How tight should rings be?

[LewisM]

Bit concerned about some rings I got today - the tube diameter is 5.09", and the rings would SEEM right, and are felt lined, but when tightened, the bolt goes through too far on the other side and runs out of tightness against the other side.They HOLD the tube, but you can physically turn the tube in the rings, and you can slide it (with a little effort). I am concerned that at high altitude settings, that the tube may slip.

I will endeavour to find some tighter rings (won't need much), and may add in another layer of felt for now, but how tight SHOULD they be? I know not "tube bending" tight, but how far?

[asimov (John)]

Just tight enough so that the tube doesn't slip down in the vertical with all your equipment hanging out of the focuser of course. Adding another layer of felt should just about do it I'd think..

[LewisM]

Yeah, just glued on another layer of felt. Here's hoping!

[leon]

Yep I reckon asimov nailed it, just an extra layer of felt will do the trick.

Leon

[Kunama]

That sounds like a new scope Lewis.........129.4mm rings sounds like an ES 127 Apo

[multiweb (Marc)]

Not too tight. I had the collimation going off on a newt alu body that was squeezed a little too much. I gues it moved the spider vanes slightly.