6 Inch Newtonian Telescope

Update Jan.29/2021 All my Thingiverse tips are donated to children's charities, so I want to thank those of you who have provided support, and been so enthusiastic! I hope to update this particular model in summer 2021 (this was just the result of a quick hack! If I'd known it was going to be so popular I would have done a much better job). There are some great remixes already emerging that you might want to check out in the mean time! Thanks everyone.

Update Jan.01/2021 Posted Fusion 360 Files for those that have requested them. Enjoy.

Update Dec.28/2020 Improved 4" (102mm) Telescope: https://www.thingiverse.com/thing:4700213

This is a prototype design using a 6" primary mirror and a 35mm secondary.

There are adapters for 20mm and 32mm eyepieces. I may add additional sizes in future but are easy enough to model yourself.

The telescope uses standard 20mm extruded aluminum for the rails and a combination of 1/4-20 (M6 should also work), M5, and M4 hardware as well as generic z-axis or heatbed springs for the Primary Kinematic Mirror Mount, and the Secondary mount. The main mounts use 12mm M5 screw and t-nuts in the rails.

I plan to upload the Fusion 360 files and make assembly instructions available in future, but in the mean time I wanted to make the STLs available for anyone that wants to try and play around with it. I found that the telescope was quite functional with minimal adjustment before going through a proper collimation.

I've included mounting brackets that can be used to attach the telescope to a standard 1/4-20 camera shoe as shown, however I recommend that you use something much more substantial (I just happened to have a camera tripod in the office so this was convenient (at least till I knock it over!) but isn't practical for real use. The design allows for additional rails to be installed so that you can use a Dobsonian mount or an EQ.

This particular mirror has a 750mm FL, but the design should allow a fair amount of flexibility although I haven't done the optical modeling for other f numbers yet.

Note that the clearances are very tight on purpose. Depending on your printer you might need to adjust the flow or under extrusion values to get the clearances you need.

Have fun with it!