GSO 2'' diagonal locks onto my SCT LX90 8''

[BarneyMaroon (Tony)]

My GSO 2'' diagonal seems to bite hard on the rear ring of my SCT. This happens when I loosen it off to rotate it down for the kids to use and then give it a small twist to tighten (or vice versa). It seems to go from a gentle firm hold, to a rock hard bite that I have to muscle off (and generally lose my alignment).

It got so stuck once my efforts actually unwound the tread on the SCT - so the thread and diagonal were attached together.

Anyway, I was going to try some silicon lube (for my bike chain) on the thread, but thought that the knowledgeable readers on iceinspace might have a better suggestion.

[casstony]

I'd use a dry lubricant, perhaps a dry Teflon lube that is in solution and can be painted on the threads? You could use spray on Teflon lubricant provided you plug the rear port to avoid getting any inside the scope.

[Nikolas (Nik)]

Or spray the Teflon lubricant on a small rag and wipe it onto the threads

[Merlin66 (Ken)]

Don't use WD40,grease or any silicon lube!!!!
They have a high potential to outgassing and impact on the optics - don't take the chance.
A tried and proven methods is to give the threads a very slight wipe of shoe polish (your choice of colour!)
Guaranteed to work.

[raymo]

My GSO diagonal on my orange tube C-8 did the same. I kept a small leather strap wrench handy. No amount of lubricant helped in the least.
raymo

[iborg (Philip)]

A suggestion, try a close look at both threads with a magnifying glass.

Perhaps there is an edge somewhere there that is 'locking in' with that last bit of pressure.

If there is, then running a steel edge across it my take the edge off.

A steel rule should do.

Philip

[brian nordstrom (As avatar)]

Yes I second the boot polish , the 'Kiwi' brand work,s well but remember only a tiny amount or you will be forever getting it on your hands �� but it is the best.
Brian.

[JimsShed (Jim)]

On my c.925 SCT I replaced the visual back with a 2" Baader Click-lock and switched over to using a regular 2" diagonal. I like to sit down when I'm at the scope and the Click-lock makes doing this very easy. Just an idea if you get the urge to buy a solution

[iborg (Philip)]

Hi Jim

I am interested in doing the same thing with my LX90 8".

Would you mind letting me know what the length of the Baader+diagonal is?

I am concerned about clearance.

Thank you

Philip

[doug mc]

I have a 2 inch GSO sct diagonal and it can lock as well. I found that grabbing the diagonal body and the ring together and applying most of the force on the diagonal body to lock or unlock works.

[Merlin66 (Ken)]

Hmmm
From all the replies I can only think that the SCT thread on the GSO parts is not 100% compatible. Very strange.

[BarneyMaroon (Tony)]

This is a great forum, if only the all internet forums were this useful! Thanks for your input all. I will inspect in the light to see if I can see anything. Boot polish or a new bit of gear ay?

[raymo]

The little strap wrench did the job, much cheaper than a new bit of gear.
raymo