Thread: MX RA Backlash!
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Old 29-10-2013, 01:08 PM
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PRejto (Peter)
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Quote:
Originally Posted by rally View Post
Peter,

If you physically apply varying pressures to your RA axis in both directions, Do you get physical movement showing up at the camera ?


You would expect to get some movement, the issue is if its actually backlash

Rally
OK, I put the scope/mount to ca +15 DEC/meridian and applied some pressure back and forth to the counter weight shaft. In that position the counter weight shaft is horizontal. The RA axis moves and the camera swings quite a bit relative the ground. Pushing on the end of the scope in the declination direction produces close to zero motion. So, there is quite a big difference between the two axis.

I removed the cover of the RA axis. I would expect to see movement in that situation since the cover locks the worm down in tracking mode. I applied upward pressure to the worm gear housing which I think engages the worm and the ring gear. It takes a very large amount of pressure to diminish obvious movement of the worm gear assembly. I don't have any idea if this test is valid to determine anything.

I guess the RA movement might be indicative of something since it seems so much more than the dec axis, however there is also a lot more weight moment on the RA axis. Perhaps that is responsible for the movement. I'm not sure.

Peter
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