Re: [CAD_CAM_EDM_DRO] Re: Lost steps

In a message dated 8/20/00 3:42:09 PM Central Daylight Time, Ozzie@...
writes:

<< During an hour's
no load testing the motor gets quite warm, maybe 100 degrees. >>
Now, that, alone, sounds like you have the driver set wrong, if it's a
"pulse-width chopper" type, or, the wrong "ballast resistors", of one of the
old "unipolar" kind.

The "step skipping" sounds like electrical noise, and though you have taken
SOME steps with the foil, etc., you may not have the CIRCUITS properly
by-passed!

It is also POSSIBLE that you have bad bearings. I had a relatively-new
Superior (NOT!) Electric motor "do that" on me, years back, and I disovered
the "front bearing" did NOT have a SEALED, perm.-lubricated "DCC" bearing,
but only a SHIELD! That is, dust could "get it" along the shaft, as the
end-bell's hole was a good 0.05" larger dia., of course, and the "front
bearing" was pressed in to that bell, so it was a "clear shot" from the
outside-world to the bearing's ball-races! DUM! I hadda keep the machine
going, so I spent the $200 to replace the "bad" motor, only to discover,
later, it was only the bearing causing the hassle! So, I cobbled a clever
neoprene/grease-filled seal which did the trick, and then went about
replacing the offending bearing. Took some care, as dismantling a stepper is
a "no-no"! Done, and it's "perfect" again! Just because catalog lies!
(Sealed bearings, lubed for the life of the motor.") What can one do???