On Wednesday 18 December 2013 01:16:47 John Alexander Stewart did opine: > Hi Gene - by: > > John: You need finer grained control than an index generator will ever > > > allow if you ever intend to use the G33.1 or G76 thread cutting on the > > lathe, and once I had that working, I don't know why I ever considered > > not doing it. > > I presume you mean the one pulse per rev that Mach users seem to be > stuck with.
Yes, poor things. > Code for encoder wheel came through, by the way. I did measure the > spindle diameter (not by lathe right now) so can not comment on how > well it'll fit with your GCode. > > The Emco (Austrian, Enco is Asian) will be running with a 3 phase motor > and inverter - already here, just waiting to be installed. The inverter > takes 0-10v for the spindle - so that's good. Whereas I took the cheap way out and bought a 1.5hp treadmill motor off fleabay, controller and all < $100 bill. But 2 things wrong with the controller, starting with its being an scr model so it hummed to beat the band at medium speeds, plus I blew two of the darned things with accidental shorts while first assembling it. In the end I wound up buying a hexfet based controller, 25 amp rated from Empire in Wisconsin, around $150, runs dead silent and has almost 300% the capacity this motor needs. Then because the motor is bigger, it of course wouldn't fit in the pocket under the bed where the 200 watter was. So I made a jackshaft assembly that sat in the old motors position, using a new but same teeth timing pulley in the same location as the OEM motor would have held it, but used a 3" poly-groove pulley on the other end that the 1" pulley on the new motor drove, so I had a 3/1 step down to the original backgear equipt head. The tread mill motor can easily muster up 10+ grand at about 9.5 volts into the controller, so I am presently setup for about 2k max revs at the spindle nose, with enough torque to turn the house around. Max volts from the pwm converter is about 8 volts so even at that speed, the servo speed control is very strong. Where before I was out of torque pulling a 3 thou by 2 thou chip off a piece of 3/4" cold roll in a 4" chuck it now has a much better built 5" 4 jaw, and I can now pull a 10x10 chip off of a 2" diameter piece of steel. At speeds that have the inserts edge itself dull red. The other half of that is the strength of the gears in the head, particularly the hub keyways, so I expect to be looking for better gears if I make a habit of that big a cut too often. :( By the time I was done, with a suitable suicide braking setup to be able to run the g33.1 in peck cycle, I expect I have the cost of your 3 phase motor and its inverter in it. And my .hal file is over 1200 lines! The hand made box on the rear of the lathe to contain all that just kept growing, but its not in the way so its a shrug, it keeps the swarf out of the electrics. That motor is very quiet, all you can hear at 10k shaft revs is the air from the fan cast as part of the pulley. The Z stepper setup is far noisier as it has the clearances of a 2/1 spur gear stepdown to drive the 16x5mm ball screw. Thats a major clatter maker as both gears are from a metal gear change gear kit. Someday I'll put a much quieter timing belt setup on it, but the gears are what I had on hand, just needed bore machining for some home made taperlock hubs. > This is all interesting! Thank you - John A. Stewart > ------------------------------------------------------------------------ > ------ Rapidly troubleshoot problems before they affect your business. > Most IT organizations don't have a clear picture of how application > performance affects their revenue. With AppDynamics, you get 100% > visibility into your Java,.NET, & PHP application. Start your 15-day > FREE TRIAL of AppDynamics Pro! > http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.cl > ktrk _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> Tact is the art of making a point without making an enemy. A pen in the hand of this president is far more dangerous than 200 million guns in the hands of law-abiding citizens. ------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
