Finder scope disassembly??

[PeterW]

Any idea how the back part of the typical 9c50 finder scope is held in... ?? I have one and a “50mm guide scope” that is the same with an open back. I was to repurpose these, but I need to remove the back section. Tried to unscrew... nothing budged, could be glued? I’d prefer not to get a saw out in case I want to return them to their original form. Ideas??

 

Peter

[lenscap]

The eyepiece assemblies on my Skywatcher & Orion versions were screwed into the main tubes. They are easy to cross-thread though so I would put on a rubber glove & apply as much torque as possible.

[Peter Drew]

+1  I've unscrewed a few, not always easy!        🙂

[Captain Scarlet]

I have just such a (SW OEM) finder-scope which is surplus to my needs. I’ll give it a go and see how easily and how (and if...) the rear plate comes off...

[Captain Scarlet]

... simply unscrews, as multipl-y suggested above. Mine was barely torqued up, loose in its thread in fact.

M

Edited November 24, 2020 by Captain Magenta

[PeterW]

Need to eat some spinach (popeye style) and have another go...

thanks

peter

[vlaiv]

I have 50mm one and 30mm one that are currently surplus - both unscrew easily.

50mm one has two threads - one that removes eyepiece and one that removes complete back plate.

[fozzybear]

Peter,

With my Celestron  9x50 one I put the eyepiece end minus eyepiece in some hot water for 10 minutes then able to unscrew the adapter

Andy

[PeterW]

Hmmm... the 9x50 version unscrews nicely with finger tips.... the 50mm guider version won’t shift even with bits of rubber wrapped round the tube to help grip. Might even have gently used whacked it too. Right I’ll put the kettle in... to heat the end... a cup of tea will follow, especially if nothing moves!

Peter

[fozzybear]

On ‎24‎/‎11‎/‎2020 at 21:05, PeterW said:

Hmmm... the 9x50 version unscrews nicely with finger tips.... the 50mm guider version won’t shift even with bits of rubber wrapped round the tube to help grip. Might even have gently used whacked it too. Right I’ll put the kettle in... to heat the end... a cup of tea will follow, especially if nothing moves!

Peter

Peter,

How did you go on with this? a success or more drastic measures?

Andy

[PeterW]

Hot water resulted in a damp finder and nice cup of tea. It seems the normal ones unscrew fine, the CCD guider one has a very stubborn block at the back that doesn’t work any to move. I’ll have. Second finder one soon, so I can ignore the guider one. Then I can continue my experiments. It maybe that a hacksaw may have to be involved... though only if there proves to be sufficient space for the diagonals I want to use. Then it’s an ATM project, not a disassembly.

 

Peter

[fozzybear]

7 minutes ago, PeterW said:

Hot water resulted in a damp finder and nice cup of tea. It seems the normal ones unscrew fine, the CCD guider one has a very stubborn block at the back that doesn’t work any to move. I’ll have. Second finder one soon, so I can ignore the guider one. Then I can continue my experiments. It maybe that a hacksaw may have to be involved... though only if there proves to be sufficient space for the diagonals I want to use. Then it’s an ATM project, not a disassembly.

 

Peter

Peter,

Have you a photo of it

Andy

[PeterW]

The tea of the CCD finder? One of these... https://www.astroshop.eu/optical-finders/orion-mini-50mm-guide-scope/p,23580

 

Peter

[fozzybear]

I had a problem with my OVL FF for my 72ed and had to shock it with cold yep put it in the freezer less the lens element of course. could give that a try