The Spool Safe

This cleverly disguised safe is designed to fit snugly within a reused filament spool, leveraging the empty core to maximize storage without attracting unwanted attention. Faux filament lines on the spool’s exterior mimic real 1.75mm filament, creating a realistic and convincing illusion that effortlessly blends into any workspace. Inside, there is surprisingly generous room for securing your most important items, from small electronics to personal documents. By repurposing an old spool in this creative, eco-friendly way, you can ensure your belongings remain well-hidden and protected.

I have included a version compatible with both a standard cardboard spool as well as an empty bambulab spool. The bambulab version does not require glue so it is still reusable.

The cardboard model includes a m4 screw slot for secure closing and transportation. Any m4 bolt will work up to ~30mm and specify a “countersunk” flat-head screw will sit flush. If you can match the spool and bolt color it is almost impossible to see at first glance!

While I recommend a .12 layer height for the best screw threads and filament lines, I believe all the way up to a .28 layer height should work. *not tested*