] <archivist> or if really rich use a motor driving an alternator
[15:43:29] <SWPadnos> or if really really rich get 3-phase service
[15:44:13] <SWPadnos> the motor:alternator thing is pretty hard actually. you don't get good intrinsic speed control with a 1-phase motor, and speed is importnat since it determines output voltage
[15:44:21] <archivist> for some UK houses thats just a trench and a meter
[15:44:46] <SWPadnos> coffee time yay!
[15:44:52] <Paragon> SWPadnos: that homemade inverter you linked to is that a rotary or static. Just that it mentions rotary but I was under the impression a rotary type used a motor. Also how much did it cost to build roughly?
[15:45:16] <SWPadnos> a rotary phase converter is a static phase converter with an idler motor
[15:45:21] <archivist> depends on scrounging skillz
[15:45:34] <SWPadnos> mine cost $150 or so, since I had to buy everything (no junk box at the time)
[15:45:56] <Paragon> Thanks for this info Guys...
[15:45:57] <SWPadnos> motor, enclosure, time delay relay, outlets, caps, bleed resistors, start/e-stop switches, contactor ...
[15:46:33] <SWPadnos> I probably have a schematic of what I made somewhere. if I find it I'll stick it on the web somewhere
[15:46:33] <jymm> SWPadnos: $150 ???? What store did you rip off?
[15:46:38] <SWPadnos> shhhh
[15:46:42] <SWPadnos> don't tell anyone
[15:46:48] <jymm> too late
[15:47:00] <SWPadnos> the enclosure was the most expensive part, I think that was $35
[15:47:08] <jymm> SWPadnos: *SMACK*
[15:47:14] <SWPadnos> now, off to make the coffee, for real
[15:47:38] <jymm> you can't even buy a case of corn flakes for $35
[15:48:00] <Paragon> I'm off to make space for my new toys ... CU all later and thanks again....!
[15:48:04] <jymm> Yeah, go make coffeee, wake up, and tell us the REAL cost
[15:50:15] <skunkworks> automation direct baby
[15:50:34] <jymm> skunkworks: But he said EVERYTHING for $150
[15:51:24] <archivist> hmm I have a motor from Ward Leonard speed control
[15:53:32] <skunkworks> funny. Like me and my co-worker. I round down - he rounds up.
[15:53:50] <skunkworks> my co-worker and I?
[15:54:31] <cradek> skunkworks: me is right: "Like me" + "Like my coworker" = "Like me and my coworker"
[15:54:41] <cradek> skunkworks: notice you would not say "Like I, ..."
[15:54:45] <jepler> "Like I and I's coworker"
[15:54:50] <jepler> ?
[15:55:01] <cradek> well jepler might, but he'd sound off
[15:55:18] <skunkworks> cool - thanks
[15:55:24] <jymm> I thought it usually was the other person first... My coworker and I
[15:55:41] <cradek> today's lesson brought to you by R, W, and the number 3
[15:55:52] <toastatwork> hahaha
[15:56:15] <toastatwork> ha ha ha, three endmills! ha ha ha
[15:56:19] <jymm> snuffleupagus is my hero
[15:56:30] <cradek> but HE'S INVISIBLE
[15:56:40] <cradek> what lesson does that teach our children!?
[15:56:45] <jymm> don't tell anyone
[15:56:50] <cradek> uh, "our"
[15:56:56] <archivist> Ive noted a resent change on the BBC with respect to "and I" and "and me"
[15:57:49] <jymm> cradek: they can have an imagination to retreat to when the world tosses crap at them?
[15:57:52] <cradek> archivist: a lot of people were taught incorrectly that "and I" is always correct and "and me" is always wrong.
[15:58:17] <archivist> usage changes
[15:58:22] <cradek> archivist: then they get confused and start using "myself" bogusly
[15:58:28] <archivist> same as speeeeling changes
[15:58:37] <cradek> "If you have questions, please talk to george or myself"
[15:58:47] <skunkworks> my favorite singer at the moment (feist) was on sesame street http://www.youtube.com/watch?v=9fciD_II7NI
[15:59:06] <cradek> which is "please talk to george" + "please talk to myself"...?
