AZ-EQ6 RA bearings, what model?

[ONIKKINEN]

Anyone know which bearings are these in the RA axis of the AZ-EQ6?

I dismantled my mount to see why the RA axis is maybe a bit unnecessarily difficult to balance and doesn't seem to be fluid. The mount is not broken or anything, it works just fine but i would like to see if it can be made better. The bearings seem rather crude and definitely not good quality bearings but likely some cheap low grade stuff that really shouldn't be put into mechanical things that need precision and fluidity. The lubricant is also a bit more in the sticky rather than fluid side than it should be.

So, anyone know which model of bearing to look for to replace these?

[david_taurus83]

https://stargazerslounge.com/topic/384486-pier-time-today/?do=findComment&comment=4246975

 

What good timing! Literally just done it. I done all the thrust bearings and worm bearings. Those needle rollers in the casting, I didn't do those as they are not easily removed. I considered it but with the cost of a blind bearing puller which I don't have, and around £25 for each one (NK40/20TN SKF) I didn't think it was a cost effective upgrade as they won't offer any performance increase. You would need to destroy the bearing as well to remove it. Both axis turn on the thrust bearings so they are the ones to improve.

[ONIKKINEN]

Exactly what i was looking for, thanks a bunch! Didn't spot your thread by searching for some reason.

6 minutes ago, david_taurus83 said:

 Those needle rollers in the casting, I didn't do those as they are not easily removed.

I will see if i can easily remove them, if not then ill leave them be as they are just supporting bearings. I used to do mechanic stuff for cars and most bearings like this (in engines mostly) do not come out cleanly unless they are well worn. But sometimes slightly heating the casing with a hot air gun and hitting the bearing from the inside with a piece of wood of the right size and they fly off. With a piece of wood you dont actually damage the bearing after a few hits so the option to leave it be is still there even though its less likely to work than something less agricultural.

[david_taurus83]

5 minutes ago, ONIKKINEN said:

Exactly what i was looking for, thanks a bunch! Didn't spot your thread by searching for some reason.

I will see if i can easily remove them, if not then ill leave them be as they are just supporting bearings. I used to do mechanic stuff for cars and most bearings like this (in engines mostly) do not come out cleanly unless they are well worn. But sometimes slightly heating the casing with a hot air gun and hitting the bearing from the inside with a piece of wood of the right size and they fly off. With a piece of wood you dont actually damage the bearing after a few hits so the option to leave it be is still there even though its less likely to work than something less agricultural.

Have a look through the mount. The outer race is obscured by the mount casting so you'd probably just smash through the nylon cage! On 3 of mine, there maybe just, and I mean just enough of the outer race available on the inside to 'grab' with the flange on a blind bearing puller (those hammer type ones). If I was really determined I'd probably just pry the nylon cage out and the pins with a screwdriver and remove the outer race on its own. You destroy the bearings this way but you are replacing them anyway. Of course, you probably have fsr more experience than me at this sort of thing anyway!

[ONIKKINEN]

On 28/05/2022 at 22:36, david_taurus83 said:

Have a look through the mount. The outer race is obscured by the mount casting so you'd probably just smash through the nylon cage! On 3 of mine, there maybe just, and I mean just enough of the outer race available on the inside to 'grab' with the flange on a blind bearing puller (those hammer type ones). If I was really determined I'd probably just pry the nylon cage out and the pins with a screwdriver and remove the outer race on its own. You destroy the bearings this way but you are replacing them anyway. Of course, you probably have fsr more experience than me at this sort of thing anyway!

I see what you mean, there is almost no metal edge to strike on for the bearings in the cage. I dont see a way to take them out without smashing them to pieces and also probably damaging the casing so better to leave them in place since they are not really in need of changing right now anyway.

On another note i found some real gremlins inside the mount like pre stripped philips head screws so i dont have to strip them myself. How kind of Skywatcher to do it for me 🤣. Also found that the cage bearings were underlubricated while the roller bearings were grossly overlubricated in the DEC axis while OK in the RA. Seems like someone assembling these puts more or less a random amount of grease in the bearings... Some rough to the touch surfaces too but these are under the roller bearing steel washers so shouldn't cause friction but better to clean it out properly anyway. Disappointing workmanship at display but the mount is quite cheap so i guess its a given.

I will be surprised if performance doesn't improve after this (provided i dont fumble anything).

[david_taurus83]

Best thing I've done with it so far. Guiding has been great. I used to always get messages saying dithering settle timeout. Everything just works properly now.

 

[ONIKKINEN]

33 minutes ago, david_taurus83 said:

Best thing I've done with it so far. Guiding has been great. I used to always get messages saying dithering settle timeout. Everything just works properly now.

 

That does look good, almost too good 🤣.

Mine looks like this, although so far i have not had the pleasure of using the mount in completely windless conditions so there are some little temper tantrums here and there and its a bit difficult to tell what is guiding related and what is external, but at least from the calibration result its easy to see that there are some mechanical issues since the impulses are bunched up in pairs.