READ.ME.FIRST

Revised - v2 - mod to Ring part 4 

This zip file contains the STL components for a set of rings for a Celestron C11 Telescope.

All parts can be printed on a 3D printer with 210mm square bed size.

There are 4 separate segments which are linked using 3 link pieces. The final two segments are clamped using a bolt.
The inside edge of the ring in covered in felt to protect the OTA paintwork from scratches etc.
The links are joined to the ring segments using M6, 6mmx25mm bolts with standard nuts
The clamp bolt is a M6, 70mmx6mm bolt with a standard nut.

You need to print two each of the ring parts plus 6 link spacers

The centre to centre spacing between the two rings is 140mm.

There is a choice of two platform mounts. Either a standard Vixen Bevel or a standard guidescope Bevel. These are interchangeable using a M5 hex Allen bolt.

Use brass threaded inserts (M5 for the platform mount and M4 for the instrument clamp on the platforms). 
To fit these, I use a hot air gun or small catering blowtorch to heat the insert. 
Thread the insert onto a long screw, heat the insert and gently push into the hole. Check the alignment is correct then spray with cold water.

Don't blame me if you burn yourself.

I use PLA for all the parts with 30% fill and 1.5mm or 2mm wall thickness. The rings and platform are very strong but will not support more than about 1 kg of guide telescope mass.
This is adequate for small guide-scopes (say max 60mm objective lens size) etc. Again, use your own judgement.

Note: there are a couple of minor anomalies in the STL files, very thin false walls. These can be ignored, they will not be printed. They were not in the original CAD files.

Version 2 has a change to TubeClamp4 to add a second platform

Martyn K
2024-01-27.