Qhy filter wheel question

[assouptro]

Hi Starpeople! 
I have bought a second hand qhy filter wheel that has an issue 

It is the QHYCFW3L-SR 7 position 2” filter wheel 

I knew there was an issue with this filter wheel, a problem that is caused by the centre screw on the back that you aren’t supposed to adjust

 

This screw tightens or loosens when the wheel turns resulting in the wheel locking up or becoming so loose the wheel wobbles and catches against the case 

I have contacted qhy and been told to use thread lock 

I just want to know if this screw normally turns with the wheel or if it’s static? 
If anyone here with a qhy wheel has noticed this I would really appreciate the information 

Many thanks 

Bryan 

[skybadger]

I have a qhy2 wheel. The screw is meant to be firm but not super tight as there is a thrust bearing In the inside to enable rotation. Of course the qhy3 fw may be different again. 

[assouptro]

18 hours ago, skybadger said:

I have a qhy2 wheel. The screw is meant to be firm but not super tight as there is a thrust bearing In the inside to enable rotation. Of course the qhy3 fw may be different again. 

Thanks for your help Badger!

have you ever dismantled the central “spigot” to reveal the bearings etc? 
 

Cheers 

Bryan 

[scotty38]

The screw does not move on my CFW3

[skybadger]

47 minutes ago, assouptro said:

Thanks for your help Badger!

have you ever dismantled the central “spigot” to reveal the bearings etc? 
 

Cheers 

Bryan 

Sure have - I was having issues with the filter wheel returning to the same location.  SO I took the lot apart to see if I could find the problem. Its not a bearing as such, more a bearing groove with lots of separate balls. Re-assembled and moved on. 

In the end the problem was the power supply was not reliably giving 12v rather than an issue with the filter wheel itself.  Now works fine. 

 

[scotty38]

There is a FW update, for the CFW3 at least, that gives unidirectional rotation which helps with filters ending up in the same position.