Repousse'

Sheet Metal Relief or Sculpture

"Raising" is a technical term applied to making bowls, helmets and various hollow vessles by hammering. The material is actualy made thicker at the edge shrinking the perimeter and making a bowl shape. Raising is done with a variety of hammers while working over a "stake" or special anvil. Raising is often started with a simple sinking operation but not so much that it thins the sheet apprecicably.

"Repousse'" is the making of shallow bas-relief sculpture on a surface. This is done by sinking (stretching) the metal down into a mold, shotbag (or sandbag) or a soft supporting matrix called pitch (mixture of wax, tar and filler).

Tools needed depend on the type work you are doing. They can vary from common tools from a hardware store to hand made specialty tools. Most artists end up making many of their own. I've used nut picks and broken screw drivers that I reground the end to shape. Repousse and raising hammers are often the same tools.

Both of these proceses can vary from thin stuff done entirely by hand with small tools up to heavy plate worked with power tools.
- guru - Monday, 10/01/01 19:10:30 GMT

Steps in raising a vessel. Raising/repousse' hammer in use.
Decorative and Sculptural Ironwork, Dona Z. Meilach
Hello fellow Smith,

I have been asked to bid on a fairly large weather-vain to be done in copper. The subject matter is a horseman and his 4 hounds. It is to be done in a repousse style. Could you recommend a good how to book or video on this technique. Thank you,
Tomas Fernandez - Tuesday, 03/21/00 15:06:51 GMT


REPOUSSE': Thomas, There are several methods of producing repousse'. The classic method is to mold or pour a pitch backing onto the metal and hammer the metal in to the pitch which displaces while supporting the surrounding metal. The pitch is sometimes made by the sculptor or purchased from art suppliers. Each artist has his prefered material or recipe. Sometimes the mix has sand added to it for added stifness and volume. Modern pitch is usualy a wax based product and comes in various hardnesses. The pitch may have to be removed and repoured if the work needs to be annealed during the process. In some cases and with rapidly work hardening materials such as brass this may be two or three times.

Another common method is to use a sand bag. A Soft leather bag is the classic method. The last repousse' I did was a copper crown for my daughter's Latin dinner. I made the sand bag by partialy filling a heavy duty zip-lock bag with sand and folding over the extra "flap". This was sewn inside a piece of cut of leg from a pair of blue-jeans.

The copper was formed by working against the sand bag, pressing the smooth butt of my small Buck folder (pocked knife) into the metal and "chasing" the design. The more times it was chased the deeper the depression. Sharper portions were chased with a graphite pencil. No hammering was required. Copper is almost as maleable as gold.

Production weather vanes were produced in cast iron molds. Wood can also be used for limited runs. The trick is that you have to produce a left AND a right hand form (mirror images). This can be expensive for a one-off piece but in the long run may produce the best results. Both sides will be close enough to the same shape to solder or braze together without difficulty.

To make shallow low definition wood molds quickly, you need to layout your work to be cut in 1/8" (3 mm) or 1/4" (6mm) sections as a "topographic" map. For a two inch (50 mm) thick double sided design you will need 8 (or 4) maps. Stack and cut two layers of masonite (hardboard) Laminate these pieces in lefts and rights on a piece of 3/4" (18mm) plywood or several layers of thinner material also laminated.

After the glue is dry rough sand the form to shape using a dish sander on a drill or hand grinder to remove 85-95% of the "steps" in your form. You may also want to carve extra detail with a die grinder but remember this is only a rough form. DO NOT BREATHE the dust from the masonite.

Once the forms are finished take annealed sheet copper and start pressing it into the molds. Use a large well radiused rubber or wood mallet. Use wooden forming tools made from dowels or a broom handle (they come with one nice round end). Keep pressing and pushing the copper into the form until you are satisfied. For this project you may need to anneal only once if there is not too sever of depth changes in the design. I would use hard wood tools as much as possible and only use metal chasing tools for the fine detail. Both should have smooth rounded edges. A dull screw driver with the blade ground and polished to a nice oviod shape is an excelent tool for chasing details. The metal sculptors tools sold for working clay are also good shapes.

Once finished with the wooden forms you can return to the classic method using a backing OR a sand bag depending on the detail desired. I would probably be prepared to use both. Remember, the pitch can be used on either side depending on which way you need to move the metal. IF you need to produce high sharp relief then anneal after rough forming into the wooden forms. Attempting to stretch the metal in one step may result in tears in the metal.

