On Thursday, May 31, 2012 11:28:24 AM John Thornton did opine: > I'm sure fresh bearings would help the 15hp and it is a heavy duty TEFC > motor. I might pull it apart today and order some new ones... > > I didn't measure the temperature of the 10hp and only ran a few minutes > but I'll keep an eye on it. > > I didn't ask for taps on the transformer but it won't hurt to find out > the price. Input taps for 220 and 240?
Since the existing autoformer has taps for 208, 220 and 240, I'd say an extra at 220, so you could use it for a 220 to 240 step up, or conversely swap primary & secondary & use it for a 240 to 220 step down would cover the options nicely when combined with the autoformers own taps. The N terminal on the existing autoformer can then be taken back to neutral in the service, thereby forcing the secondary side to become neutral referenced. If this tranny comes with N connections on both windings, the N connection on whatever winding is used for drive to the existing autoformer could also be tied to this neutral run, but that would be more for correctness than any real advantage since it's the N terminal of the OEM autoformer that counts here. I'd check my copy of the NEC, but it's either grown legs or belonged to the tv station. In any event its a '98 issue and could be obsolete. I haven't stumbled over it in 3 or 4 years. > How is the encoder disk coming along? > > John > > On 5/31/2012 7:21 AM, gene heskett wrote: So-so. I, took that printout out there yesterday, but being somewhat fam with the old code, and having a supply of #58 & #60 pcb drills, I massaged that code for the smaller bits and tried to make a 60 slot encoder, then, trying to get the exec time down (its about 2.75 hours with that small a bit) I pushed too hard & broke the last #58, so I slowed down a bit more. So I've broken about $35 worth of bits now to get one poorly cut disk. I added a duty cycle fudge value where the original code just divided by 2.0. Since mulls are faster, the disk I made yesterday now has a mull by duty_cycle, with duty cycle at .45. Next one will be at .40 to equalize the opto outputs to 50%, they were about 57/43 when I put it on the lathe. I have the A/B slot ring about correct if I reduce the duty cycle from .45 to .40, I should get pretty close to a 50% duty cycle out of the opto devices. I can bend them back and forth perhaps 10 thou to fine tune the quadrature timing, or adjust the slot count one way or the other by one count. But I think I am going to have to dig another 5 thou deeper into the piece of oil soaked oak used for sacrificial in order to remove the last vestiges of the fact that its not an end mill, but a drill bit with fairly steep angles. It left a fin at the bottom of the slot. Going from 39 to 60 slots, I had to adjust the encoder's scale & negate it but that was half expected. And I have too much gain, the speed is hunting about 10%. Then, I am going to have to separate the slot cutting and inner hole cutout from each other in the codes looping so this thinner stuff has less opportunity to flex, and after fighting with the index slot, trying to maintain its tapered shape, it occurred to me that a simple slot perhaps a thou wider than the bit itself is all that needs since I don't think it needs a specific timeing reference the A/B slot ring. So that is the next change for this code. The .001 off line movement there is about the limit of my mill, but would be intended to assure that only one edge of the drill is doing the cutting. When both edges cut, the cut isn't as clean as the bit flexes. I ordered another 5 pack of each bit size yesterday. $89. Another thing that I question is the math that does the tapering of the slots, I have a feeling its not quite right, but cannot put my finger on it. That is about a screen full of code in vim all by itself just to make the 5 moves that carve the slot at each depth increment, and the last movement should be to the origin of the end of the first movement, but there is a small gap when you zoom in the backplot to look at slot 0 and the index or to any individual slot. The error is at least consistent though so should be fixable. I haven't started on that yet for today, I need to make a trip out to get some blood pressure & anti-sugar pills & some groceries first. And since the temps are decent, I need to fire up the weed eater & finish trimming my jungle too. And when I do get to the shop, from the looks of things in the mills head, I need to replace one of those plastic gears, a hub is starting to break out and the gear rim is flopping up & down about 1/16" with attendant rattling noises. There was, 10 years ago, a belt drive kit for this thing that gave a max rpm of 5000 but that was discoed several years ago. Damnit... If they ever get my nose cleaned up for good, I'd like to get a G0704 & a ball screw kit for it, it would *2 my xy envelope. Z I have lots of thanks to the all new Z drive I built several years ago. That old saw about wishes, horses and beggars comes to mind. Dreaming is of course free. :) Thanks John. 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) My web page: <http://coyoteden.dyndns-free.com:85/gene> Most people want either less corruption or more of a chance to participate in it. ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. 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