I occasionally use stamped or pre-formed pieces from Stuller, Rio,
or Metalliferous when they provide a shape I can’t get (or can’t
figure out how to get) any other way.
One of my favorite shapes is a scallop shell, like the famous “venus
on the half-shell” Botticelli painting (yes, I know that’s not the
REAL title, but everyone will immediately know the one I’m talking
about). It’s basically a circle that has been corrugated “top to
bottom” and then made concave. At the top of the shell, the
corrugation is much closer together than at the bottom, and the
corrugation ridges are usually quite small. I’ve used these pieces
up to about 1.25" in diameter. You can see a picture online at
www.stuller.com http://www.stuller.com/ , product # 3886. (This
isn’t exactly it, as this one has a flat area at the base of the
piece and the ones I use have corrugation extending all the way to
the edge.but it’s close.)
However, I’ve never succeeded in replicating them. When I corrugate
using the bonny doon brake or the industrial tube wringer, the
corrugation is MUCH bigger than on these pieces. And even if I
crimp along one end, it still doesn’t give the same effect. Doming
the piece then “flattens out” the corrugation.
SO. have any of you made these pieces and, if so, what set of
techniques did you use? I’d love to make them in a variety of sizes,
as well as some variations, since I like the design.