Back to Ganoksin | FAQ | Contact

Rolling Mill Basics - The Square


#1

Orchidians,

This forum is all about sharing, and since much of my teaching for
the past 30 years has been about the rolling mill, I thought that I
would put out some regarding how to use it. I am planning
to put out a weekly “How-To” tip on a particular aspect of the
rolling mill, and I hope some of you will find it useful. My
suggestion would be to practice in sterling silver, as it rolls
beautifully, and is cheap enough to experiment with.

Ground Rules… Your rolling mill should ideally be a combination
mill. Said another way, it needs to have both flat as well as grooved
rollers. Making half-round stock will most likely need side rollers,
if that is an option on your mill. The rolling mill rollers should be
very clean, unpitted, and wiped free of surface grit or oil. DO NOT
run your flat rollers all the way together. This is not necessary,
and can lead to roller damage if small bits of metal or grit get
trapped between the stuck rollers. Making wire stock with rollers
touching is guaranteed to produce “fins” on your wire, which is
usually undesireable. Make sure all metal run through the rollling
mill is annealed(soft) and DRY.

“The Basic Square”

This wire shape, the Basic Square, is the start to making all wire
and bezel stock. When planning your “goal” wire or bezel shape, you
need to know what it’s final dimension will be, both in width and
thickness. Your poured round ingot, ideally, should be wider than the
final shape you want to end up with. ( However, there are tricks to
widen this if needed) Start with your mill open, and visually find
the groove which “matches” your ingot. If anything, you want your
round ingot to appear slightly larger that the groove you are
starting in. During the first roll through the mill, you should feel
a light pressure on the handle, and should see small flat areas form
on the ingot when run through. This first pass is just to get the
right adjustment on the mill.

For ease of description, let me describe this “square” shape we are
making as having a 3-6-9-12 orientation, like the face of a clock. As
the square stock emerges out the other side of the mill, it will have
pressed both the top and bottom corners of that ingot, the 12 o’clock
and the 6 o’clock position. Now, you will want to run that same ingot
back through the same groove, but now pressing the 3 o’clock and 9
o’clock position, or the other corners you didn’t press the first
time through. Stay in the same groove. The CORNERS of this square
shaped ingot will always be facing UP when going through the grooves,
not the flat sides up. Without re-adjusting the mill, you will have
run the ingot through the groove, and before running it back through
the same groove, you will have given it a quarter turn, so that by
running it back and forth through the mill, in the same groove, you
have pressed all four corners, making a square shape.

Now, turn the top adjusting handle on the mill a half turn closed (
counter-clockwise ). Repeat the rolling of the ingot through the
same groove, and back through the same groove, after having turned
the stock a quarter turn before that return roll. The ingot is now
getting a nice, regular square shape. If your final shape needs to be
narrower, then run through the same groove after having tightened the
mill another half turn. With sterling silver, you can easily make 3
back and forth passes, adjusting the mill closed a half turn before
each set of passes, before you will need to anneal. During this
process, if the rollers start to touch, then open up the mill a few
turns, and start the process on the next smaller groove, starting
that new groove with minimal pressure to get the adjustment of the
rollers right before “committing” the entire wire to the mill. If you
see FINS forming on your stock, then you are in the wrong groove,
pressing it way too hard, or trying to go way too fast making your
wire.

All metals will have different “personalities”, regarding how much
you can roll between annealings, as well as how much you can tighten
the mill between passes before getting stress fractures. “Practice
Makes Perfect”, as they say.

A word of warning about gold alloys… there are 2 basic alloys, one
for casting, and one for rolling. The casting alloy is too brittle to
roll, but the rolling alloy can be cast. Any amount of casting alloy
in your ingot will very likely lead to cracking, in my experience. I
only buy rolling alloys, for both my casting and rolling needs.

Next Week…“Tapering Square Stock for the Draw Plate”

Jay Whaley UCSD Craft Center


#2

Hi Jay

How Wonderful! Gratefully accepted!

Can hardly wait until you get to the part where impressions are made
in the sheet silver using manila folders! I like using hand made
paper, also!

Thanks, thanks and more thanks for all the info you are going to
share!

Rose Marie Christison


#3
This wire shape, the Basic Square, is the start to making all wire
and bezel stock. When planning your "goal" wire or bezel shape 

I don’t want to steal Jay’s thunder - very nice beginning to a useful
series, I’d say. To elaborate some on what was Helen’s post, though.
Using the drawplate IS to some degree “cheap”, though I can pull 50
kinds of wires, myself, including off-gauge sizes - I have a
collection of drawplates. It may surprise readers, but I have never
used a drawbench. I knew people who had one because they made
hand-made curb link chains - like ID bracelets. I’m sure they’re nice
but they take a huge amount of space to have one just for the
occasional bit of 18 gauge wire. Which is to say it’s a nice luxury
(unless your work really requires it, like the chain makers), but
it’s not necessary, usually. A big vise on a stout bench and
drawtongs will get you a lot of wire. To me probably the most
frequent thing I do on the rolling mill is to make rectangular stock.
The mill makes “wire” and “sheet” which I put in quotes because often
the wire is a chunk, like 4mm wide, and the sheet could more properly
be called a slab. If you roll a square wire into a shape to make a
wedding band, you could say it’s sheet, but it’s more proper to call
it rectangular stock - same with many of the building blocks for
constructing jewelry. Somebody somewhere (Revere?) even calculated
how much width and length can be gotten from the square size on a
mill - most people just need it “about yeay big”. One big tip is that
you can get much more width out of a square by forging it - hammering
it - first. Anyway, as has been said, the mill is much more than a
way to make your own 20ga., it’s how to get any size and shape you
want for what you want to do - and that’s where experience comes in:
"How much length and width do I need to start with to hit this piece
right on 2.6mm x 1.8mm? Have fun…

http://www.donivanandmaggiora.com


#4

Dear Jay,

A brilliant idea, thank you. I’ve just purchased a combination
rolling mill but thus far have not really known what to do with it. I
was planning to make the most of my growing scrap pile of sterling
silver by melting, casting ingots and rolling, so your articles will
be of great help.

