G11 Gemini Gearboxes

[E_ri_k]

Hi all, just after a bit of guidance in my 'logic'. The other week I shifted the counterweights around a bit on my G11, not checking if they would run in to the motors! Of course it did, but not during a slew, only while tracking, so it would have just slowly approached, and then stopped I guess, and the clutch would have slipped.

However I imagine it would have still applied a fair bit of force to the whole assembly, as it sat there and slipped for about 3 hours!

I was paranoid that 'something' was damaged, so I pulled the one piece block off and re-seated it. Did some guiding and PE tests. The PE is pretty average, and whilst guiding the error will spike a fair bit and it won't guide out.

I'd een toying with the idea of the Ovision worm of the past 12 months, but never went any further with it. Ordered one last week! But back to the gearboxes. I removed the RA and DEC assembly's this afternoon, thinking I'll swap the gearboxes over, just incase I damaged the RA one. Now, the one which took the hit is a little stiff, and has a tight spot every revolution. The DEC gearbox feels quite loose, and rotates very smoothly, but also with a tight spot, but it's hardly noticeable. When I say 'loose' I don't mean there is any slop or play, it's just easy to turn.

Should the gearboxes feel tight or loose? Would it make a much of a difference as long as the worm gear is ok?

Sorry for the long post!
Erik

[JohnH]

You are going to love the performance of the G11Ovision best money I ever spent on an upgrade! No more eggy stars even at 2000mm fl.

[White Rabbit]

I had a similar issue not that long ago except my gearbox broke off. It's a very dodgy design that whole motor gearbox assembly. Basically the gear box is holding the motor on.

I removed the whole thing put it back together but the gear box wouldnt hold the the motor on straight so I cable tied the motor on to the worm block to make is sqaure. after all this I did a pe check and it brought my pe down from around 12-15 to 1.69 lol.

sounds great right, but I get large spikes as well. I spoke to Ray on the Pem Pro site and he suggests that it is purly coinsidental that I get this spike and that PE is probably not to blame. My spike appears on both RA and Dec so it must be a cable snagging on to it or something.

Is you spike in only RA?

Cheers.
Sandy

[E_ri_k]

Awesome, I can't wait for it to arrive now! Did you notice a big difference with yours? I'm really interested to see how it tracks with it.



It's shocking really isn't it. I've been trying to think of ways to modify the whole thing.....

Wow, that's interesting with your PE! All my stuff is screwed on tight, but it does flex a little with a bit of a push. I think I was getting spikes in the RA only. Would guide at +-.5 pixles, then bang! 2-3. The DEC was playing up a little also, but I walked into the mount the other night.......:roll eyes:So working on a new alignment tonight!

PemPro recons I have a PE of 12 arc secs. I do have one cable which is a bit grippy, but I'm not confined its the culprit.

Erik