[15:59:29] <anonimasu> please talk to george or me is what I would say
[15:59:33] <cradek> I'm such a pedant. sorry everyone.
[15:59:48] <cradek> anonimasu: and you would be correct
[16:00:01] <anonimasu> amazing :D
[16:00:03] <jepler> Me, I'd say "ask george". I don't want to deal with those questions.
[16:00:06] <archivist> * archivist uses the Queens engrish not USAean
[16:00:07] <toastatwork> hahahahahahahaha
[16:00:11] <cradek> ok, I'm with jepler
[16:00:20] <anonimasu> our english teachers here teach a bit random of both..
[16:00:31] <anonimasu> language rape..
[16:02:11] <cradek> haha, beaker
[16:02:24] <cradek> I miss the muppet show
[16:03:42] <jepler> cradek: here, this will make you feel better: http://failblog.org/2008/11/17/sign-win/
[16:04:36] <jepler> (I don't know who started me reading failblog, but I want my time back!)
[16:04:48] <anonimasu> haha
[16:04:49] <anonimasu> laters!
[16:04:54] <cradek> jepler: I love it
[16:05:12] <toastatwork> augh i couldn't get the vim highlight to work
[16:05:12] <anonimasu> but are thoose things really staples?
[16:05:24] <archivist> I blame someone in #apache for my time on lolcats
[16:06:13] <anonimasu> http://www.morgana.co.uk/assets/Staples.jpg
[16:07:12] <skunkworks> can you use single quotes?
[16:07:29] <SWPadnos> heh, that is a funny pair of postings
[16:07:42] <SWPadnos> but the one with correct emphasis should be stapled to the bulletin board :)
[16:08:02] <anonimasu> lol
[16:10:01] <SWPadnos> geez. there it is again: http://www.newegg.com/Product/Product.aspx?Item=N82E16820145184
[16:10:21] <SWPadnos> 4GB DDR2 for $25 including shipping, after rebate
[16:10:57] <jepler> huh, why do I feel tempted to buy that?
[16:11:03] <jepler> my machines have a perfectly adequate amount of RAM
[16:11:09] <SWPadnos> because it's so inexpensive, of course
[16:11:21] <SWPadnos> adequate, is that all you got?
[16:11:39] <SWPadnos> you need LUDICROUS RAM!
[16:12:06] <jepler> it's true that my swap space is used
[16:12:25] <SWPadnos> heh
[16:13:57] <jepler> hm, but the machine in question takes DDR RAM, not DDR2
[16:14:04] <SWPadnos> oh, that's a problem
[16:14:07] <jepler> I guess that must make it ooooollllld
[16:14:13] <jepler> :-P
[16:14:36] <SWPadnos> I wonder if DDR is still available at non-usurious prices
[16:14:53] <jepler> I bought some earlier this year, but I forget the price
[16:15:09] <SWPadnos> ok, not too bad. only ~2x the price of DDR2
[16:15:16] <SWPadnos> 2G = $25 after rebate
[16:18:27] <cradek> jepler: my problem with failblog is I don't like watching people get hurt. the rest of it is really funny though.
[16:34:05] <piasdom> g'mornin all
[17:37:15] <toastatwork> i've worked my taps up to 1500 rpm and 1000 rpm
[17:37:18] <toastatwork> i wonder if i can go faster
[17:47:58] <fragalot> o.0
[17:48:44] <fragalot> one way to find out,.. but,.. don't taps have (just like drills) a certain RPM you should run them at to get the best cuts?
[17:51:11] <toastatwork> cut taps, yes
[17:51:17] <toastatwork> form taps have much higher speeds
[17:51:49] <alex_joni> I think form taps can go higher
[17:52:02] <alex_joni> but it depends on the material
[17:52:03] <toastatwork> the 1500 rpm tap is now accel limited
[17:52:12] <toastatwork> the other one has room to go
[17:52:15] <alex_joni> for reversing?
