Adding detail to a sheet metal object.
by Gene Olson
design ideas
scaling to fit
transferring your design to the tin
forming - repoussé and chasing
piercing - punch, chisel, and saw
appliqué - rivet, solder, glue
finishing - paints and patinas
I have several books here on tin and copper sheet work. They show various ways one could make a little metal box
and while it looks simple enough, making parts for a tight fit is quite a challenge. Once one gets the hard part done
one tends to get timid, "Oh my! If I mess up decorating this, I'll have to start all over. . . Oh dear, what if . . ." Thus
this project, practicing the fun part so when you go to decorate that tough to make part, you can approach it with
confidence. (The hard part may be finding someone to eat the candy.) There are a lot of ways that you can add design
and detail to a sheet metal piece such as piercing, forming, adding stuff, finishing and sealing , or combinations of all
of them . . . In this article we hope to give you a primer on these, something to get you started. Once you start, where
you go is your adventure.
What should I do?
What should I do?
What should I do? . . .
Stop worrying and get started on something, anything.
There was a study done once at an art school, half the class
was given the word, "You will be graded on the quantity of
work you turn in" and the other half was told, "You may turn
in as much or as little work as you wish, but you will be
graded on the quality of the work produced" In the end, it
was found that those who made the most work did the best
work. High concept without understanding of craft, without
practice, realization of success and failure, just didn't make very
much good art. Another part of this is, mistakes . . . we all make
them. It is how we recover from them, capitalize on them, reinvent them that spells the
difference between success and failure.
And failure? not here, we are all learning. This is still just an Altoids box that was headed
for the bin in the first place. It just took a side trip while you beat the heck out of it. Pick
up another one, and begin again.
Design Ideas:
Drawing your own or finding something, the important thing is to get started.
Practice is what will make your own design sing once you find it, so it doesn't really
matter what you start with. You will change it as you go anyway and make it your
own.
At this point pick something simple, draw a simple flower or maybe a single letter for a
monogram (here are three alphabets that you could use.) If you have a computer, there
are probably dozens of workable images in your clip art library. Go ahead and use them.
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The grid method.
Tools and Techniques:
Tools need not be expensive or fancy, a file, a
funky old screwdriver, a nail, a spoon, a piece of
2x4, These can get you started. And since the
material is relatively soft tools don't have to be the
best tool steel to give good service. (Making real
nice tools is a satisfying pursuit in it's own right,
and I recommend it, but for now let's get started)
Tool Lesson # 1 - Wear ear Plugs - Pounding on
metal makes an unholy racket. Wear ear
protection. Hearing loss is a real pain
Tool Lesson # 2 - Wear eye protection, steel chips
off tools or chemical burns are no fun and can put a
real crimp in your style.
forming - repoussé and chasing
(Gargle and then take that R from the gargle and
say) Ray, add Poose (rhymes with goose) add Eh?
(Kind of like a soft cough) now say it faster, Ray
Poose eh? now say it like you don't really care,
that's pretty good, almost French, and French for
pushed from behind. Chasing is similar, but it is
done from the front, and usually in finer detail.
In either case, your tools are rounded, dull. They
are not chisels, they are like tiny hammers. The
object is to move the metal from where it is to
where you want it. That is much the same as in
most any forging operation.
Forming sheet metal designs.
Repoussé and chasing are about stretching and
folding metal into a design. Two other words
used when describing this sort of work are
sinking and raising, sinking is stretching the
metal out like a balloon, raising is leaving the
center of an area untouched and then pounding
the edges in, "raising" them up (even though the
process is usually done by "lowering" them
below the level of the sheet) In blacksmithing
terms sinking is like drawing out, it thins and
stretches the metal; raising is like upsetting, it
shrinks the surface area and thickens the metal.
The terms sinking and raising are generally used
to describe processes used in forming objects
while repoussé and chasing usually have to do
with the final detailing of those objects. Sinking
and raising happens on very small local scales
as you chase or repousage an object. It is
sometimes useful to think about whether you need to stretch or compress the metal at a point to get some shape. All
of these processes are about forming the metal bending it or squeezing it at one point so it moves relative to some
other part. When one forms sheet metal or any metal for that matter, force is applied in one spot and the work is
supported in another so that the metal is moved away from the force point relative to the support point. Sinking and
raising are often done over air. The workpiece is supported at the edges or edge and driven down through the air
relative to the support point. Repoussé and chasing differ from this in that the support is usually a very very thick fluid
mix. Support is somewhat hydraulic, kind of like a waterbed. You push down in one spot and it pushes back some all
around. From
another per-spective, when you
push down in one
spot, the innate
strength of the
metal drags the
adjoining areas with
and the backing
material pitch or
other moves there
too, a steel stake or
die would not have
moved. Clay gives
the least support,
pitch gives much
more, lead or tin
gives even more.
