Repoussé (pronounced Reh-Pew-Zay) literally translated, is the art of "raising", specifically in metal. Simply put, it's the art of creating a 3-dimensional art surface from a sheet of metal. The technique is thousands of years old and was heavily used by blacksmiths, armorers, jewelers, and others. Many of today's techniques for tooling leather are also similar. The same general principles apply to tool leather as well as to emboss metal. Repoussé is sometimes done without "chasing" but usually both are used in conjuction with one another to create an embossed design.
Repoussé is to work the back of the piece, so that from the front you have a raised design. Chasing is fundamentally the same, but instead you are working the front to create detail or depressions on the front surface.
The process generally works as follows: You have a sheet of metal, and by taking very smoothed punches and chisels (the tips are highly polished so as not to "cut" the metal, but instead to "push" it). You use a liner (small chisel like shape) to line the detail of your work. To absorb the shock of the process, the work piece is placed on a firm, but giving surface. Loosely referred to as a "chasing medium" or "chaser's pitch". Chaser's pitch is a substance made from tar, pitch, clay, sand, etc to create a firm yet viscous surface to strike against. For heavier work such as steel, lead or tin is generally used as a chasing medium. Here are some examples of repousse and chased work:
Taking a hammer and these smoothly polished punches/chisels you work the metal into the chasing medium, slowly raising the design from the sheet. The chasing medium serves two purposes simultaneously. First, it provides a firm surface to help support the non-raised areas and ensure the entire shock of the blow is focused on the area you are moving. Second, the chasing medium is soft enough to give directly beneath the struck area so the design is raised and you don't just bang it against another hard surface, thinning the work metal too much. This is one key area where chasing and repoussé differ from blacksmithing.
You want to continually anneal the work piece if it is made from a metal that will work harden. Many metals get more brittle as the molecules are compacted. Have you ever taken metal wire and bent it, then bent the same spot the other way, then again and again? Eventually it snaps. This is due to the "work hardening" that is happening at the bend point on the metal. Annealing loosens the molecules again and keeps the metal malleable and prevents it from becoming brittle and cracking while you're working. Materials like copper, brass and bronze work harden very quickly and so you must anneal quite often. Steel work hardens more slowly, but in general is harder to move due to its strength.
Once you've raised the surface, you flip the worked piece over and do the same thing from the front, making the lines sharper, or recessing areas that have unintentionally become raised (generally around the edges of the design you are trying to emboss).
That's repoussé in a nutshell, but words can never do as well as a short video. Here is a repoussé artist creating repousse onto a plate of sterling silver. You can see the general process in this short (roughly 7-minute) video. This is precisely the process I am using for my shield (and will be using for the armor for the Zelda costume). For the shield, the major differences are in the size and weight of the chisels I am using, the hammers I am using are heavier, and the chasing medium is not pitch (as in the video), but instead I am using pure tin (which is soft similar to lead, but less hazardous).
Take a look, this will help y'all understand what it is exactly that I'm doing to produce the embossed loftwing on the shield:
Davide Bigazzi Performing Repoussé to Make a Decorative Silver Plate
We also have Victoria Lansford, who has written many books on the subject:
Another great video by Victoria Lansford on using the art of Eastern Repoussé
One interesting final note, I am willing to bet you've seen a famous repoussé piece of artwork and haven't even realized it. One of the most famous works done using repoussé is none other than the Statue of Liberty in New York, USA. That was done using repoussé on VERY MASSIVE copper sheet/plate. It's the same technique only at a sculptural and architectural scale. VERY impressive.
It's a fun craft to learn. The work is very effort intensive and as such, pieces made using this technique are VERY expensive. They are beautiful though!
Now back to our regularly scheduled program of my project! Thanks, everyone!
