Guidescope mounting.

Babalyon 5 · #1 13-09-2008, 12:17 PM

Howdy all!
Ive got my new EQ6 set up to go on the pier out the back(semi permanent) and have been drifting it in with my 4in scope. I was going to use my 10in reflector(aperture fever) as I just love this scope and have had the guide scope on top of the 10in. I tried to search for side by side setup info but didn't really find too much except a few pictures. Guide scope is an 80st Orion, so weighs very little and is quite tiny really(its so cute).

Would I have to shift the main scope sideways a bit before mounting the guide scope considering the weight difference? If I did or didn't, how would this affect the balance and anything else I haven't thought of yet?

peter_4059 (Peter) · #2 14-09-2008, 06:59 PM

I've got a 10" Newt mounted side by side with a 4" f5 guide scope on an EQ6. You need to have the larger scope closer to the centreline of the mount to balance things up. I needed 4 skywatcher counterweights to make the balance work.

Babalyon 5 · #3 17-09-2008, 06:08 PM

82 views and one reply! That's great!

AlexN · #4 17-09-2008, 07:03 PM

I have done a test fit up of my C11 + M102 on my EQ6 today using an ADM side by side bar.. Took 4 counterweights to balance it, and as peter said, the large scope sits ever so slightly off center of the mount, as the guide scopes weight is pretty minimal compared to that of the C11.

mounting guide scopes on top of the primary imaging scope can cause flexture problems with heavier ota's, which only leads to headaches and hysteria...

Also, guidescope rings are a must, My ST80 is in a set of ADM 100mm guide scope rings and will likely be used as the guide scope more than the M102.. Weight is a problem!!

peter_4059 (Peter) · #5 17-09-2008, 07:03 PM

Not happy with the reply?

AlexN · #6 17-09-2008, 07:08 PM

I was wondering that myself, but wasnt going to say anything Peter... Makes you wonder why you try to help sometimes...

Babalyon 5 · #7 17-09-2008, 07:51 PM

I am happy with your reply and grateful that you did.

I sought a higher level of input and advise to see what others are doing to gather as much information as possible before making my decision.
And THANKYOU AlexN for your unneeded and unsolicited reply.

peter_4059 (Peter) · #8 17-09-2008, 08:19 PM

Good luck.

gregbradley · #9 17-09-2008, 11:19 PM

One point. Mounting a guide scope on top of large diameter scope can cause serious balance problems.

I put a William Optics 80mm on top of an RCOS 12.5 inch once and it burnt out the motors of an MI250 mount. It was at balance when horizontal but once it went to an angle the balance point shifted a lot causing too much strain on the motors.

So if you do that I'd check the balance at various angles. It may be a matter of positioning the top scope at the right point so the weight is more equally balanced over the balance point of the main OTA. Not sure.

So either a very light top mounted scope or side mounted guide scope like with a tandem bar. (I currently have a 10 inch scope with an Astrotech 66ED mounted on top and it is a small and light scope and balance does not seem to be an issue and I am getting great gudiing from it).

You can also mount a little guide scope using a Losmandy dovetail adapter mounted to the guide scope and it can attach to the front of the dovetail plate of your main OTA if you have a bit sticking out the front.

Works great with a Tak FSQ (which is a small, compact scope).

Greg.