[Bill Hammack], aka the [EngineerGuy] is at it again, this time explaining how retractable ballpoint pens work. In this excellent video, he describes the simple (but remarkably sophisticated) ...

[u407]’s 3D printed Signspinner was created as a clean/dirty indicator for a dishwasher, and at its heart is a mechanism that works a lot like that of a retractable ballpoint pen. Every click of the ...

We independently review everything we recommend. When you buy through our links, we may earn a commission. Learn more› By Elissa Sanci Elissa Sanci is a senior writer who has reported on label makers, ...

Shigeru Ban has designed a retractable, refillable "SCALE" pen for ACME Studio that was inspired by the architect's ruler. The aluminum pen, designed to fit comfortably into your hand, serves as a ...