[17:52:20] <toastatwork> yeah
[17:52:44] <toastatwork> the spindle only idles for a fraction of a second before reversing
[17:52:44] <alex_joni> * alex_joni would then be happy with 1500 rpm
[17:53:03] <toastatwork> the feed rate is just shy of 40 ipm, too
[17:53:35] <alex_joni> sounds fast enough :)
[17:53:40] <fragalot> lol
[17:56:55] <toastatwork> at least it makes a cool sound
[17:57:15] <alex_joni> do visitors duck when they hear it the first time?
[17:57:33] <toastatwork> no, it's quiet
[17:57:43] <alex_joni> then it's not fast enough
[17:57:43] <toastatwork> just the fast whirr of the spindle accel
[17:57:48] <toastatwork> ahaha
[17:57:54] <toastatwork> Faster, faster, faster!
[17:58:00] <toastatwork> until the thrill of speed overcomes the fear of death.
[17:58:34] <archivist> break any taps getting it up to speed ?
[17:58:37] <toastatwork> nope, none
[17:59:18] <alex_joni> then it's definately not fast enough :D
[17:59:28] <alex_joni> toastatwork: kidding ;)
[17:59:30] <toastatwork> hahaha
[17:59:32] <toastatwork> a+
[17:59:37] <archivist> now you need spindle power measurement to detect tap wear
[17:59:52] <alex_joni> archivist: that's not that complicated
[18:00:01] <toastatwork> impossible, the accel/decel is huge compared to the running power of the tap
[18:00:14] <alex_joni> yeah, but recording the profile
[18:00:15] <archivist> servo loop err :)
[18:00:22] <alex_joni> and comparing with the next one should be ok
[18:00:36] <alex_joni> even pid profile should be somehow conclusive
[18:00:42] <archivist> wait till it changes x %
[18:05:35] <toastatwork> i guess, it's a 10 hp spindle
[18:05:50] <toastatwork> the power when it's tapping doesn't even show up in the monitor
[18:06:01] <toastatwork> the accel drives it to 50%
[18:07:17] <SWPadnos> you can gate the load checking with an "at-speed" comparison
[18:07:58] <SWPadnos> so only check spindle load once it gets up to speed (then maybe latch that status, in case the spindle slows down at all)
[18:08:21] <SWPadnos> (which it shouldn't if it's 10HP and you're tapping anything smaller than a couple of inches in diameter :) )
[18:08:40] <toastatwork> what i'm saying is the idle load is 1% or so
[18:08:50] <toastatwork> and it drifts up and down at least 1%
[18:09:00] <toastatwork> i think the error in the measurement is larger than the value i'd be looking for
[18:09:08] <SWPadnos> could be - smallish taps?
[18:09:17] <toastatwork> 10-32 and 4-40
[18:09:26] <SWPadnos> oh, tiny compared to a 10HP spindle
[18:09:45] <SWPadnos> even my 0.1HP can tap that ;)
[18:09:54] <SWPadnos> (that's my hand, not my spindle)
[18:10:08] <toastatwork> hahaha
[18:10:27] <toastatwork> it would be interesting to see if this has some method for logging tht
[18:10:29] <toastatwork> *that
[18:13:39] <archivist> may need to add a torque sensor between spindle and tap in the holder as you have a brute driving the poor little tap
[18:13:57] <toastatwork> oh, that would totally work
[18:14:14] <toastatwork> torque sensing tap holder
[18:14:40] <toastatwork> log the peak value on the holder, and once the tap line is finished, look at it
[18:14:41] <archivist> I use to work for a company making the electronics for torquemeters
[18:14:57] <toastatwork> when the toolchange goes off, cuts power to the holder and thus resets it
[18:19:15] <archivist> * archivist checks their website, looks like my old code is still being used :)
[18:23:03] <archivist> technology that was used could easily be applied to a toolholder system, hmmm I wonder
[18:32:09] <toastatwork> i cannot find any open source thing to get cnc syntax highlighting
[18:32:12] <toastatwork> what are people using
[18:34:45] <archivist> I go without highlighting at the moment
[18:37:00] <archivist> http://osdir.com/ml/gnome.general/2004-06/msg00033.html looks fixable in gedit
[18:38:26] <toastatwork> eh
[18:40:40] <archivist> I just found where to play in /use/share/gedit-2/plugins...
