The Boy Mechanic, Book 2: 1000 Things for Boys to Do
“ Occasionally an amateur has need of brass rings of round cross section, and if their construction is not understood, the task is a difficult one. If a piece of brass tubing, an old bushing or a cored piece is at hand, a part of the work is already done. If not, a piece of stock with large enough outside diameter should be chucked in the lathe and drilled out with the right size of drill. A tin or pasteboard template should be prepared the size of the ring section—a half circle is best, and it is easiest made by drilling a hole in the tin and cutting it in two. ”
