Quote:
Originally Posted by ralph1
Yes, the mount is a GEM. I did consider a horseshoe or yoke mount but I decided it wouldn't be portable enough, if a 2 metre long telescope can ever be considered portable. Another idea I had in mind was a dobsonian with the azimuth axis pointed at the SCP but when this popped up I thought I would use it instead. Sorry, no pictures at the moment but I should be able to take some tomorrow. When I got it there was a box full of goodies, one of them being setting circles from astro-optical supplies so the mount could have originally come from there too. I've had a play around with it but I can't see how to put them on, or even anywhere to disassemble it so the setting circles could be unrelated. Possibly a surrurier truss would be good, it would have a mounting point in the middle for the GEM, ultimately the tubes purpose is to hold the optics in alignment. Another possibility stolen from garyseronik.com  is a simple metal bar with the mirror and focuser at each end.
Ralph
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I doubt Gary Seroniks single strut will work for you at 2 meters. You're going to experience a lot of Collimation issues due to flexure of the support strut over that distance. I'd suggest a reasonably light serurrier equivalent for best rigidity, collimation/optical alignment and vibration damping.
If I'm not mistaken the pics of the mount are one of the Samson (?) mounts Astro Optical sold. Mark or others could confirm how much leverage load they can handle but I wouldn't think that would be suitable either for your planned OTA. It's not the weight which will be your main issue but rather the length of your OTA will act like a long lever magnifying vibrational effects at the extremities even for a very light OTA. You may find the OTA will develop a resonating effect which may be difficult to damp out even in light breezes. You could hang a light chain from the OTA to absorb vibrations.
As you have this mount already no doubt you'll do your best to make it work but an altazimuth or other mount where the centre of gravity is between bearing points (English yoke, horse shoe, split ring) all of which can easily incorporate large bearing serfaces that damp out vibration, will be much more stable for your long OTA than a cantilevered design like a GEM.