[18:40:48] <archivist> usr
[18:45:17] <skunkworks> I love how stuart has converstaions with himself on the email list. :)
[18:45:27] <skunkworks> trouble shooting at its best
[18:45:55] <archivist> :)
[18:50:47] <skunkworks> when will emc have double closed loop?
[18:50:51] <skunkworks> ;)
[18:50:59] <anonimasu> * anonimasu sighs
[18:51:08] <anonimasu> I've got a pysics test tomorrow
[18:51:12] <skunkworks> yeck
[18:51:39] <anonimasu> re-test actually
[18:51:39] <anonimasu> :p
[18:51:56] <anonimasu> I passed it once, but the grades sucked because I didnt have a formula collection ;)
[18:53:13] <jymm> collection?
[18:53:30] <anonimasu> the book with F=ma that you are allowed to keep on tests
[18:53:41] <anonimasu> material data and stuff
[18:53:53] <jymm> in other words.... "show your work" rap?
[18:53:55] <jymm> crap
[18:54:05] <anonimasu> what?
[18:54:28] <jymm> instead of just giving the answer, they want you to show your work
[18:54:53] <anonimasu> eah
[18:54:58] <jymm> what?
[18:55:01] <anonimasu> they grade on both the answer and the calculation
[18:55:08] <jymm> bastards!
[18:55:19] <anonimasu> but even if you fail the correct answer you can get points on the calculation alone
[18:55:28] <anonimasu> if it's 50% right or so
[18:56:00] <jymm> If you can't dazzle them with brillance, baffle them with bullshit!
[18:56:58] <anonimasu> hehe
[19:02:29] <toastatwork> i really like those kind of tests
[19:03:16] <toastatwork> at school in the ME dept, all our tests are like, single question
[19:03:25] <toastatwork> they're really cool.
[19:08:02] <jymm> Yeah, like that's a REAL tst of what you've learned or not.
[19:08:05] <jymm> test
[19:08:42] <jymm> I mena, it doens't have to be a bitch if a test, but I had a friend that graduated HS and couldn't read. - kinda pisses me off.
[19:08:59] <toastatwork> yeah
[19:09:05] <toastatwork> these were not "gotcha" questions, either
[19:09:05] <jymm> He went to college to learn to read. He shouldn't of had to do that.
[19:09:09] <toastatwork> they were simple, real engineering questions
[19:09:28] <toastatwork> "how big does this need to be? see you in an hour."
[19:09:43] <toastatwork> and that is really sad re: reading
[19:15:35] <piasdom> does emc have the ability to write script lettering ?
[19:18:07] <SWPadnos> emc doesn't know how to write at all
[19:18:12] <cradek> emc is a machine control, not a cam system. your question only makes sense for a cam system
[19:18:36] <SWPadnos> if you have a CAM program that can convert script fonts to G-code, then EMC can run that code and mill script lettering
[19:20:53] <piasdom> SWPadnos:cool...thanks
[19:21:05] <SWPadnos> hmmm. too bad this thing is so heavy: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200274154049
[19:21:13] <SWPadnos> piasdom, you're welcome
[19:21:24] <SWPadnos> (other pages show that it's in the 13000 pound range)
[19:31:27] <toastatwork> yeah, they're real heavy
[19:31:49] <toastatwork> but if it goes in a garage, the rigging isn't THAT bad
[19:32:01] <toastatwork> they essentially move it into a spot and leave
[19:32:07] <SWPadnos> yeah, I sure wouldn't want to move it up or down stairs
[19:36:36] <toastatwork> just get a couple of friends or twenty
[19:36:38] <toastatwork> it'll be fine
[19:36:50] <toastatwork> "ok guys, on three and down the stairs"
[19:40:35] <anonimasu> sweet macine :D
[20:08:09] <stustev> hat in hand - begging help :)
[20:10:00] <cradek> uh-oh
[20:12:23] <stustev> yes - again
[20:12:57] <stustev> did you see my email? I am just starting to draw it on my white board so I can understand the problem
[20:13:10] <jymm> * jymm tosses toastatwork down the stairs.... "Here CATCH!!!"
