Long and floppy

[jambouk]

I've got a second hand Vixen A80Mf I bought a few years ago and have only used a handful of times, and planning to donate it to my local society as a loan scope. The focus tube is floppy and has lots of play in it up and down (not in and out). A previous owner has put some small corrugated strips inside the focus element to minimise the flop, but it is still quite slack. Tightening the screw on the top does tighten things a little, but it still slops about when the focus tube is out a long way.

Is there an easy fix to make it all more snug? What is this corrugated stuff called and where can I get it from to try and put a stip on the one runner which hasn't yet got it attached?

I have purposefully removed the one runner in one of the pictures.

Any help gratefully received.

James

[John]

That looks like a standard Skywatcher R&P rather than a Vixen one. It's possible that Synta, who make Skywatcher, made that particular Vixen.

There are two small grub screws either side of the big tension / lock screw on top of the focuser. They can be used to gently put some pressure onto the drawtube via the black nylon strip which goes between the 2 ribs as you have it in the 3rd photo. You don't need the corrugated stuff (which is a sort of teflon I think) on those two ribs as they don't contact the drawtube.

Here is a link to Vixen's instructions for tensioning their original focusers which should also work for the one you have:

http://miltonhill.us/Tele/Vixen_Focuser.html

Your unit won't have the 3rd grub screw but at it's labelled "do not touch" that should not matter.

I love Vixen's helpful final advice "Please try your best without giving up."

[damnut]

James,

This looks like a task for Graham, suggest you point it in his direction.

[jambouk]

John, you are an absolute star! Fixed. I hadn't even realised there were two grub screws in there. I will buy you a pint if we ever cross paths, and if you don't drink, I'll just have two

Thanks so much.

James

[John]

No problem James - glad it was some use