Do you want to design something to match existing threads on a bottle, or a cap? It turns out there’s an easier way than reaching tiredly for the calipers and channeling one’s inner reverse-engineer.

Recently, one of [Eric]’s clients asked him to design a bottle. Simple enough for a product designer, except that the client needed it to thread into a specific type of cap. And no, they don’t know ...

We may earn a commission from links on this page. Instructables user Inspiredwood has a great tutorial on how to make a conventional ship-in-a-bottle, but he also reveals an interesting tip from his ...