[20:13:42] <cradek> another position jump?
[20:13:46] <skunkworks> * skunkworks loves my 6'X4' white board
[20:14:00] <stustev> yes
[20:14:18] <jymm> * jymm draws on skunkworks whiteboard using a red sharpie..
[20:14:42] <stustev> whiteboards can explain a lot
[20:16:42] <cradek> hmm, I was looking at your source again, hoping there was a simple way to compile it outside emc with the ability to just run numbers through it
[20:17:01] <cradek> there's so much hal stuff that I don't see an easy way to do that - would have to replace a lot of stuff.
[20:17:59] <cradek> wow, it's getting complicated, isn't it
[20:18:37] <stustev> complicated fast
[20:20:06] <stustev> this is doing the partial differentials one step at at time
[20:20:54] <SWPadnos> you could compile it on sim and halscope some numbers
[20:21:41] <cradek> yeah
[20:22:40] <SWPadnos> one thing that struck me as odd is that the s2r function uses both p and t in calculating z, which doesn't seem right for the polar coordinate systems I know
[20:23:01] <SWPadnos> it seems to me that you'd have z=r*sin(p)
[20:23:09] <SWPadnos> but that's y in the function
[20:23:48] <SWPadnos> (actually, the order the ordinates are calculated leads me to believe that you did it "right" at first, but then swapped things around because something didn't work as you expected)
[20:26:35] <SWPadnos> stustev, what pivot_length are you using?
[20:26:51] <stustev> 5.25 inches
[20:27:56] <SWPadnos> hmmm. again, without simulating, writing, or looking at the machine, it seems strange that you have pivot_length accounted for twice in the KinematicsForward function
[20:28:13] <SWPadnos> it's used in calculating r, then it's also added directly to pos->tran.z
[20:29:25] <cradek> stustev: as an aside, I notice that you have haldata->tool_length remnants - that's a holdover from a failed previous strategy I tried
[20:32:05] <stustev> looks unused - can be removed?
[20:32:33] <cradek> yes
[20:32:46] <stustev> will do
[20:34:16] <stustev> done
[20:37:40] <stustev> looks as if I need different forward and inverse functions for the Zcomp
[20:38:20] <SWPadnos> have you tried setting various parameters (like pivot_length) to 0 to see which one(s) cause the jump?
[20:38:32] <SWPadnos> while running in sim of course :)
[20:39:48] <stustev> I have not - I don't mind using the machine - the jumps are very minor (usually)
[20:40:09] <stustev> I get no jumps until I try to use a tool_length (G43)
[20:41:29] <stustev> I think the problem is the difference between the joint[3] and pos-tran.z after the W tool length
[20:43:05] <cradek> do you get it whenever you have a nonzero W, or only when you have a tool length?
[20:43:57] <stustev> I will check - bbiam
[20:44:04] <cradek> (I bet you are right)
[20:50:12] <stustev> did g49 - g91 g28 z0 w0 - no jump
[20:50:18] <stustev> w-1.0 - jumps
[20:50:50] <alex_joni> stustev: got a link to the latest code?
[20:51:13] <stustev> www.mpm1.com:8080/cinci/cincikins.c
[20:53:28] <alex_joni> g43 sets pivot_length?
[20:54:12] <stustev> g43 sets the tool_length - I have the machine configured to use the tool length along the W axis
[20:54:12] <cradek> no
[20:54:23] <cradek> g43 is a red herring
[20:54:31] <cradek> the problem is when W is nonzero
[20:56:02] <stustev> the machine jumps when W is zero after I set the g43 h08 and move the axes to Z0 W0
[20:56:29] <cradek> yeah, I mean the unoffset W axis. that covers it up because you have an offset on W
[20:56:31] <alex_joni> yeah, but in that case joints[8] is not zero.. right?
[20:56:37] <cradek> alex_joni: exactly
[20:56:53] <cradek> well joints[8] = pos->w which are both nonzero
[20:57:08] <stustev> yes
[20:58:16] <alex_joni> how does pivot_length get set?
