C8 RA Knob has play.......
Posted 04 April 2005 - 02:31 PM
I have a Classic Orange C8 I got about a month ago. There were a few stars out last night (1st time in 3 weeks!) and I decided to do a star collimation test (passed ). I noticed that the RA adjustment knob has somewhere between a 1/4 and 1/2 turn "slop" or "play" to it.
Is this normal?
Can it be adjusted??
Posted 04 April 2005 - 03:11 PM
Posted 04 April 2005 - 04:16 PM
Posted 05 April 2005 - 12:24 AM
The R.A. knob on the older C-8s is connected to a shaft containing a small pinion gear. The pinion drives a larger gear that moves the scope in R.A when you turn the knob.
If you can truly turn the knob 1/2 turn before it engages, and you're sure the set screw on the knob is properly tightened, it's possible that the pinion is loose on the shaft.
But, checking requires a major tear down. So, before doing anything, be sure the clutch itself is also properly adjusted. I don't believe there is a way to actually adjust the mesh of spur and pinion gears, but if the pinion is loose, you could probably super-glue it. Actually, my best advice is to take a look at a similar scope owned by a buddy. That will give you a reference point.
Keep in mind that there is some play in all these type C-8s RA knobs.
Posted 10 April 2005 - 01:29 PM
Embarassed but relieved :o