rocketscientistnate wrote:
There doesn't appear to be that much gummy stuff, and most of it is at the end. When the machine is off, I can turn the motor and move the quill quite easily by turning the position indicator (about 1.5" diameter) mounted on the end of the motor shaft. It moves smoothly and easily all the way up and down. Should the stickiness be something I should be able to feel when doing this?
Yes, if it is binding, then you would be able to feel it.
It won't hurt it to give it a good cleaning and it sounds like the cheapest potential solution. Also are you saying that all motors for this need about 2500 oz-in of torque? Or that servos need 3 times as much as steppers? I think I had read about 900 oz-in for a stepper replacement works good on these.
No, 2500 Oz-In would break things. Usually, because steppers lose so much of
their (holding) torque when moving, a servo with a much lower rating can be
used. I'm using a motor with about 150 Oz-In torque on my Bridgeport quill.
This isn't a BOSS quill, but a manual head with an external ballscrew added to
the front. The Bridgeport power feed has an overload clutch that is to be set
at 200 Lbs. linear force, so you don't want more than that, anyway.
So, I'm suspecting there is some other problem that is causing lost steps.
Could a pulley be loose and slipping? I've sure seen this before.
Make sure the lube system is getting to the quill ballscrew, the lines or metering
orifices can clog up.
Jon
