Finder scope Shoe for C8

[Uplooker]

Hi All,

I have purchased a 8x50 finder to replace the 6 x 30 one that is on my Celestron C8. I need a new shoe to match the hole pitch on the scope.

I have searched but I am only able to find ones with fixed hole poistions of approx 20mm. I need something closer to 35mm.

Any assistance or links to a suitable product greatfully received.

Ian

[John]

Hi Ian,

I fitting something to my old C5 that had similar hole spacing. I think it was this one:

http://www.telescope...se_for_SCT.html

There are also a couple on the Astroboot for a lot less £'s that may do the trick:

http://www.scopesnsk...t?needle=finder

These have slots for the fixing screws which can accommodate a range of hole spacings. Might be worth checking with the seller that they go as far as 35mm.

[John]

Just spotted this "Rolls Royce" solution from Baader which will definitely work, but is a bit pricey:

http://www.firstlightoptics.com/finders/baader-universal-quick-release-finder-base.html

[Uplooker]

John,

Thank you very much for those links. Yes, the baader one is a bit pricey, Astroboot one looks the job.

You are an invaluable resource of knowledge, John. You always come through when I ask questions regards bits and bobs. Thank you once again

Ian

[Uplooker]

So, I have managed to get a suitable finder shoe - thanks to John (see above).

I now have the problem that the screws that held the original Celestron finder to the scope are not long enough to attach the new shoe as they are not counter-sunk. The bracket accepts countersunk screws.

So what diameter and thread are the screws that attach the original finder to the C8?

[John]

Hi again Ian

The older C8's used imperial size screws for this - in the manual for my old Celestar C8 they were given as 10-24 x 5/8" (hope that makes some sense - I'm not that great on these engineering things !).

If yours is a USA made one then my guess is that they are the same. If it's a more recent one made in China then that hole size may have changed to a metric equivalent.

[Uplooker]

Hi John,

Yet again you come to the rescue! That is briliant. 10-24 x 5/8" means a number 10 dia. screw, with 24 threads per inch, with the length of the shank being 5/8". I think I am right in saying it is a UNC - unified Course thread, as it has 24 thread per inch rather than 32 tpi, which would be unified fine UNF.

Ian

[John]

I'm glad it makes some sense to you Ian

Hope you can get that finder mounted now.

[Uplooker]

Well, for those that have followed this thread, you are probably wondering how I managed to make a simple task so tortuous.I have finally managed to source the correct size machine screw and believe it or not mounted the 8x 50 finderscope

Thank you to John for all his help and adviceIt turns out that the screws that where used on my C8 to mount the stock Celestron 6 x 30 finderscope are 8-24 x 5/8".

For the uninitiated that means a Number 8 diameter (0.190 inches or 4.826mm) Unified National machine screw, 24 threads per inch (therefore course thread) with a bolt shank length on 5/8"So if you need to get some ask for UNC No.8 5/8"

Because I was using a different finder shoe bracket I needed some screws that were slighty longer. I ended up gettingc 1 inch one and cuuting them down to 3/4"

Hope that helps anyone in the future.regards,Ian

[John]

Not quite as the Celestron manual has it then Ian, but close

I'm glad you have got it sorted. Having the right finder arrangement on a scope adds so much to the pleasure of using it !.