Long time ago I owned a Safe Box made of wood pieces. I redesigned it to a printable version.

Additional material required: 1x tube or bolt dia 4 mm x 13 mm 1x bolt dia 5 mm x 7mm 1x hex screw M3 x 16 mm

1. Print 1x SafeBoxB, 1x SafeBoxM, 1x SafeBoxT, 1x SafeBoxCover and 4x SquareBolts.
2. Press 2 SquareBolts into the 4mm holes of the SafeBoxB (using a small hammer).
3. Press the small SafeBoxM into the SafeBoxB (hole Inside).
4. Press 2 SquareBolts into the 4mm holes of the large SafeBoxM.
5. Press the small SafeBoxT into the SafeBoxM.
6. Take the tube or bolt dia 4mm x 13mm and press it into the lateral hole of the large SafeBoxM.
7. Put the large SafeBoxM over the SafeBoxB.
8. Put the bolt dia 5mm x 7mm into the SafeBoxM hole, it should move easlily up and down through the SafeBoxM and the SafeBoxB.
9. Put the SafeBoxT over the SafeBoxM.
10. Tighten the M3 screw.
11. Insert the SafeBoxCover lateraly into the the SafeBoxT.

How to open the SafeBox? That's secret :-)