Use the OpenSCAD script to generate whichever mount dimensions you need.
Provide the diameter of the outer tubus onto which you wish to mount the plate along with the width, length and offset of the plate you need and the rest is done by this script.
Fixing the mount to the tubus can be done using velcro strips, rubber bands, epoxy - choose based on your needs.
Initially I created this to have a good fitting mount for my phone to use AstroHopper. But since there is often a need to attach some equipment to telescopes - it might make sense to have this available.
The author marked this model as their own original creation.