Problem with new Durston Rolling Mill

After great deliberation with sales people, I bought my first Durston
rolling mill, an 80 mm flat mill. I am a beginning metalsmithing
student and I communicated my needs, mostly to flatten wire and make
impressions with brass etched plates on annealed silver that is 22-26
gauge. To say I am disappointed is an understatement. I cannot make a
decent impression much less flatten anything larger than a piece of
24 gauge wire. Is this normal? I wrote to Durston and received a one
sentence reply saying I should purchase another mill with reduction
gear. So much for customer service. When I called Otto Frei, I was
told that I could not roll anything over 3 mm when the specs on their
website state that 6 mm is appropriate. Any ideas or suggestions?

You will get better results with a mill with reduction. The DRM F130
R is a good choice. The 5-1 reduction will allow you to make a
better impression.

Matthew Durston

I cannot make a decent impression much less flatten anything larger
than a piece of 24 gauge wire. Is this normal? 

Can you elaborate “cannot”. What is that stops you?

Leonid Surpin

Betsy,

The only rolling mills I have used which did NOT have reduction gears
were brutally difficult to use. You are right, rolling a sheet of any
width at all requires real strength and lots of leverage to force
anything through the rollers. My advice would be to exchange the flat
mill you have for one with reduction gears ( 6 to 1 ). That will
really help with the effort required, and make the rolling
manageable for you.

I’d also highly recommend a combination mill, which has both grooves
and flat rollers. With only flat rollers, you will be really limited
in what you can do with your mill. The grooves allow you to make
wire stock, as well as narrowing sheet or wire stock. Step tapering
for wire drawing or forging is another handy thing the grooves can do
for you. I would also highly recommend removable side rollers, which
will allow you to make custom shapes, like half-round wire, or any
other roller shapes you care to buy or have machined.

It’s all about versatility. Your mill ought to have features that
will let you do more with it as your needs develop. A rolling mill
with only flat rollers will not make everything you might want it to,
so it’s well worth it to have a mill which has the extra capability
you may very well want later.

Jay Whaley

I cannot make a decent impression much less flatten anything larger
than a piece of 24 gauge wire. Is this normal? 

No. But I doubt it’s a problem with the mill itself. Rather, I
expect you’re trying to use it improperly. Not sure how, but 24 guage
wire is so small you can almost reduce it by hand with just a
burnisher, much less a rolling mill. If, for example, you try to feed
anything into a mill who’s rollers are completely closed, you
probably won’t suceed, as the rolls need to be far enough apart that
they can “grab” the metal. Same thing with taking too much of a
“bite” on wider sheet. The rolls not only have to be able to grab the
metal without slipping, but then you have to be able to physically
move the crank. On a mill without reduction gears, this may be
limited by your own strength long before it’s limited by the mill
itself, thus the suggestion for a mill with reduction gears.

I wrote to Durston and received a one sentence reply saying I
should purchase another mill with reduction gear. So much for
customer service. 

What else would you have them say? Their answer sounds to me like
the truth. It’s unlikely a problem with the mill, as there isn’t some
mysterious hidden manufacturing or design fault that might lessen the
mills capability, unless such a fault shows up by the mill actually
breaking. Most likely, you’re trying to do things either improperly,
or things unsuited to that size and type of mill. The answer would
either be to get a mill better suited to your task (bigger, or as
they suggest, with reduction gears), or to get some help from
someone more experienced in this use, to show you how to better do
it. For the record, roll printing (what you’re doing in trying to get
an impression from a brass sheet on sterling) can take a lot of force
to do well, as you’re needing the mill to push the metal a lot in a
single pass, rather than a little at a time, as is normal with just
thinning a piece of sheet metal. Also, your silver sheet, if it’s as
thin as 26 guage, may simply not be able to take much of an
impression. The silver needs to be thick enough so the needed depth
of impression is available in the thickness of the sheet. 25 guage
may simply be too thin for simple roll printing. Embossing, where the
metal isnt’ thinned, but pushed into a design by a softer backup
sheet, works with thin metal, but then you’re rolling a sandwich of
at least three layers of material, and then you may be running up
against capacity limits on thickness. But 22 guage should have worked
for ordinary roll printing.

When I called Otto Frei, I was told that I could not roll anything
over 3 mm when the specs on their website state that 6 mm is
appropriate. Any ideas or suggestions? 

6 mm is a very wide space for a small mill. Open the rolls too far,
and the gear teeth driving the rolls no longer engage. That factor is
what limits thickness. A mill with a 3mm limit, however, shouldn’t
stop you. That’s a very thick piece of metal in the first place, and
other than a poured ingot you normally don’t need more than that. But
as I said, the limit to thickness isn’t the rolls. It’s how far apart
they can be before the gear teeth no longer properly engage. If your
stack of silver and brass is too thick, you may have a problem. The
answer would be reducing something, such as the thickness of your
brass sheets.

Again, just for the record, the Durston mills are among the finest
in the world. It’s unlikely that you’ve a problem with your mill’s
quality or manufacturing or something. Most likely, you’re either
using it incorrectly, which could be fixed by someone with more
experience showing you how to use it, or you’ve chosen the wrong mill
for what you need to do, which would be fixed by returning your mill
and getting one better suited. Reduction gears might well be what
you need if you’re doing it right and it’s not working. One other
comment. While the full width of the rolls is available for normal
rolling of sheet metal thinner, where you can use multiple passes
thinning a little at a time, for roll printing/embossing, where you
may need to take a deep bite all at once, trying to use the full
width of the rolls, even with fully annealed metal, may be trying to
get too much from the mill for it’s size. Likely, the length of the
handle may simply not be designed to give you that much leveridge
over a small mill. A larger mill, even direct drive, would be easier,
and reduction gears will pretty much fix that problem too.

