Avx problem

[Maclean156]

Hi...last night I discovered a problem with my avx mount. With the clutch engaged on the declination I have about a couple of mm free movement when I check clutch. On hand control I get immediate movement of the declination but there is this slight free play. For example if I stop slewing and hold the counter weight bar I can easily make the scope move a little each way. 

What's happening? 

[PeterCPC]

I'm not sure that I understand exactly what you are saying but are the clutches fully engaged? If not you can take the knobs off and move them back and reattach. I did this and I also use a piece of 1/2" copper pipe to put over the end of the knobs to give a little bit more leverage.

Edited October 9, 2021 by PeterCPC

[Maclean156]

Declination clutch fully engaged and tight. I have slight left and right movement until resistance is felt. No pressure needed to make this movement happen. Can see the top alignment mark moving slightly back and forth just by a couple of mm just by pushing either side of scope with the tiniest of pressure. 

So annoying as don't really want to send scope back as other half threw out all the boxes lol

[PeterCPC]

Have you tried removing the Dec clutch bolt and cleaning the end of it?

[Maclean156]

Ok will try that. 

[Maclean156]

Done that but here's a video I took of the problem. 

https://youtube.com/shorts/ooX1ZO_CC3s?feature=share

[PeterCPC]

I cannot be of any further help. Looks like an issue inside the mount.

[Maclean156]

Thanks for reply. Hopefully someone can help 

[dobblob]

Not sure I can help but I have the same symptoms. The AVX is not the best engineered mount on the shelves.

I wouldn't worry too much. I do astrophotography with mine. With good polar alignment the DEC axis guiding hardly has to do any work and when it does the scope (im)balance seems to ensure the drive is engaging in the same direction.

The slack is nothing to do with the clutches. In mine ,and I have checked it, it is the worm/ring gear spacing. It can be adjusted (many videos around on this) but unless you are doing AP and it is killing your images it is not worth the risk of over tightening.

Too tight can cause damage, too loose may be just an annoyance.

[Maclean156]

Thanks. I know its nothing to do with clutches. But being an engineer it annoys me no end so I want to sort it out. 

[Maclean156]

Took it apart. Soon realised that the worm gear had sideways movement. There are no spacers, just a locking nut and an inner adjustment screw. Released the nut opposite gears and slightly screwed inner thread in until free movement was virtually gone then tightened up locking nut.

Sorted 

Thanks Dobblob for pointing me in right direction. 

Also adjusted the declination so it was easier to balance while I was at it

[Maclean156]

Took about 15 minutes in total to do. It now sounds better when operating too.