Charles' suggestions are right on the money as usual. I've
always avoided hand making domed bangles because you can buy them
so inexpensively, and the work entailed in making one is so
I believe the process used by the manufacturers is somewhat
automated, using large and heavy forming equipment. The nicer
hinged hollow bangles even have a formed inner sleeve, comfort fit
as it were.
The main problem I've encountered in forming objects like this is
comformity of curve. To smooth out all the bumps and other
irregularities and form an extremely evenly curved oval domed band
can be excruciating. If you had access to a hydraulic press such
as that from BonneyDoone Engineering, the project would be
simplified. There are attachments designed for work of this sort.
However, you might need to make some of your own forming tools to
generate the oval rather than a round bangle.
To add to your miseries, you may also encounter warpage as you
solder, pulling the seams apart, or twisting the edges. The
warping can be avoided by frequent annealing during and after the
I wonder if the bracelet could be made by an electroforming
process? You'd need to make a core. There might be a company that
would do this for you, anyone have any suggestions? All you'd need
to do then is make your cuts and install the hinge and clasp.
Hmmm... I'll do a search... Maybe the MJSA can advise us here...
I'm getting some ideas... hmmm
And of course, anti-clastic raising as mentioned earlier by
Marilyn Smith is an alternative. Ettienne in Maine (I forget the
artists name) produces exceptional hollow forms. I've had the
opportunity to work with some of his creations, amazing jewelry!
Once again, the difficulty I perceive with this technique lies in
achieving a perfectly regular surface and oval curve. I believe it
could be done, but might require extensive experience with the
process. I've never tried it, so you can take my advice here with
a grain of salt.
Good luck, making a hollow domed, oval, hinged bangle bracelet
would be a valuable learning experience.