George,
The grinding was probably the cheap or damaged bearings they use in the Chinese mounts. I had a new Sirius HEQ5-PRO that had been assembled with the RA tapered bearings so tight that the cheap Chinese bearing seats were permanently damaged. I had to use a strap wrench to loosen the retainer. I replaced all of the larger tapered rollers on RA and DEC with SKFs and the mount was fantastically smooth. I had used Bellevue discs and precision ABEC7 bearings for the worms and Timken deep groove bearings elsewhere for the worm wheels. Huge improvements in movement and PE. The belt drive was a big help to, I loved doing the EQMOD stuff but the Atlas had no chance to carry the payloads I wanted for imaging so before I went down the road I did with my 2x Sirius mounts I dumped them all and bought a used G11.??
--
Chip Louie - Chief Daydreamer Imagination Hardware
Chip Louie