[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 ...

One of the greatest things ever invented to annoy teachers and help you day-dream at work is undoubtedly the clicky pen. Of course a ‘clicky pen’ is actually called a ‘retractable pen’, and they have ...

The pen is perhaps one of the most momentous discoveries ever. While there is no concrete evidence on when the first pen was discovered, history books point out that the first ever pen was a dip pen ...