Repoussé Tools for the “Pitch Method”
There is not very much in print regarding repoussé, especially in any great detail. That said, I am not going to produce a treatise, but rather show the more common tools of repoussé, and how some of them are used. I will also try to address some commonly asked questions.
This segment will deal with some of the tools used for the pitch method of repoussé, often referred to as “high relief chasing.”
Below is an image showing how pitch appears direct from the manufacturer. It arrives in various sized chunks, and is like peanut brittle in its consistency.
If you were to hit it with a hammer, it would shatter into many pieces.
To use it, one needs to melt it onto a firm, solid substrate. I personally use a heavy steel plate, at least 3/8″ thick, with a bar mounted on the bottom that can be secured into a vise.
Other folks use a “pitch pot” , which looks like half of a hollowed out bowling ball, which is then placed in another concave surface (a wood stump would suffice) so the pot can be rotated, yet still have a firm base.
I choose to use the steel plate, as I can walk around the vise as I work.
Note: I have tried a heavy wood board as a substrate, but have found that it is too flexible, and thus, the pitch-bed dislodges from the wood, and then it has to be reset.
Below is an image showing a heat gun that I use to melt the pitch onto the steel substrate.
I use the same gun for removing the workpiece from the pitch. The type of gun is a simple tool for paint removal. I believe I paid about $35.00 for it, and it works fine.
When melting the pitch, be careful not to get it too hot, as it will lose its properties if overheated repeatedly. If it begins to bubble, back off on the heat for a while, then continue. I use a piece of steel with a chisel-like edge on the end to spread and shape the pitch-bed.
When initially making the pitch-bed, you should block up the sides of the bed with bars of iron. Otherwise, the pitch will seek its own level, and all you will have is a big blob of pitch with no depth to it.
Below is an image of a pitch-bed for concave work.
The form of the last piece I worked on, “Jacob Marley” is still visable.
The next image shows the pitch-bed used for the convex work.
Again you can plainly see the ghost of Jacob Marley in the pitch (sorry.)
To lift the workpiece off the pitch, simply heat the area on and around the workpiece, and when the pitch begins to soften, use a pliers to gently lift the workpiece off the pitch. Try not to get the pitch too hot, as the hotter it is, the more pitch will cling to the workpiece. Pitch is messy at best to remove. Some of it may be removed from the workpiece by wiping with a rag while still hot. The residue can be removed with mineral spirits.
The purpose of pitch is to back up the metal, bolstering it firmly while being worked with the punches. When working, the pitch should be warmer than room temperature, but still very stiff. It should not be stone cold, as it is then too brittle, and will crack. Try for the happy medium, which may mean occasional warming with the heat gun, and then a brief wait to cool it down some. If too hot, moist towels may be applied to enhance cooling.
If making a bust such as Jacob Marley, initially sink the metal workpiece in a wood dish, like the one seen below. Use a dome faced hammer to force the material down into the dish.
I choose to use a laminated block, so the wood will be less inclined to crack. The dish is 3″ in diameter, 1 1/2″ deep, and the edges have been rounded. I leave the middle boards a little long, so I can fasten the block into a vise.
When sinking the metal into the dish, concentrate your blows around the perimeter, as you do not want to stretch the center too much, as this is where the proudest features will be located. In the case of a bust, the nose in particular really stretches the material to its extreme, so be careful not to break through by carefully monitoring the workpiece with a calipers.
Below we see the many small punches for doing the detail work.
These punches are made of high carbon steel. When making them, simply make yourself a bunch of punch blanks of various sizes, so when you need a specific shape, all you need to do is refine the end to the desired shape by filing or grinding, then harden and temper the tip.
Below is a bird’s eye view of the various tip shapes.
Mind you, there can be a multitude of punches, but don’t let that fact overwhelm you. Make them as you need them, and eventually you will have quite the fine set.
In another post, I will discuss and show the tools for hammer and stake raising, otherwise known as “French Repoussé”.
“The beautiful thing about learning is nobody can take it away from you.”…..B.B. King