[20:58:48] <stustev> a parameter in my .hal file
[20:58:59] <alex_joni> so that's a nonzero constant?
[20:59:13] <stustev> yes
[20:59:45] <stustev> I will put my latest config files in www.mpm1.com:8080/cinci - bbiam
[21:00:30] <SWPadnos> somebody's gotta teach that guy about ssh ;)
[21:02:05] <jymm> SWPadnos: Ssh... it's a secret
[21:02:11] <SWPadnos> heh
[21:02:30] <jymm> a 8196 bit secret
[21:02:51] <SWPadnos> that's the key
[21:04:42] <alex_joni> stustev: is it viable to remove certain compensations?
[21:05:00] <alex_joni> it'll probably move "wrongly" .. but you should be able to spot jumps
[21:07:00] <stustev> alex_joni: can remove any and/or all
[21:07:59] <stustev> SWPadnos: I don't have ssh on the machine - I guess I should put it on there - I use it on the network but not on the machine - I will put it on there
[21:08:13] <SWPadnos> heh :)
[21:10:39] <alex_joni> stustev: for some strange reason I suspect s2r, so I'd leave only that :)
[21:11:18] <SWPadnos> yes, it does seem strange that you'd use sines and cosines the same way for both forward and inverse kins
[21:20:44] <cradek> hey, that's the part I wrote
[21:20:50] <cradek> ... well originally
[21:24:53] <SWPadnos> it seems to me that you'd need to do the (uh) forward kinematics (? - from joint space to cartesian space) sequentially
[21:25:48] <SWPadnos> take the joint closest to the tool and calculate the impact of its rotation (and W length) on XYZ
[21:26:40] <SWPadnos> then, using those results, you can apply a transform on the next joint out, which takes into account the values already calculated
[21:27:15] <SWPadnos> it's certainly possible that all this would condense down into a single equation in closed form - I haven't thought it through that far :)
[21:27:36] <SWPadnos> (either to get the equation or prove why it can't be done)
[21:31:41] <cradek> there is one pivot - from the center of A,B rotation down to the tool tip (gauge point actually). it's not a robot arm. the gauge point moves in a sphere around a point that's fixed on the Z slide. it's extremely simple kinematics
[21:33:08] <cradek> uh, "Z slide" = "joint 2 slide"
[21:33:30] <cradek> stuart is making it much less simple :-/
[21:34:54] <cradek> in his case, he has several pivot lengths that are all orthogonal - each one still gives you an offset from the center of rotation to a point on a circle or sphere found according to A,B - and I think you can just add them up to find the gauge endpoint
[21:35:33] <cradek> actually now that I come to that realization, I can see that's just what he's doing
[21:36:11] <cradek> well ... or not
[21:36:16] <cradek> I'm not sure what he's doing now
[21:39:57] <alex_joni> * alex_joni is off to bed
[21:40:02] <alex_joni> good luck spotting this :)
[21:46:06] <jepler> 'night alex_joni
[21:47:53] <fenn> dead microwave
[21:48:14] <fenn> er, whoops that whole scrollback thingy
[21:48:34] <fenn> (for your x00V capacitor)
[22:04:16] <stustev> hello again - I will try to explain what I am doing
[22:04:53] <jymm> Maybe even a LIVe microwave.... some are really cheap - some cheaper than the individual componets you steal from it.
[22:05:31] <stustev> Xcomp is to adjust Y and Z for orthogonal errors along the X movement
[22:05:45] <stustev> Ycomp, Zcomp ditto
[22:07:04] <stustev> Acomp adjusts the X axis for the out of parallel condition of the X axis and the center line of rotation of the A axis
[22:07:21] <stustev> Bcomp ditto the Acomp - just for the Y axis
[22:09:44] <stustev> the whole point is to position the tool tip in the programmed location and pose the machine to cause that tool to be in that position
[22:10:12] <stustev> the comp functions describe the physical attributes of this individual machine
[22:10:37] <stustev> this allows this machine to position the tool tip
[22:11:07] <stustev> the tool tip must be in position and orientation
[22:19:03] <stustev> cradek: stuart isn't making it much less simple he is trying to make it much more robust :)
[22:32:34] <stustev> SWPadnos: ssh is now on the cinci - so there :)
[22:32:45] <SWPadnos> ssshhhh - don't tell anyone :)
[22:33:09] <stustev> heh
[22:33:27] <stustev> too bad I can't put ssh on my white board
[22:46:44] <ds3> has anyone put together some point cloud processing stuff, preferablly within EMC?
