Re: [CAD_CAM_EDM_DRO] Re: Stepper Dissasembly

Chris:

Don't get me wrong, I have spoken personally with Mariss before and he
IS a knowledgeable guy, but I work every day with nuclear physicist's,
radiologists, cardiologists, etc. and NEVER confuse a knowledgable guy with
someone who is always right. The only real advice you can trust is your own.
In terms of taking apart a stepper motor, it can frequently be done, does it
sometimes lower its torque or even destroy it? yes, but most of the time it
doesn't. Its like static. An engineer will tell you that you must NEVER
touch a pc board without ground straps, those of us who work on multi
million dollar systems, almost never use them ourselves because we learn
from experience, that nothing bad ever seems to happen from not doing so.
Experts tell us, never take apart many of the modules we work on, but I
frequently do so, saving 10's of thousands of dollars in the process. There
are no absolutes, I willing to bet that Mariss has found that some of the
steppers he's seen taken apart never work again. But how many has HE taken
apart. Urban myth is created by putting too much faith in what others claim.
I certainly wouldn't throw out a stepper motor because someone says it won't
work to create a new back plate, chances may be 60% it won't work, but that
still leaves 40% that it will, and to a hobbiest, that 40% is good enough.
This isn't a flame, just pointing out that sometimes, good enough is
good enough. Tell an audiophile that the 1" thick speaker cables aren't
doing him any good, and he'll line up 30 experts to tell you all about skin
effect, power peaks, current limitation, etc...but sit him in front of two
stereo's, one with 1" thick wire and one with 20 gauge, and he can't tell
them apart. Remember, engineers don't have time to test all the theories
they learn, but sometimes they need to be tested. I always try to, and I win
a significant portion of the time.

As to your steppers, I've had the rotors out of mine several times, they
still reassemble, work great, and I didn't have to rewire. I just cut the
ends of the coils , wired them in series, and hooked them up. Ive never
blown a controller (Can't see why I would, it just chop's at a different
frequency if it needs to) and I don't really worry about inductance,
capacitance, etc. I just adjust voltage and current till they work good. If
their too slow or not powerfull enough, you can always try again with
different windings. I really think this line about not taking apart a
stepper is an urban myth, told only by people that have never taken them
apart.

Remember the smoke though. :)
Art