what is the preferred hammer when forming D shaped rings on mandrel?
What seems to be the preferred hammer when forming a D-shape on flat
rings while on a mandrel by hitting the ring towards the edges. (Such
as making a wedding ring) I know that some people can make this shape
by hand rather than using half round rollers. Are the using forming
hammers, ball peen, etc?
While we are on that subject. I also am curious about the method of
forming half round wire with a flat rolling mill by putting copper
plate between one side of the round wire and then running it through
the rolling mill. I read about that but there was no mention of how
thick you should try of a copper plate. I assume the thicker the
copper plate the better it will preserve one side of the roundness of
the wire?
I have a large Durston rolling mill that has plenty of square wire
rollers and flat rollers but no half round. I was wondering the
different ways I could try at forming D-shaped wire, (for rings).
To make D shaped rings you need a D shaped mandrel.
Or do you mean D section wire?
So first of all to make D section wire, there area no of ways.
Excluding special tooling for mass production, a one man band will
usually take round wire and using a flat faced hammer, forge it down
to shape in a half round grove in a piece of steel.
How to make one of these is another lesson.
Square section wire is more difficult to get to the D section this
way.
All the Durston mills Ive seen and on mine has the roll shafts
extended on one side to take extra rolls.
Mine came with a pair, one flat and the other with 3 half round
grooves.
Durston will supply you with these rolls.
Will make your life a lot easier.
Dont use copper sheet in your mill, you need to use the hardest
sheet you can find. this will enable you to use a thinner sheet.
Use spring steel, say, 1/16th in thick.
As to forming a circle with your half round wire on a ring mandrel.
a soft leather mallet of what you should use.
any hammer harder than the D section wire will mark the wire.
Richard- Half round wire is easily available at most any metals
supplier.
To make it yourself, take two wires, solder just the end that you
will be pulling with your draw tongs together, taper, and pull
through a round draw plate. If itâs too heavy to pull by hand, I use
a draw bench. No copper plate necessary.
To bend for a shank use a rawhide, or horn mallet. Metal hammers
will distort. Start bending the two ends before you bend the middle
so you donât have a curve with two flat ends where you want your
solder seam to be. Run a saw blade through the seam for a nice tight
fit. Solder, or weld together. File and emery only the inside, not
the outside or edges. If you file the outside it will crack when
rounding up. Then round up on a mandrel again with a non marking
mallet. I then jam the ring on an inside ring polishing stick, turn
on the motor and use emery to smooth. Then polish.
The short answer is. whatever hammer works. I think Iâd probably
reach for a reasonably sharpish cross-peen. Say 1/8" radius on the
working end.
If youâre trying to make half-round wire, bashing it out against a
mandrel is just about the last way Iâd think of to do it. (just
about guaranteed to ding up your mandrel, for starters.)
A better answer is to make half-round (D section) wire first then
make a ring out of it.
Couple of ways to do that, depending on what gear youâve got.
If youâve got one of the big Durstons, youâve probably got the studs
for outboard rollers. Yes, half-round rolls are expensive, but so is
time. Just get the rolls, if you can.
Next step is a round wire drawplate. Take a bit of wire a bit larger
than the thickness of the âDâ you want to end up with, and fold it
in half. Solder the joined end together, for about an inch. (splay
it out into a âYâ to prevent it soldering beyond the point you
want.) Forge/file a taper onto the soldered bit, so you can get it
through your drawplate. Draw it down a couple of times, until it
becomes the âDâ section you want. The trick to it is that you stick
a bench knife between the wires on the backside of the drawplate.
Set the back edge of the knife against the back of the drawplate,
and set it so that the blade is either vertical or horizontal. The
reason for the blade is to keep the wires from twisting around each
other as they go through the drawplate. (youâll end up with a
barberpole without the knife.) You will have to do some test runs in
copper to see what size starting wire you need in order to end up
with the size you want.
Iâve never heard of running wire between the flat rolls and a sheet
of copper, but thereâs no conceptual reason why it couldnât work.
Iâd use pretty thick copper. The point of the copper is to cushion
the bottom (âDâ) part of the wire, so it needs to be at least as
thick as the âDâ section. Youâll probably get a sort of squashed "D"
or fat-sided oval, rather than a true half-round profile.
To make D shaped rings you need a D shaped mandrel.
Interesting range of options⌠To make a single low-dome, 1/2
round, âDâ shaped, whatever words people like, I just make a ring
out of rectangular stock and file it down. Takes 10 minutes or so,
and I can make any profile I want⌠For lots of them there are a
multitude of options, starting with molding and casting.
take round wire double it over itself run through consecutively
smaller rollers, unbend,clean up. done! there is also a thread from
about 3 years ago in the Orchid archive as this has been discussed
before. rer