Pitch is real useful
because it can be
stiff or soft as you
need it by adding a
little heat.
Clay will give you a
loose amorphous
edge, warm soft
pitch a harder edge
and cold hard pitch a much harder edge, lead or tin
backing probably providing the tightest radii and edges.
All of this is useful, to every thing there is a season and
a purpose, so says the old song. Initial work is best done
over something soft like clay or beaten in over a wood
block. You want those loose amorphous edges. You do
not want to define something early on. If you make a
couple tight lines, stress collects in corners, quite literally.
It is like a pry bar in a crack. It doesn't seem like you are
doing anything, but when you work an inch away on
some easy curve, the gentle taps out there are multiplied
many fold as they are transmitted to the area by the
sharp bend. Eventually it will probably crack there. Now,
maybe you wanted it to crack, but if you don't, be aware.
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![]() A couple of pitch tips: I have been using the Red German pitch for several years now (ever since Allcraft started to import it from Europe) It is, as good as the Northwest pitch, doesn't smoke when heated and melts at a relatively low temperature. If you are careful not to overheat it, the pitch will last for years. Coat the back of your metal with mineral oil for easy removal. You can also use a regular chop stick (learned this from Anne Hollerback in Massachusetts). Always use a soft brushy flame, and be especially careful with the acetylene torch. A heat gun will work, as well. Valentin Yotkov
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![]() piercing and cutting - punch, chisel, and saw |
Applied design pieces are an excellent way of using
that one little part of your last attempt that worked.
Snag that tin out of the trash, cut out the good part and
solder it on as part of a new composition. This can be
especially fun, as you get to move an almost finished
piece around and determine where it might look best.

finishing - paints, plate, and patinas
Beauty is only skin deep, . . . or so they say. Paints,
colored bits of material in some sort of fluid medium
which carries and as it dries binds the color in place.
Plating, chemically depositing a metal on the surface.
Patinas, corrosion and abrasion - chemical and
physical colors and textures using the usually using the base metal and it's variously colored compounds, these colors
are then usually fixed in place and color with a coating of some kind. Finishes usually have two major hurdles other
than looking right, the first one is getting it to stick the second is getting it to last.
In all processes getting the surface clean is extremely important. Paints, enamels, solders all require a clean surface.
If you decide to re-tin the cover after annealing and forming, it needs to be cleaned with flux and the solder brushed
on over the fluxed surface to get it to stick. For finishing there are chemical blackening and plating options as well.
I used a copper plating solution called Copper Coat on the first one I tried. Patinas are often sealed with wax or laquer.
Sources for some materials and tools are listed at the end of this article.

I am sure 330 inventive, creative members are going to come up with some novel approaches.
I'm looking forward to seeing all your inventions and artistry at the conference.
Gene Olson
Resources:
Chasers pitch - Here in Minnesota, Corky Kittleson and I (Gene Olson) have several lbs on hand from Northwest
Pitchworks. With freight the cost from Bellingham is about $9.25/lb. If you want a few oz. to try give Corky or I a call.
| Kittelson, Cordell
300 East 4th St E Apt 201 St Paul, MN 55101-1441 Home phone: 651-848-0759 Work phone: 651-773-4662 email: corkyk@isd.net |
Olson, Gene
8600 O'Dean Ave NE Elk River, MN 55330-7167 Home phone: 763-441-1563 Fax number: 763-441-5846 email: gene@mettleworks.com |
If you want pounds of it, you can get it from these places.
| Northwest Pitchworks
1317 Roland Street Bellingham WA 98226 306-715-1772 http://www.northwestpitchworks.com |
Red German Pitch from
Allcraft NY NY Tel: 212-279 7077; 1-800-645 7124 |
Copper Plating solution for Tin, iron, lead, brass called COPPER COAT
| Modern Options
888 Brannan St. San Francisco, CA 94103 |
Note: this is simply a mixture of copper sulphate
(sometimes used as an herbicide to kill aquatic plants)
and sulphuric acid (acid drain cleaner).
Acid Handling Safety rules apply. Wear goggles & gloves, add acid to water not the other way around. |
Tools such as the jewelers saw: Rio Grande 1 800 545-6566
Our own Fiorini and Skiles make repoussé tools 507-643-7946
You can make your own, or convince your favorite smith to help.
Good luck to all!
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