Tooling leather goes back so far in history that it’s impossible to say when it started. Archeologists have found preserved examples from over 3,000 years ago (or at least that’s what the internet says).
Animal hides from hunts were among the first materials used for making clothing, shelters and weapons, so it’s not too farfetched too think of the art of carving them as prehistoric. Now we use methods for tanning and tooling hides that have been perfected over thousands of years for making all kinds of stuff, even your old Bendix carb uses leather for the accelerator pump.
In this article I am going to cover some basics in carving and tooling that should be just about enough to get you into trouble. It seem like the people that I have talked to on the subject were not only interested, but eager to jump in and take a stab at it. Once people started asking “where do I start” I realized if someone wanted to make their own seat they would have a lot of time and money wrapped up in it. Most people seem to be interested in the carving and tooling aspect more so than shaping foam and cutting patterns anyway. If you don’t know how to tool leather at all (or at least have never actually done it) it might seem like a big jump. Mastering the art of carving leather can take years. I am always finding new and better ways to get what I am looking for. However, I have been teaching others how to do it for a while now, and even those who have said that they have no artistic talent constantly amaze themselves at just how nice event the first thing they do can turn out with the right tools and a little know how. As far as our seat kits go though, we do toss in a couple scraps so that you can get a feel for it first.
The first thing you will need is a good solid work space.
If you are starting from scratch you will want to be sure to have the whole seat done and ready to go together even the holes for lacing. There is nothing worse than spending hours on a seat and then getting the holes off. Once you put a hole in the wrong spot or they just don’t line up right it’s done.
I am going to be using one of our seat kits for this seat. Once you know the shape and size, you can get started on the artwork. If you can’t draw as well as you would like your seat to turn out you’re in luck. In order to transfer the image onto the leather I am using tracing film, and you can trace anything you want onto it. Whether you drew it or printed it off from your computer. I like to draw what I am putting on the leather right on the film. For me drawing something twice is enough, but tracing film is more like plastic than paper so it smears a lot and is hard to erase from. An old school pink eraser seems to work best, and by putting a piece of paper under your hand you will help control the smearing.
Start by tracing around the leather top to give you some guide lines. From here it’s all you. Once you have your art work ready you will need to get your leather ready. You will need to use vegetable tanned top grain leather to do this. Hides are measured in ounces. Seven to Eight ounce is around one eighth inch thick, which is about what you want to use for your top. The thinner you go, the less depth you will get. There are ways to thin out certain parts to shape it the way you want when covering your seat, but let’s stick to the tooling. You will need to get your leather wet; this is known as casing the leather. You need to get it soaked through and then let it dry out a bit. The leather will bounce back like a sponge and wrinkle when you drag your knife through it if it’s too wet. Once the leather has had a while to set up, you simply put your tracing film over it and re-draw your lines with a stylus (a ball point pen works well also) applying a steady pressure.
When all your lines are transferred to the leather you can get to cutting. A swivel knife is the way to go, it’s easy to control and maintain an even depth of your cut. Holding the knife at about a 45 degree angle, you will be pulling the knife towards yourself, despite what your scout master told you. As you go around the curves of your design you can control the knife by turning the head between your thumb and your middle finder, hence the name swivel knife. Once all of the lines are cut you can start stamping, but there is a bit more to it than that.
Shaping out your design is more like sculpting clay than just hitting a stamp. The leather at this point is very malleable and even though you are using a hammer to get depth, special care must be taken even in the way the tool is held against the leather, and it does not all have to be done with stamping tools. If you press your nail into the leather it will stay, if you drag something smooth across it, there will be impressions. Look at any leather smith and you will see someone who does it different.
Most of what you will learn from working with leather will be tricks you come up with to get the results you are after, especially when you have a few years under your belt. If you are more interested in getting a seat on your bike than years under your belt, I put an hour long instructional DVD together that covers a bit more than what I could fit into this article, but like I said before, this should be just about enough to get you into trouble.