I finished installed my EQ6 belt mod kit a couple of weekends ago. New ceramic worm bearings on RA and DEC, superlube grease, belt mod installed. Checked delrin spacer sizes and replaced a couple of old worn ones (spacers).
Pros: - No grinding at all now, just sings along
- DEC axis beautifully tight compared to play it used to have
- During PEC runs Sat night the DEC trackings was unusually flat and well-behaved. Fingers crossed that's a regular occurence.
- less play in RA
- PE smoother and about 25% less
Cons: - my PE was always poor (around 30-50" peak to peak), and although things are smoother it would seem the bulk of my PE movement is in the worm/gear which the belt mod hasn't affected (it has however reduced smaller scale blips and bounces). Its still just not feasible to do long exposure images without PEC programmed on this mount, alas, which gets residual PE under +/- 7 to 10". I guess I'll have to keep saving for my EQ8 or AP mount after all
There was quite a bit of play in the bearings for my old transfer gears, so you can see things have to be better with belts if carefully installed. I tried to get decent backlash values pre-mod, but its just been too cloudy here - would be very surprised if both axes aren't a lot better in that regard.
In the meantime its been incredibly useful to understand the innards of my mount which has been on my To Do list for ages. Much more confident in how to tweak these beasts now. I'd recommend the mod for anyone contemplating an overhaul any day. The whole kit from Dave was wonderfully engineered with great instructions - a pleasure to work with.