3D-Printed Focus Mask for 12" Truss Tube RC

[derrickf]

I want to check the accuracy of the autofocus routine I use on my 12" RC and a Bahtinov mask seems like a pretty straightforward way of doing this. I decided to try to design and 3D print  a mask despite only having a 230x150x140 print volume and the outer diameter of the mask needing to be in the region of 375mm.

I used the Bahtinov Generator at Astrojargon to generate a drwing of the mask in SVG format then imported that into Fusion 3D as a basis for the final product which I would print 2mm thick in PLA plastic. I added the various bits to the basic mask model to enable me to attach the mask to the front of the Truss tube RC. I then split the mask into 4 quadrants and made some minor adjustments to make the quadrants fit on the 3D print bed, adding some holes that would be used to mate with pins on the external supports that would enable me to assemble the 4 quadrants into a usable mask.

The short video here shows one of the quadrants mid-print on the Flashforge Dreamer:

Baht_Seg_Print.mp4

This is the front view of the assembled mask

and here is a rear view showing the large pins that are inserted into holes in the Secondary support ring of the truss tube - you can see how the quadrants are fixed together using the push fit pins (easy to design since Fusion 3D makes it simple to apply a draft to extruded features).

and finally the mask in place on the RC

All in all, I think it turned out better than I expected.

 

Derrick

[derrickf]

It works

[Dave_D]

Mask for my 10" newt... aint 3d printers great

[derrickf]

Looks good!

[Dave_D]

yeah but your scope is better than mine