AZ-EQ6 - Worm bearing replacement

[Jonk]

I've had a good nose about, but cannot seem to find a part number for the recommended SKF ceramic bearings for replacing the standard worm bearings.

Has anyone done this to theirs, where were they purchased, and was the difference noticeable after another tune up?

I'm going to be installing a pier hopefully over the next couple of months and once the mount's installed, I don't want to remove it again unless I have to, therefore giving is the best start I can by replacing the worm bearings and another internal clean / tune up.

 

[jambouk]

Make sure you've been through this thread and message the key players to see if they have any info:

James

[Jonk]

Yes I have read and contributed to that thread the first time I stripped it down to clean / re-lubricate etc.

I now have a few pennies spare that I didn't before so want to do the bearings before it gets 'piered' outside.

[jambouk]

Ah ok, sorry.Have you asked someone like FLO if they can get the part from Synta? 

James

[Jonk]

It's not the standard ones I need, I'd like to replace the standard with ceramic bearings - lots of talk here and there about it, but no part numbers!

All I know is SKF bearings are mentioned and I don't want to strip my mount again just to get the standard part number, in order to look for the SKF equivalent.

I just hoped someone else who has done it, would have the record of what they bought.

That way I could purchase before stripping it, so I could put it back together the same day.

[Skipper Billy]

Why ceramic bearings ??  I use them in the miniature gas turbine engines in my model aircraft because they will stand temperatures of circa 1000º C and are happy with the 180000 rpm - two conditions that shouldn't exist in a  telescope mount!!

I swapped the bearings in my HEQ5 for SKF/FAG standard steel bearings and the improvement over the original bearings was like night and day - so much smoother, quieter and accurate but I really cant see the benefit of ceramics - a possible downside is they have more free play in them than standard steel bearings at room temperature - something we really dont want in a  telescope mount.

Also if you get the adjustments too tight they will break - ceramic bearings are very fragile.

 

 

 

 

Edited April 22, 2016 by Skipper Billy

[Jonk]

I don't know the reason people use them, but they appear to be highly recommended by others.

[Jonk]

An older thread, but I've started looking into this again and still can't find the info I need.

Does anyone have a list of part numbers / supplier for the SKF bearings required for the AZ-EQ6?

[mikeobrien]

Worm gear bearings are SKF608 2RSH or you can use SKF 608 2Z which has metal dust covers, If you are in the UK you can order these from Simply Bearings.

 Simply Bearings Ltd
Halton House
Greenfold Way
Leigh
Greater Manchester
WN7 3XJ

01942 269837

[Jonk]

Thanks Mike, I'll take a look.

[oymd]

On 15/08/2018 at 14:11, mikeobrien said:

Worm gear bearings are SKF608 2RSH or you can use SKF 608 2Z which has metal dust covers, If you are in the UK you can order these from Simply Bearings.

 Simply Bearings Ltd
Halton House
Greenfold Way
Leigh
Greater Manchester
WN7 3XJ

01942 269837

 

On 15/08/2018 at 22:43, Jonk said:

Thanks Mike, I'll take a look.

 Very sorry to resurrect this thread. 
 

I need to replace the bearings on my RA worm shaft of the AZ-EQ6 Pro

Are these the ones described above?

 

[Jonny_H]

Yes I believe the bearings are the same as mentioned in the previous post above. FYI I purchased mine from Acorn Industrial (part numbers below) for my AZ EQ6 GT.

ACORN CODE	608-2Z-SKF
HS CODE	8482 10 90 30
COO	IT

[oymd]

1 hour ago, Jonny_H said:

Yes I believe the bearings are the same as mentioned in the previous post above. FYI I purchased mine from Acorn Industrial (part numbers below) for my AZ EQ6 GT.

ACORN CODE	608-2Z-SKF
HS CODE	8482 10 90 30
COO	IT

Many thanks for your reply.

Is it this one?

https://www.acorn-ind.co.uk/p/skf/single-row-deep-groove-ball-bearings/608-2z/c2egjn-skf/

 

The inner diameter is 8mm and outer diameter is 22mm

The outer diameter fits with my measurements, but the inner diameter is 8mm?

I measured the shaft at 14mm?

Does the shaft narrow down to 8mm inside the bearing?

Many thanks

 

[Jonny_H]

Yes, on mine the shaft narrows down to 8mm where it passes through the bearing. I assume yours will be the same.

[oymd]

1 hour ago, Jonny_H said:

Yes, on mine the shaft narrows down to 8mm where it passes through the bearing. I assume yours will be the same.

Perfect. I’ll order two bearings. 
 

Can you please advise how to actually remove the shaft and bearings?

 

[oymd]

The mount is currently abroad. 
 

The only model I can find in the local market is:

SKF 608-ZZ

Is that similar to the 608-2Z?

There also seems to be a SECONDARY encoder housing on the shaft, so it seems the worm shaft cannot be removed while the mount is assembled. It seems that I need to strip the mount again and access the RA carrier and housing from inside. 
 

 

Edited February 11, 2022 by oymd

[oymd]

I thought I would update this thread with my findings, just in case someone else needs replacing the bearings on their AZ-Eq6 Pro mount. 
 

Thr bearings used by Skywatcher are: 

JESA W5 608Z

22mm diameter 

8mm bore hole

7mm thick

”Z” seems to stand for SEALED bearings with the metal plate. 
 

I could not find any SKF bearings in the local market, and I used Japanese NSK bearings. 
 

They did the job. 
 

For reference the bearings needed are:

SKF 608-2Z ( think the 608-ZZ is the same)

or

NSK 608 Z

Also, just a work of caution. The worm shaft CANNOT be pulled out of the RA worm carrier with the mount assembled. There is a plastic plate on the shaft that is sandwiched by a sensor which makes up the secondary encoder. 
 

A full disassembly of the mount is required.  

Edited February 15, 2022 by oymd

[Same old newbie alert]

Looks the same sort of setup as most of the other synta mounts in the weight class, the size of the bearings is the same on the cgem.. you will need possibly a couple of tools and hope it's not glued in with loctite

On reassembly that threaded washer needs to be tight enough not to lock up the bearing but not too loose to have any lateral movement in the worm spindle..

Edited February 15, 2022 by Same old newbie alert
Added info