Ad Astra Observatory

According to my research, the “HS” (”hole spacing”) for the DC11 plate is 16” and 16.5” apart.
The holes are at the ends of the plate only.

I believe they are 1/4”-20 holes.

The DUP is shorter (13.5”) but has a lot more selections on holes.

My design is something like this (except mounted on a G-11).

My plan is to through-bolt an L-bracket to each of the two lower rings, then bolt to the ends of the D-plate to mount up (the D-plate would determine the spacing between the two lower rings). So end holes only is fine by me.

My balance calulations tell me that I needed about 17-18” of plate to bring the balance point between the two lower rings, so DC11 looked right.

So there are 2 sets of holes at the ends? One that’s spaced at 16” and another at 16.5”? Hmm.