I disconnected the 3 signals from the spindle encoder leaving the ground 
and 5 volts in place. To my great surprise, turning a tooth still 
crashed it. Getting out my looking glass, I came to the conclusion I had 
a boatload of hair sticking out of most of the solder joints, raising 
the chances of something actually contacting something it wasn't 
supposed to.  Clipped it off, crashed the pi while remounting the 
encoder.

Humm, since the index is mounted opposite end active, and the 5 volts to 
that ATS667 had to go thru a sot I had milled in the wall of its 
mounting pocket, the solder joint stuck up enough to contact the bull 
gear tooth on its way by, which was shorting the 5 volts for a fraction 
of a second as it went by. Looking in various places I noted that the 
endoder has a quadrature error output pin but that it has to be enabled 
before is has any output.

Peter: can it be setp'd true without screwing up its other functions?

So thats tomorrow, and I am hoping that the sign of the average will tell 
Peter which way I need to move the A chip to reduce the error.

Its likely to be a very noisy output as the variability can easily be 
seen in the halscope. TBT, this bull gear has been nearly destroyed by 
80 years of having tons of overpressure when the backgear is engaged, 
and its so common a condition its obvious the guy in charge of adjusting 
that during final assembly had never been instructed on how to do it 
properly.

Anyone else with a Sheldon should put it in backgear and listen.

If you are hearing or feeling a rumble, lift the lever toward 
disengagement and listen for the rumble to go away, and the remaining 
noise is much quieter and reminds you of a bell. Loosen the handle and 
adjust the eccentric until it sounds like that when fully engaged. The 
other dead giveaway is if any of the tooths flat tips are worn smooth. 
If that condition exists, the teeth on the smaller of the 2 mating gears 
are being pinched and bent at the root of the tooth and will eventually 
break off from metal fatigue.

I got lucky and have not busted a tooth yet, but several people on the 
Sheldon list have not been so lucky.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page <http://geneslinuxbox.net:6309/gene>


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