Add this to MakerWorld, as I recently succeeded in casting a pen core using the consumable “waste,” and HF TPU is excellent.

I recently started experimenting with turning pens and needed a mold to create my own pen blanks. Initially, I planned to use a typical silicone mold, but it didn’t work out. Out of frustration, I decided to give TPU molds a try. The good news is that they indeed work! So far, I’ve already extracted multiple pen blanks from the same mold, and there’s another one currently curing!

You can find the full instructions on my Instructable page:https://www.instructables.com/id/Simple-Reusable-3D-Printed-Mold/Thanks!

March 2, 2026 – Update: Added a picture of the finished pen made from the pen blank.