Small 8mm miter box

Planning to make picture frames using 8mm stock, so designed & printed this miter box. Havent used it yet, but it feels quite sturdy. The tolerances on my old ender 3 are pretty bad, but it feels sturdy and should be functional. 8mm is pretty niche but that would be easy to tweak to cut base boards, for eg, although i guess people miter saws for that.
Anyway, in case this helps.