When you are done with the forms, sand the edges and varnish the whole. You then have a great mantle piece or wall hanging to keep as a reminder of the job. If the customer wants them be sure to let them know the form is more expensive than the copper vane!

Chris Worsley says on ArtMetal-
One good source of information on this subject is the book Metal Techniques For Craftsmen by Oppi Untracht. ISBN: 0-385-03027-4
- guru - Tuesday, 03/21/00 20:00:46 GMT
Gurus, finally got around to checking and you are back, man am I glad, a truly fine service. I have a question on forging sheet/plate ala repousse'/chasing/engraving/bouching(sp). How does one back up hot metal, can't use pitch/sand bag, lead might(?)be dangerous!. Am I correct that I should make larger 'graver' type tools as well as various oversized stamp type tools. I've been fooling around with this for a couple of weeks, and its obvious that I need guidance oh wise and all knowing gurus...thanks
Tim - Tuesday, 07/25/00 04:20:18 GMT


Hot repousse' Tim there was a demo of this at the ABANA conference. I've got some photos but not yet posted them.

The steel plate was supported above a heavy bench (a weld platten) on spacers made of heavy square structural tubing. It was held down by flat bar and heavy bent dogs.

The plate was heated localy with a rose bud heating tip and the metal shaping done with a hand held air hammer.

It was the NOISIEST thing I have ever heard and I have been in some places that had REAL noise (and made quite a bit of my own). Multiple levels of hearing protection are required and you better not have neighbors within maybe 500 feet!

Hot work can also be supported by clean dry sand in box setting on a similar heavy bench. It will cool the metal faster than being supported in air but the process will not be as noisy. I would recommend preheating the sand. A high temperature silica sand like used in foundry work would be best.

For detail work a fellow at the conference had hand held air hammer supported in a deep "C" frame. The body of the hammer sliped into a close fitting bushing. The "chisle" point worked opposite a mating or female part. The air was controled by a foot valve. Weights were added/removed at the top of the hammer as the work required. The method could be used for hot work.

abana2k/abana08.jpg abana2k/abana09.jpg abana2k/abana10.jpg


I've also known smiths to work plate under the power hammer. Deep throat hammers such as the Kaynes "BIG BLUE" or the old Bradley helve hammers are good for this.
- guru - Tuesday, 07/25/00 12:56:06 GMT

Hot repousse'- I find the packed sand in my drive-way to be the perfect backing.
John Careatti - Tuesday, 07/25/00 22:25:31 GMT
Greetings from a residential contractor with artistic yearnings,

I would like to make a hammered brass sheet exterior accent trim accessory to incorporate into a cedar shake job - a triangular 36" x 20" sunburst.

questions:
1. material source and type (soft brass?)
2. methods resources, sites & books etc.

gary m - Tuesday, 05/28/02 12:44:28 GMT


Sunburst: Gary, the type of work you are describing is called "repousse'". This is sculpture similar to bas-relief in sheet metal.

Our Online Metals store sells the brass you need. I would recommend 16 to 18 ga. for the size work you describe.

Step one is to anneal the sheet by heating it to a low red (just barely visible) in VERY low light and quenching it. Quenching is not always necessary (but recommended) and you may anneal the portions to be worked as needed.

The plate is then backed up by "pitch". This can be made by melting roofing tar and mixing in about an equal part of fine sand or a filler like plaster of Paris. The heavier the metal the coarser the fill. Commercial pitch is also available from art supply houses and is often a wax/tar and filler mixture that comes in varying densities.

To backup the plate you melt the pitch and pour a layer about 1" (25mm) to 1-1/2" (38mm) thick. You can make a simple wood frame mold to hold the melted until it has cooled.

Draw your design on the surface of the metal with pencil or marker.

Then using repousse' hammers, punches and (dull or rounded) chisles, you work the shape in reverse. Repousse' hammers have special shaped heads and piens. Some types are sold as auto-body hammers, others are available from specialty shops . Kayne and Son carry several.

You can also use ball pien hammers for a limited amount of work and many smiths modify ball piens by reforging them to specialized shapes.

Many of the other small tools you need are simply made from common punches and chisles. The ends should be radiused and ground or polished smooth. You want no sharp corners that will cut or tear the metal or rough surfaces that leave marks. This also applies to your hammers.

