Diameter gauges 2-30mm & 31-45mm (1mm increments) with opening angle of 45°, 60°, 75°, 90° & 135°

Disclaimer: If you print this a fdm 3D printer (which you probably will) it might not be so accurate, especially for the smaller semi circles. Also, I don't recommend printing this with a material that has a lot of thermal expansion (such as ABS and ASA) like I did.

Note: Sorry I didn't add numbers under eatch semi circles to indicate their diameter, but there simply wasn't enough space and I was feeling a bit lazy.