[23:17:46] <Paragon> Hello Chaps.. Ive been looking at single to 3 ph coversion today and was wondering if someone could explain the consumption power of the idler in a rotary converter. I am awaiting delivery of a 3ph mill and Lathe. Lathe = .075hp + has suds pump 3ph. Mill = 1hp + suds + one powered table all are 3ph. I do not know the rating of the suds or table motor but they are quite small. Generaly only...
[23:17:48] <Paragon> ...one machine will be running at any one time. What size idler motor should I go for and how much power does the idler use when machines or not in use?
[23:19:08] <Paragon> ps I know did I had a discussion running earlier but this is a follow up with regards to that discussion.... Thanks
[23:23:03] <fenn> at least 1.5hp but the bigger the better
[23:23:39] <fenn> the higher the rotary converter's rating, the more efficient it will be
[23:24:20] <Paragon> fenn: Sorry I forgot to mention that the lathe motor comes with a digital inverter so it is only the mill motors and the suds motor on the lath.
[23:24:34] <fenn> oh, well, same answer then
[23:25:21] <Paragon> Oh ok :-) What about the power usage of the idler when it is not running and equipment?
[23:25:30] <fenn> also you're not supposed to keep the converter running unless you're in the shop, using stuff
[23:25:40] <fenn> like an air compressor
[23:26:27] <fenn> i have no idea how much power an unloaded motor draws
[23:26:40] <fenn> spose it would be easy enough to find out though
[23:27:23] <fenn> i've heard of "sealed rotary converters" that are filled with hydrogen for heat dissipation and lower internal air resistance
[23:28:34] <Paragon> Wow hydrogen that sounds explosivly dangerous!
[23:35:41] <fenn> nah that's a popular myth
[23:35:53] <fenn> unless you are in a submarine or something
[23:36:10] <SWPadnos> the idler takes <5% of its rated HP
[23:38:21] <Paragon> fenn: Guess you need oxygen to make hydrogen dangerous. SWPadnos is that when its supplying running equipment or when just idling with no equipment running?
[23:39:01] <SWPadnos> idling I think. it shouldn't really use much anyway - it's not driving a load
[23:39:27] <Paragon> SWPadnos: Thanks for that.
[23:39:38] <SWPadnos> I've had mine running for hours at a time, and can barely feel any temperature difference after that amount of time
[23:39:40] <SWPadnos> sure
[23:39:47] <SWPadnos> I was concerned about the same thing ;)
[23:42:53] <Paragon> Yes I read like 2.2 kw for a 3hp motor (from memory) and was concerned that it's was like having an electric fire running constantly eating up electricity ....
[23:43:14] <Paragon> Glad thats not the case :-)
[23:43:47] <SWPadnos> though it might be useful in my unheated garage
[23:44:02] <Paragon> I have been looking at this site also with regards to circuits for 3ph conversion http://home.att.net/~waterfront-woods/Articles/phaseconverter.htm
[23:45:02] <SWPadnos> yep. I think I saw that page when doing research for mine
[23:45:30] <SWPadnos> one thing to note is that if you go the VFD/static converter (or pull-start) approach, you have to derate every motor by 1/3
[23:45:56] <SWPadnos> if you build a rotary converter, you only derate the idler motor (so you'd use a 5HP motor to start 3HP loads ...)
[23:46:37] <SWPadnos> that's not even strictly required, but it's a good rule of thumb
[23:46:56] <dmess> yes... but it is noisy
[23:47:01] <Paragon> Due to receiving about 80% efficiency?
