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.

In this creative tutorial video, you can learn how to make a DIY Christmas ornament using a bottle cap and a safety pin. The ornament crafted is a miniature train running around the Christmas tree.

A: Both questions are related, so this week’s column is a two-fer. Caps and lids are recyclable in Rhode Island, when attached to the right host. Because bottles can be plastic, metal or glass, let’s ...