My youngest has a cute little wooden Rocket puzzle, made by a French company called Janod. Sadly, at some point, we lost the nose cone part, so I designed and printed a replacement.

Rocket cone

It's substantially based on one module from an OpenSCAD "Nose Cone Library" by Garrett Goss, which he kindly released to the public domain.

I embellished the cone with a top pointy bit and a rounded brim. I also hollowed out the bottom to make space for a magnet. Originally I designed an offset-from-centre slot for the magnet, the idea being, you would insert the magnet off-centre and it would slot into position and be partly held in by the offset, and you could then stick a blob of glue or similar to finish the job. Unfortunately I had a layer shift during the print, so that didn't work. I reamed out a small alcove instead. The white trim is adapted from the lid from some kitchen herbs, trimmed back. I secured the magnet and glued the lid over the bottom.

Here it is: rocket.scad. My contributions are under the terms of Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0).