Thanks again, and I look forward to reading future installments.

Helen
Preston, UK


#5

I missed most of this thread Jay but I also just bought a rolling
mill and own a big pile of scrap. I’m thinking your brilliant idea
might apply to me as well.

Please share, Many thanks,

Cyndy


#6

Thanks John,

I’ll have to bite the bullet and put the mill to good use. I got the
impression that the draw bench is more of a luxury that you can get
by without but it seems as though having some basic draw plates for
use with the bench vice would be a good idea, to get consistent wire
with uniform strength. I’ll get to know the mill first I think and
then assess what I need thereafter. You can never have enough tools!

Helen
UK


#7
was planning to make the most of my growing scrap pile of sterling
silver by melting, casting ingots and rolling, so your articles
will be of great help. 

I’ll just point out one other advantage to using the mill, and that’s
that it puts out “gauged” material. Say you need to put a floor into
a channel set baguette setting, and the baguettes are 3mm long. So
you just roll out a piece of square stock to a rectangle that’s 3.25
or 3.5 mm wide (allow for filing), and the proper thickness, and you
have “automatically” made your floor stock. Same for the walls - they
need to be 4mm high by.5 thick, so you just roll that out, and
there’s your wall part, exactly sized. These are things that are
difficult if not impossible to foresee in the sense of buying ready
made mill products, plus a job like that might require 10 different
little bits of metal that are slightly different. Yes, you could file
down stock to size - now THAT’S a chore. You could live with what the
refiner gives you, too, but I won’t even say what that means -
limited, at best. Very powerful tool, the rolling mill.

http://www.donivanandmaggiora.com


#8

Hi Guys,

I’m with John on his one. I draw lots of wire, different
sizes/shapes & have never used a draw bench.

I put my drawplate in a vice that is attached to a sturdy work
bench. I put the droplet in the vise so the row of holes to be used
is just a little above the jaws of the vise. This way I can place a
piece of felt saturated with oil on the top of the vise jaws so the
wire will rub through the oily felt as it goes through the
drawplate…

To keep loops & kinks out of the wire that’s coming into the
drawplate I uncoil it & be sure there are no loops & kinks in it The
it’s run through a series of guides (staples) in a piece of wood
about 4 feet long. just before it enters the drawplate. The piece of
wood lays on the bench so it’s perpendicular to the drawplate… I
grasp the output side with a pair of visegrip pliers & pull the wire
through, again staying perpendicular to the drawplate. The longest
piece of wire I’ve drawn to date is about 40 feet.

If you don’t keep the wire perpendicular to the drawplate as it
enters or leaves the drawplate, the wire will tend to have curve in
it after it’s drawn. When drawing wire I put a little magnet above
the hole being used. This way I don’t have to go looking for the hole
that was used. I just find the magnet & go to the next hole in the
drawplate.

Dave


#9
I'll have to bite the bullet and put the mill to good use. I got
the impression that the draw bench is more of a luxury that you can
get by without 

That’s been my experience thus far. But as I get older the thought
of simply turning a handle instead of pulling & grunting, etc.
appeals.

Doc


#10

Helen,

A draw bench is only a luxury until you have one. Mine is a boat
trailer winch and a bit of lumber, about 3 feet long. It lives
hanging from the rafters and when needed is clamped in the vice. No
expensive draw tongs, just a hardware store common slip joint pair
of pliers with a steel ring over the handles. Cheap (mainly scrounge
parts, decorative paint the greatest expense :-), and it doesn’t
take up space. Making big heavy wall tube is not only possible now
but fun.

Jeff


#11

Jeff,

Mine is a boat trailer winch and a bit of lumber, about 3 feet
long. 

Where does one find a boat trailer winch? A boat supply place or a
truck supply place or yet somewhere else? That really sounds
interesting. I had seen instructions on how to make on years ago &
now I’m not sure where they are, cost about $50 he said. This sounds
like it may be even easier since it’s something that can hang up out
of the way when not being used. Any more on it would be
appreciated. Thanks!

Lisa
Designs by Lisa Gallagher
www.lisagallagher.com


#12
Where does one find a boat trailer winch?

Lisa, you can check out Boat US, The Bass pro shop, your local boat
dealer or Academy if you have one. Sears may even have the item. I
took mine off my boat trailer and replaced it with a new larger model
that I bought at a local boat dealer… they should be easy to find.

Frank Goss


#13

Lisa,

Boat supply places cater to an exclusive market and charge
accordingly, probably worse than jewellery tool places.

Harbourfreight.com # 30905 looks like mine for $20. A decent chain
hardware store could order one, my local True Value has a stack of
catalogues over a foot high. They will order even stuff they didn’t
know existed provided that I can prove that it does.

Pictures of my bench at

http://www.ganoksin.com/ftp/drawBench.jpg
http://www.ganoksin.com/ftp/DBstored.jpg

Regular fir 2x4s, the ‘ears’ are oak screwed and glued. In hindsight
I should have imbedded a small rare earth magnet in each to hold
steel draw plates. Someday.

Any questions, just ask.

Jeff
Demand Designs
Analog/Digital Modelling & Goldsmithing
http://www.gmavt.net/~jdemand