For deep relief the metal may need to be annealed several times as it work hardens from the hammering and stretching. To do this you strip off the pitch, anneal the metal as above, then repour the pitch.

Pitch is also removed and repoured if the back gets too out of shape to support the work. Occasionaly artists simply level it with heat from a propane torch.

I suspect that for what you want to do you will not need to anneal a second time. However, it is often useful to repour the pitch on the reverse (back) side once the shape is well defined in order to use chisles and such to sharpen the definition of inside corners. You must be very careful doing this to prevent tearing the metal or punching a hole in it.

See our archives or search on pitch, repose', repouse or repousse, March 2000 week 3 lists a book and alternative methods.

Pete F. Please let me know your recipe for pitch (I think it was yours). I've searched the archives. . but "pitch" is a bad keyword to search on. I THINK I have it right (above).

- guru - Tuesday, 05/28/02 16:03:15 GMT
PITCH RECIPES:

1. 6 parts chaser's pitch, 8 parts plaster of Paris or brick dust, 1 part linseed oil or tallow. Source: Metalworking Techniques for Craftsmen by Oppi Untracht.

2. 4 parts roofing tar (the kind roofers melt in tar kettles), 3 parts pumice powder, 1 part turpentine, 1 part linseed oil. Melt tar in pan, stir in turps, add pumice. Let a small amount cool and adjust amount of linseed oil to get desired consistency. Source: My own recipe.

3. Equal parts of beeswax and plaster of Paris. This is good for very thin, fully annealed non-ferrous metal worked shallowly. Again, my recipe.

When mixing any of the recipes for pitch, remember that some or all of the materials may be flammable and take appropriate precautions with regard to open flame, etc. It's a good idea to keep in mind that hot pitch sticks to you and keeps on burning much longer than is bearable, too.

For steel or relatively thick (greater than 16 ga.) non-ferrous metal, you want the pitch to be stiffer than you would for softer or thinner metals. The stiffer the pitch is, the sharper the detail you can get, because it doesn't distribute the force of the punch as much as softer pitch does. For preliminary bumping of the gross forms, I use a softer pitch, and then switch to a stiffer consistency for detail work or chasing from the front. Sometimes, depending on the nature of the project, the initial bumping can be done over a sand or shotbag, or over a depression in a wood block or stump. If it is important that the perimeter of the piece be very exact, it's sometimes easiest to leave it large and cut it to the final contour after all the repousse'/chasing is done.

Remember that whatever surface is present on the end of the punch or hammer is going to be impressed into your work. If you want a smooth surface, polish your tools to a shine. Conversely, you can texture areas by using tools with pitted, grooved or checkered faces. Sharp tools run the risk of cutting the metal, so it's a good idea to radius the corners of tools. Oppi Untracht's book mentioned above has some good and useful information on the techniques involved, as do many other jewelry making books.

vicopper - Wednesday, 05/29/02 05:48:32 GMT

A Discussion on Tools


How thin, or how much curve should be on butcher's? I am attempting to learn repousse and am grinding on material to make matched sets of Butcher's first & second pass. But I don't know how the ends should be shaped.

Tim - Tuesday, 11/04/03 12:39:21 EST

Tim,I thought butchers were big ol' things for starting shoulders on hot work (?) Please advise.

Frank Turley - Tuesday, 11/04/03 14:52:50 EST

Mr. Turley, George Dixon, publisher(author) of "Traditional Metalsmith" illustrates using butchers or something similar to this to do repousse work. The front page of his magazine web site has one drawing showing it "artist-blacksmith.org" directly below the center menu. I may be confusing the name with another repousse tool. I have these tools forged out of air hardening tools steel, and just trying to get the angles close to right.

Tim - Tuesday, 11/04/03 15:09:19 EST

The tool I think you are reffering to looks like it's being used in "setting down" in heavy plate. Regardless, repousse tools can be any shape you want, it's just the reverse of the shape you are trying to achive. Too sharp of an edge will cut the steel though.

- grant - Tuesday, 11/04/03 16:37:17 EST

Repousse' Tools: I have a nice article on dressing these that was reproduced in our local group's newsletter and copied from ANOTHER groups letter. . . But I couldn't find the author to get permission to use the article and can't place my hands on it immediately. It seems to me that the rounder the better. . . But it also seemed that there was some tricks to it. I found the images from the old Koka Metalworks site and see that the tools are smaller on the struck end than the working end. Bill made many shapes and had many drawings but they are not detailed. Most showed the crossections and the general end shape.

