Hi Greg,
A couple of thoughts on your process. You are not likely to get very low tracking error numbers with the stainless steel worms, you must have brass worms for the best precision and tracking. You must have some worm gear backlash between the worm gear and the worm wheel on RA, DEC is often times better with a bit less but in any case you cannot just set the backlash in the heat of the day and expect the backlash to remain the same. As the air temps drop so will the worm gear clearance, set your worm gear backlash in the COLD.?
Also none of the felt backlash can come from movement of the worm gear on the worm gear axis, it MUST have s slight preload, there can be no freedom between the gearbox output and worm gear input shaft, the coupler must be tight and free of any play. Check your worm gears for end play, it should be zero or darned near it, if not adjust it by compressing the worm gear bearing mounts inward while setting worm gear mesh. This is very difficult and the reason the Losmandy OPWs were designed.?
You may just have a less than ideal worm on the RA, swap it with the DEC worm and retest. It may be that your DEC worm is better. Nobody cares how well your DEC error is, if you have a good polar alignment the DEC axis should not move at all. Swap the worm gears and retest, this may solve the basic issue, the rest is just adjustment.?
I hope this helps! Happy Thanksgiving!
Chip
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