[23:47:09] <SWPadnos> what is noisy?
[23:47:31] <dmess> rotary converter
[23:47:58] <SWPadnos> not mine
[23:48:04] <dmess> cool
[23:48:30] <SWPadnos> it's worse than a desk fan bur far better than any tool
[23:48:34] <SWPadnos> s/bur/but/
[23:48:47] <dmess> the ones ive seen have been another motor running making noise..
[23:49:02] <SWPadnos> well, mine has an idler motor, but it's pretty quiet
[23:49:16] <dmess> home built??
[23:49:23] <SWPadnos> the exhaust fan on my water heater is far noisier
[23:49:26] <SWPadnos> yes
[23:50:07] <dmess> then very well done... make me a 1/2 hp one so i can run my hardinge??
[23:50:22] <SWPadnos> 1/2HP - that's nothing
[23:50:32] <SWPadnos> get a bigger motor and maybe we'll talk :)
[23:50:36] <dmess> its all it needs
[23:50:54] <dmess> but its a baby machine..
[23:51:02] <SWPadnos> heh
[23:51:05] <dmess> all it needs is love
[23:51:53] <dmess> the spindle doesnt move my .0001" indicator
[23:52:02] <SWPadnos> I more or less used the circuit here: http://www.metalwebnews.com/howto/phase-converter/phase-converter.html
[23:52:34] <SWPadnos> I changed a few things since I didn't need the remote switches, but I wanted a contactor and overloads inside
[23:52:48] <dmess> im not the strongest electonicly... im a mechanic at heart
[23:53:05] <SWPadnos> so mine has an e-stop switch, a start button, and an "overload tripped" indicator
[23:53:18] <SWPadnos> plus a few NEMA outlets (and one hard-wired feed to the bridgeport)
[23:53:49] <SWPadnos> (little extras: the start button lights up when you release E-Stop, the E-Stop button lights up when the thing is running)
[23:55:00] <Paragon> SWPadnos: I was looking at that circuit earlier today when you sent to me. How does the overload work?
[23:55:35] <SWPadnos> well, on mine I have a contactor that drives the idler (and therefore also the other loads)
[23:55:53] <SWPadnos> it's never tripped, so I don't know for sure that it's doing any good :)
[23:56:13] <SWPadnos> oh, I forgot to mention that I have a time delay relay to switch out the start caps
[23:56:23] <Paragon> A contactor? is that another name for a relay?
[23:56:25] <SWPadnos> so the contactor feeds the idler, and then there are fuses to the load
[23:56:28] <SWPadnos> yes and no
[23:56:37] <SWPadnos> contactors are designed to safely switch large loads
[23:56:48] <SWPadnos> relays are not necessarily suited for that
[23:57:00] <dmess> basically yes.. jus its really maechanical
[23:57:03] <Paragon> Oh right. i have never come across them.
[23:57:14] <SWPadnos> contactors have two contact points in series for each pole they switch, so they can't both weld closed
[23:57:38] <Paragon> Right. Like a double pole switch
[23:57:46] <SWPadnos> also, the spring is chosen so that it can break the largest theroetically possible weld you could get on the contacts
[23:58:03] <dmess> and usually strong enuf to pull themselves apart when they do
[23:58:08] <SWPadnos> additionally, there's a guarantee (by design) that all poles or no poles will switch
[23:58:38] <SWPadnos> on a normal relay, you could have a single leg weld shut, while the others open
[23:58:53] <Paragon> I see. Are these genrally available?
[23:59:00] <SWPadnos> sure
[23:59:08] <SWPadnos> search eBay for "contactor"
[23:59:12] <SWPadnos> or motor contactor
[23:59:22] <SWPadnos> or motor starter (might have overload sensing)
[23:59:55] <Paragon> http://cgi.ebay.co.uk/merlin-gerin-contactor-40amp_W0QQitemZ170279670113QQcmdZViewItemQQptZUK_BOI_Industrial_Automation_Control_ET?hash=item170279670113&_trksid=p3286.c0.m14&_trkparms=72%3A1298|66%3A2|65%3A12|39%3A2|240%3A1318