Help with "length of wire to make a ring" calculation

It is OD minus one thickness time Pi Basically you are using the "mean" diameter. Randy

That's going to be close but it assumes the compression side and tension side of the bend yield equally. I _suspect_ that mean circumference will be a smidge too long. Perhaps someone with experience will inform us all.

Ted

Randy Zimmerman wrote:

Ted Edwards wrote: That's going to be close but it assumes the compression side and tension side of the bend yield equally. ^^^^^^^^^^^^^ I think this is correct. If I were doing this, I think I would wind the wire around a mandrel, and cut the rings off the coil one-by-one. The manage spring-back, I would either anneal the wire in place, before cutting, or start each cut under tension, so after it is released, it can be closed to the right size.

Or, by trial and error, you could find a mandrel size that produces a ring of the required size AFTER spring back.

It might be at that but you are going to need some pretty accurate mesuring and cutting devices. Several years ago I was involved in production rolling of plate rings ranging from 1/4 inch to 7/8 inch thick plate from 24 to 60 inches in diameter. They had to match machined rings. Circumferences I called up were calculated size on mean diameter minus 30 thou to ensure a match or slight gap for welding. We checked with our Pi tape to final diameter and the match was more than satisfactory. Randy

Randy Zimmerman wrote:(clip) We checked with our Pi tape (clip) ^^^^^^^^^^^^^^^ I think I have a Pi tape, but I never knew what to call it. It reads diameter when wrapped around the circumference, right?