A bevelled frame for Hueforge filament paintings. You can make it permanent with the provided printable inserts and a drop of glue, or you can use 8x3mm magnets to hold it together. Be sure to get the polarity right for each pair before gluing them in.

NOTE: I have produced an upgraded version of this frame using push fit right angled inserts instead of of magnets and cylindrical inserts. Here: https://makerworld.com/en/models/64865#profileId-68121

I have included the F360, Step, and STL files for making different sizes. I would avoid simply trying to resize an axis in the slicer as the mitres and inserts will change. F360 is easiest as I have identified the parameter values for you to change length and picture thickness (see the file).

This is my own original model, but the idea is based on a design by Madness3D, but I wanted a bevelled frame, and his was flat.