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Ramsay11
01-07-2011, 12:46 AM
I submitted a thread June 6 about the issue and received helpful advice but my problem persists. I contacted Hollywood General Machining, they suspected the Digital Drive Controller and offered to replace but I don't believe it is the problem.

Just to recap - mount at times will not move in RA, especially notice when using hand controller to slowly slew and hone in on object. This will happen an hour or so later, when temperatures drop and I suspect battery is at fault - yet the battery is fine and the DEC movement via hand controller is fine.

Swapping leads on Digital Drive doesn't reveal the issue is a faulty output to the RA Motor,

RA Oldham coupler is snug, motor moves, worm moves and appears to be well meshed into worm gear but worm gear doesn't always move the mount in RA. Have reset the worm alignment and verified as recommended.

I do notice if scope is in certain positions, (parallel to RA, significantly east or west of RA axis) the RA drive will perform differently, sometimes not moving at all. The mount is levelled, well balanced and well within load recommendations.

Tightening the RA clutch doesn't have as much impact on the RA resistance to movement as the same occurs when the DEC clutch is tightened.

Is there a possibility I am missing a washer or pressure ring in the RA assembly? Does anyone have an exploded parts diagram for me to verify. I have contacted the manufacturer about this and received no reply.

Stephen

Visionoz
01-07-2011, 01:47 AM
Stephen

Have you checked the clutch yet? Seems to me like it is slipping - there must be no grease/oil whatsoever on the clutch; perhaps some ingress of grease/oil has occurred and is causing this problem

If you loosen the large end RA lock nut - the one that you loosen/tighten to suit - you can remove the whole RA axis and see the large nylon clutch disc

I own a G11 however it should work the same for the GM8

Anyway some others with more accurate information might chime in

HTH
Cheers
Bill

[1ponders]
01-07-2011, 07:11 AM
Hi Stephen.

When you say you swapped the leads over did you swap the entire leads or just swap the motor ends?