3D printable Bahtinov Masks

[Stub Mandrel]

I've put STL files for three sizes of Bahtinov mask from Zeiss Sonnar up to 130P / 130P-DS up on my website at:

http://www.stubmandrel.co.uk/astronomy/147-3d-printable-bahtinov-masks

The sizes are such that you should be able to make them fit any scope or lens from 2 " - 6" (~48mm to 130mm aperture) overall diameter by scaling them in X and Y.

They are not a close fit, they just 'hang there' so as not to disturb the focus/pointing when you lift them off.

[Bizibilder]

Good use of a 3D printer!!

[steppenwolf]

One of the best uses for them I've seen so far - excellent!

[Mr Spock]

Excellent printing!

[Stub Mandrel]

The 130p-ds mask appeared to give me a sharper result than the one I hacked from plastic. I was inspired to do this after buying a decent 150PL one from FLO (at an excellent price!) which also worked better than my knife-cut one. It seems dead straight edges aren't critical, but they do help as a more defined pattern is easier to get just right.

[jiberjaber]

Thanks for this, I had to scale the small one up a bit (a few mm) but it fits nicely (not tightly ) around my finderscope  

[iapa]

shame I don't have a 3d printer, otherwise I could run a set of for all my various OTAs and lenses

<sigh>

[Chriske]

[Richie092]

I was only thinking today that there must be files (InDesign?) for these I could use with my laser cutter. Do you know if these can be converted to .ai?

[Stub Mandrel]

3 hours ago, Richie092 said:

I was only thinking today that there must be files (InDesign?) for these I could use with my laser cutter. Do you know if these can be converted to .ai?

I don't know... I imagine the easest thing would be just to copy the design in your favourite drawing pogram, its pretty simple really. Nothing is critical - a Y-shaped twig works so anything vaguely right with slits at three angles will function.

[Richie092]

Oh I thought it would be some exact scientific measurements. 
 

a twig I can do 😑

 

[Stub Mandrel]

10 hours ago, Richie092 said:

Oh I thought it would be some exact scientific measurements. 
 

a twig I can do 😑

 

There are theoretical arguments for the optimum shape for a given aperture/focal length. After trying a large array of random masks, I can confidently say that though the detail may affect brightness and spike contrast anything that looks like a bahtinov mask will work like one.