Peter

So who did you buy from, did you contact them? Who ever you talked
to at Otto Frei was mistaken the Durston 80mm mini mill can handle
6mm sheet which you can see if you go to the Durston website. The
problem as you have found out is there is no gear reduction on the
mini mill so you need to be strong enough to roll the items you want
to work on. For simple small reductions in thickness of small pieces
this is a great mill. But for larger sheet or roll printing you
better be very strong to operate it. While you may have an issue with
the sales person who sold you the mill not understanding what you
wanted to do you must remember these folks for the most part are not
jewelers or metalsmiths so they may not be able to advise you as to
the suitability of a particular tool for your use. I would suggest
you contact the vendor who sold you the mill and see if you can
exchange it. As for Durston’s response what did you expect them to
do? You purchased a mill that is not suitable for your intended use,
they told you what you needed to do to correct the situation.

James Binnion
James Binnion Metal Arts

On the advice of Peter Rowe, a fellow metal worker, I had a moment
to join the ganoksin forum. So this is my first post.

Can you detail the thickness in thous of an inch of the silver? you
cant emboss?

also the specification? ie standard sterling? or fine? Ill try and
help you to do what you want.

so did you actually get to try the Durston in a jewellery machinery
sale outlet? Most places like that will let you try out what you
have in mind as they might learn something too!!. If not. Then you
need to find a silversmith that has a no of mills who will let you
try out your ideas. If you were nearer you could come here where Ive
a durston, (powered) plus lots of other heavy kit, like coining
presses and embossing drop hammers.

Before you give up with the mill you have, the first thing to try is
some lead sheet, then some annealed copper then some 999 dead soft
aluminium. this will give you a yard stick by which to judge wether
you need a bigger mill or a change of technique.

On the advice of Peter Rowe, a fellow metal worker, I had a moment
to join the ganoksin forum. So this is my first post. 

Hey Ted. Welcome to Orchid. "bout time. How many years has it been
since I first suggested Orchid to you? I assume this means you’ve
finally managed to get better internet access to your corner of the
world? I have a dim memory of you saying that was the problem…

cheers
Peter

I was in the process of writing a defense for Durston, as I think
they make magnificent rolling mills, and are one of the last UK
engineering companies who can export steel tools! But, having checked
out their website, I see that the 6mm figure is used on all of the
small hand-powered mills - although ours is 15 years old, it looks
about the same as the modern ones, and there is no chance in hell
that you can get a 6mm sheet through it - the gears simply will not
mesh once you get past 5mm (maybe less), although the height of the
top roller can be raised well beyond that point. Surprised by this
discrepancy, as Durston are such a great company.

Jamie Hall
rhttp://primitive.ganoksin.com

The tech guy at Otto Frei told me that he did not think it would
handle more than 3 mm. This is why I returned it!

Hi Betsy,

There have been a few replies to your call for help, none which I
thought were really helpful.

I have given it some more thought, along the lines of, what would i
do if i was in your position and wanted to emboss metal? with a
rolling mill.

Well, roll embossing/ coining can be done but you need the right
tool for the job which regrettably you dont have…

As you havnt mentioned

  1. the thickness in thous

  2. the thickness of the brass etched plate

and the size, width and length, its more difficult to give a precise
answer.

Now Ive been minting and embossing for at least 20 yrs with tool
steel dies and the right machinery so know what you need to do. When
rolling metal it tends to curve up, ie not come out straight, so a
mill isnt the best way to to do the job apart from other technical
issues…

What you need is in fact an engineering solution to what put simply
is metal bending.

This doesnt need anything like the tonnage, yes tons!! of energy to
make the metal flow like in coining.

You need to make 2 brass plates, one the negative which you have
already AND a positive of the design both the same size, at least
3/16th in thick.

Then you put your silver between the two and squeeze then together,
evenly all over,ie a 1/2in steel plate ontop and below.

The easiest way to do this s with a car repair shop hydraulic press.
Youll need to ask a local car repair shop to do it for you, your a
girl!! so smile!! and they will probably do it for free!! The press
needs to be over 10 tons of load ability.

You then takethe sandwich out of the hyd press, have a look and see
how it has come out.

It depends on all sorts of things like depth of embossing, clearance
between the etching of the 2 brass plates, there needs to be enough
space for the silver toNOT be sheared by the brass etched edges. Hope
you follow.

Also how many of the silver items you plan to produce for the
product,10? 100? 1000?

this is in addition to your artistic design, pricing marketing etc in
making such a product.

Thats why Ive always advised young folk to work in a manufacturing
silversmiths workshop. Theres no substitute for learning from the
masters.

Now getting back to your mill, IF you explaind in detail what you
wanted to do and your mill supplier said it would do the job, it
obviously wont so you have a good case to return it for a refund. you
need to give that a try.

A mill could do it but it would need to be much bigger with rolls
reduced in size to have enough clearance for the 2 brass or steel
plates as well as the silver and still have the gears mesh properly.
In other words get Durston to make you another set of rolls to do
specifically what you want. They will of course be useless for
normal metal rolling.

More on powered rolling another time.

Let us know how you get on.

Ted.
in
Dorset
UK…

Thank you, Ted, for your thoughtful reply. I have appreciated
everyone’s opinion and am now waiting for the seller to examine the
rolling mill and share their assessment. My Durston replaced an
inexpensive rolling mill from India (I believe it was called an
Economy Rolling Mill) that worked quite well! So sorry I sold it now.

All the best,
Betsy