ST102 focuser movement

[Maxrayne]

Currently have the SW ST102. The focuser unit has a fair amount of lateral and vertical movement. I've stripped the focus assembly down but can't see where the problem is. Does anyone have any ideas on this?

[JamesF]

My recollection is (because I can't check right this moment) that there are a couple of grub screws on the top of the focuser body that press on a teflon(?) pad which in turn presses down on the top of the drawtube.  If there's a lot of movement in the drawtube it may be that those screws need some adjustment.

James

[Peter Drew]

As JamesF says, the adjustment facility is provided by the two very small grub screws.   ?

[Maxrayne]

Just had the assembly apart, against my better judgement (because I always have bits left over when I put it all back together) and I "think" I've found the culprit. At 120 degree angles are the three white...shims I guess they're called, that act as guides for the drawtube. The top one seems to be missing. Hopefully you can see in the image what I mean.

[Maxrayne]

Just had another look. Yeah I can see those holes...well, at least I know how it all comes apart and goes back together now ?

I now have no play as well ?

[Alfian]

I assume it has/had teflon strips that act as guides/shims. When I first got my new 130 EQ (some years ago) I had a problem which I traced to one teflon strip being displaced and another no doubt still being somewhere on the assembly plant floor. Fortunately its a relatively easy fix.

[JamesF]

Yup.  Small sheets of teflon can be bought from ebay/Amazon if a replacement is required.

James

[Maxrayne]

Thanks guys. Tightening the grub screws has done it for now, but I obviously do need to replace that teflon strip