- guru - Tuesday, 11/04/03 17:51:44 EST

Repousse' tools:

The book was listed in a recent issue of The Hammer's Blow, and is titled Moving Metal: The Art of Chasing and Repousse' by Adolph Steines. It is available from Blue Moon Press (866) 627-6922. A really great book on the subject.

Repousse' punches are generally used from the back of the metal to move the metal out and, as such, are very generously rounded off so as not to tear the metal. The "butcher" tool is also called a "liner" or "setting down" tool and used for the chasing work whiuch is dome from the front. For initial movement of the metal, a bit rounder profile is preferred, so that lthe metal can be moved a good distance without tearing or thinning too much. After the detail is established, then you can go to a much sharper tool to set down very tight cornered areas and contours. Naturally, all this involves annealing between workings so you don't crack something. If the piece is going to be subjected to any level of physical strain after completion, avoid extremely sharp corners that can be stress risers and end up cracking in use. In the final analysis, the profile of your tools will be controlled as much by your own style of working as it will by any preset notion of what someone else says is right. Make them, try them out, and see what you would like to be fdifferent and then make a new one.

Please note that I said "make a new one", NOT remake the old one. I have found that some of my favorite chasing tools now are ones that I made years ago and thought weren't right at the time but didn't change. BTW, the reason for making the struck end smallr than the working end is twofold. One, it concentrates the hammer blow down the center of the tool, the same way it does on a punch or when upsetting. Two, there is more hammer control when you don't have to deal with off-angle blows striking a "corner" of the tool and causing the tool to skate away.

vicopper - Tuesday, 11/04/03 18:38:28 EST

On repousse Has anyone ever heard of a really strong air chisel for steel repousse? I tried with my weenie Sears air chisel and no go cold and annealed. I made a few tools and none seem to move 16 gage steel except when it's screaming hot. I wonder if 16 ga sheet is too thick... - andrew - Tuesday, 11/04/03 19:21:38 EST

Air chisel:

Andrew, there are a number of air tools made that will do the job. I have a Chinese knock-off of a Rockwell weld chipping chisel that does pretty weell once you make new chisels for it. The ones that come with it are too soft for anything but repousse', so I make my won cutting chisels from S-7 or similar steel and heat treat them for the purpose. Check industrial suppliers for the tools, asking for weld chippers and the like. For 16 gauge, which is NOT too heavy, you need a tool that has some mass to it to move the metal cold. You also need to have the metal backed up with the right substance, like lead. Working on wood is way too "bouncy" and wastes the energy of the blow. Lead or good pitch will absorb the movement but not let the metal bounce around.

Another factor that will make a huge difference is the steel that you're using. Common A-36 sheet is likely to be too hard to be nice to work, even after careful annealing. I suggest you get some 1008 steel or 1018, and try that. The best thing is pure iron, but that is gonna really cost you since it is no longer being sold in the US. You can still get it in England, if you're willing to pay the tariff to ship it. I found an old piece of pretty good quality wrought iron the other day and tried it. The difference was amazing. That stuff moved like butter compared to A-36. vicopper - Tuesday, 11/04/03 19:47:51 EST

Power Repousse' Andrew, I have seen is done a variety of ways. We saw several demonstrations at the Flagstaff ABANA conference. Some (chasing mostly) was done with a small modular hammer in a C frame and some was done on heavy plate using a large hand held hammer. See the NEWS vol 21 slideshow frames 8-9. The heavy plate was worked hot while supported between and clamped to two heavy bars. The noise was unbelievable. The C-frame machine has its power controlled by the weights stacked on the hammer (mass to resist the force). English wheels are also used when large contoured areas are involved.

First, everything in proportion. A small hammer will need tools with small ends to concentrate the available energy. It will also need to be used on thin plate. I have not tried my B&D hand held on plate but I know how hard it hits and it should work on plate up to 16ga as long as it has tools proportionate to its power. It also needs a good air supply. It outruns a 1 HP air compressor in a few seconds and it drew down a big 6HP fast enough that that it was constantly running. . . Try putting a pressure gauge on the tool end of the hose and watch while the tool runs. Line drop coupled with fall off before restart can drop that 100 PSI (700 kPa) working pressure to half. You can reduce line drop with a bigger or shorter hose. But the compressor capacity must be there.

