HEQ5 pro worm drive bearings

[Owmuchonomy]

So following on from my thread regarding the 90 second sudden 'heartbeat' on the PHD trace in right ascension on my mount I stripped the RA axis down. This is the third time I've had this mount apart so it's getting much easier and faster to do. When I got to the worm drive shaft I noted that one of the two bearings, the one on the drive end, was not running smoothly and had quite a notchy feel to it.

So I ordered two new ones from Simply Bearings for about £5 at 3pm on Friday. They came the following morning (wow, impressed) and I fitted them.

I rebuilt the mount. I did note that the RA worm drive fine adjustment was much easier this time around. I tried the mount guiding last night and I must say it's the smoothest PHD graph I've ever seen for my gear. So no sudden arrythmia at all.

Photos of the bearing reference for anyone who needs it is above.

[wxsatuser]

Just taken mine apart.

Quite impressed as it looked very good inside but two of the main ball bearings on each axis are a bit rough.

Got all new bearings coming next week.

[Owmuchonomy]

Just taken mine apart.

Quite impressed as it looked very good inside but two of the main ball bearings on each axis are a bit rough.

Got all new bearings coming next week.

Great. Hope it helps your mount. I also got rid of the black molasses that SW coated the shaft in and used some Molybdenum grease instead.

[kalasinman]

Nice work! I just had my mount down and found a rough RA worm bearing due to excess preload. Factory is sending out new ones. I wonder what grade of bearings are used in these devices as precision is so critical. ANSI/ABMA standards grade bearing balls from 3000 to 3 with the smaler number being the higher grade. Good bearings are harder and more precise. I'm curious as to whether installing high grade bearings would improve mount performance.

A bearing of grade 10 is the lowest level of high grade and is round to .00001" while a grade 3 is round to .000003. Surface roughness of a grade 3 is half that of a grade 10.

Bearings are usually standard items available by number from bearing suppliers. Just a thought...--Jack