I've made a major revision to my magnet pen design that I released last year. The new version is redesigned so that you can print a pair of pens, along with a Gridfinity bin for them, in a single 4-5 hour print. It also now prints without supports for any part, and includes a sight gauge to let you check how many magnets are left. As you can see, it makes press-fit magnets extremely quick and easy, and glue-in ones are likewise straightforward. Despite being printed out of PLA, the pen is super robust - I haven't been able to break one yet, so they work great for even the tightest press-fit magnets. Having a color-coded pair of them makes it easy to make sure you're getting the right polarity for every magnet, too. An AMS is highly recommended but not mandatory - without the text there's only 3 color changes.

Sneak peek of the first prototype of a vertical rack for clamshell boxes.