Plate of all thickness needs to be annealed to start. Most repousse' artists are picky about the specific alloy because some plate is a lot tougher to work than others. Special plate made for deep drawing works mush better than common A-36 plate (which is what your 16ga many be). Deep draw plate is usualy delivered annealed and finished. European's prefer to use wrought or pure iron plate due to its softness.

How your plate is supported is critical. Repousse' artists are constantly testing different pitch recipes. For heavy work it is often sand filled. One fellow said that the packed gravel in his driveway was the best thing he had found for heavy plate. If you are using poured pitch it must be stripped and replaced as the work progresses.

Heavy plate is usualy worked hot. 16ga is right on the verge of being heavy plate and if a low grade IS heavy plate. Working hot avoids annealing but introduces the need for gloves, tongs and other hot work tools. A sand table can be used to good advantage but it must be supported like its an anvil. It can also be worked on heavy edge supports (but is very noisy). To finish heavy plate after working it free style you may want to use a pitch backing for that last pass.

If you use an air hammer on plate be sure to wear hearing protection.

Repousse and deep relief chasing are slow processes in steel. If you do not have the patience for it try copper.

- guru - Tuesday, 11/04/03 20:05:18 EST

Repousse'

Yes we agree on this Jock. I'm glad you mentioned the deep drawing plate, which I neglected. Also the tool to driver ratio, which is critical on smaller air tools for moving metal.

One other thing I neglected to mention is "complete" annealing. Too often, particularly on relatively thin materials, the usual method of annealing in vermiculite, perlite or ashes isn't adequate. On sheet in particular, there is such a high surface area to mass ratio that it is extremely difficult to keep the stock form losing heat too rapidly to anneal effectively. Usually, all that is achieved is not much more than normalizing.

To anneal sheet stock fully, it helps to heat up a chunk of really heavy (1 or 2" thick) plate as big as or bigger than the piece of thin plate you want to anneal. Also pre-heat your annealing medium by shoving a piece of healted stock into it an hour or so ahead of time. If you put the thick piece of stock in with the thin stock next to it, (or even better between two pieces of it), you will get the slow cooling needed to get complete annealing. Or use an annealing kiln with controlled temperature reduction. The point is, it must be SLOW cooling.

Personally, I do the roughing in hot, using a heavy asbestos glove on my left hand to hold the sheet tongs. Gets to be real fun when it slips out of the tongs, too. (grin) Protectivbe clothing is an absolute must when working sheet hot. Just the radiated heat can blister your face and arms. As for the noise, if you don't use the hearing protection that Jock recommended, you'll end up deaf like me.

vicopper - Tuesday, 11/04/03 21:24:04 EST

Low Carbon Steel


For repoussť and chasing Armco used to make zero carbon iron for enameling. Check it out.

Yeah Tim, I looked at Dixon's magazine. Schwarzkopf calls the "butcher" a "veiner", thinking about leaf veins. Same tool. There are similarities between metal chasing /stamping and leather tooling. In leather work, the butcher is a "beveler", but before using it, a swivel knife cut is made, and the beveler sets the damp leather to one side or the other of the cut.

The English language. We needed to borrow the French term, "repoussť", because it covers two processes. If we didn't have the term, we'd probably have to say "emboss" and "chase".

Jewelry catalogs and Untracht's book, "Metal Techniques for Craftsmen", show quite an array of repousse/chasing tools.

Frank Turley - Tuesday, 11/04/03 22:09:51 EST

Armco zero carbon: NOTE that Armco is now AKsteel (www.aksteel.com).

I had a fellow come to me a couple weeks ago looking for .005 or less carbon steel (pure iron) wire. He was told that they no longer made the low carbon steel in wire. According to their literature all they currently make is transformer plate in 24 thru 29 gauge. I have old catalogs that list round, square and rectangular coil wire in special electrical grades. It is no longer made.

They also make a deep drawing aluminium alloy steel (DS) with .06% carbon. This is a super ductile version of SAE 1006 but is far from zero carbon. This is also only available in plate (up to .35"). I suspect that the carbon adds strength that makes it draw and form better than the lower carbon silicon iron made for electrical purposes.

- guru - Tuesday, 11/04/03 23:43:53 EST

References and Links




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