I have just carefully adjusted both my DEC and RA worms using finger pressure to squash the two ends together and feeler gauges to adjust the gap between the body and the non-motor adjustment block.
Adjustment is very critical 0.002" makes the difference between getting a MOTOR STALLED message and no backlash.? I am coming to dislike the motor / gearbox / worm setup on this mount quite a bit.? I really dislike screwing the motors into the plastic gearbox plates.? They wobble and I am always scared that I'll strip the plastic thread.
My mount has steel worms which seem to work well enough but I cannot do any PE measurement right now for a number of reasons.? I fear that I may have to spring for at least one new OPW and brass worm later this year.? Along with a Gemini 2 upgrade this is getting to be an expensive mount even though I got it cheap.? Honestly, iOptron is beckoning me.
Pete