Tidy a compass (f.e. Staedtler) in a box

The compass chosen by my son doesn't come with an handy/hard box...

My wife found out a metal box which pretty fits the compass. Though her approach to protect the lead didn't really impressed me! I had to do something... and show that, a 3D printer is awesome, not to say a must have in any house :D.

I put the STL for preview purpose only: there is little chance that you'd have the same compass and box! For this very reason, I did my best to put as many parameters as possible to fit any or