Leather:
Leathercraft can be used alone to produce armors made entirely of leather, but the craft of leatherwork spills over into just about any of the other armoring areas. Nearly all plate harnesses require leatherwork of some kind – straps and articulations are common examples.
Leather has an advantage in that it is fairly easy to work, and does not require much in the way of tools. However, the levels of effort put into finely crafted leatherwork can rival that of the best plate armor. Leather armor also has a disadvantage in that leather itself can be quite expensive.
Like maille, leather armor has only minimal tool requirements. However, leatherwork can be a bit messy. Since you will likely be working with bottles of dye (which stain everything, including leather), hot water, and sharp knives, working with leather armor requires a bit more of a shop than working with maille. (see also: Beginner’s Tips for Leatherworking and Water Hardened Leather Technique)
Some of the tools you might encounter while working with leather are:
Leather hole punches
Working with leather always requires punching holes in it. There are two types of punches. Hand-held punches that you use with a hammer, punching into a soft surface (nylon cutting boards work well); and rotary punches, that work like tongs. The advantage of the hand-held punch is that the punch can be brought to bear anywhere on the work surface, whereas tong punches can only punch near the edges of a piece.
Razors and Utility Knives
Razor kits come in a variety of handle and blade styles. They are very useful precision knives, and extremely sharp with new blades. Utility knives can be used for cutting out larger pieces.
Swivel knife
Swivel knives are a special kind of knife used for cutting out patterns on the face of leather.
Strap cutter
Like the name implies, this tool makes quick work of cutting strips or straps out of a large piece of leather. You can do the job with a straight edge and a utility knife, but a strap cutter will pay for itself the first time you use it.
Rawhide mallet
Most leatherworking punches and dies should not be struck with metal hammers. Use a rawhide mallet instead. Wooden or plastic mallets can also be used.
Ball peen hammer
When you need a little more “oomph” than the rawhide or wooden mallets are providing, ball peens come in handy.
Stamp sets
If you want to tool your leather, there are some stamps available. Unfortunately, most leatherworking stamps are geared towards the country and western crowd, and not the medieval armorer. Nonetheless, some can be useful.
Modeling tools
Similar to stamps, modeling tools are used for tooling leather. However, modeling tools are mostly used to mold designs into the face of leather after the desired patterns have been cut into it.
Edge Beveler
To give your straps and belts a finished look, you should bevel the edges.
Awl
Awls are handy for piercing (not punching) holes through leather and fabric. Generally, when you put a hole into fabric, you want to pierce a hole in the material, rather than punch. The reason is that punching actually removes material, and cuts the fibers that pass through the area where the hole is. Piercing the hole with an awl simply spreads the fibers and results in a stronger finished piece.
Leather hand needle
You’ll need one of these if you are going to do any sewing of leather.
Lacing Chisels
These tools come in a variety of sizes, but they all look like funny-shaped forks. They are used for punching evenly spaced holes in leather, for lacing.
Latex gloves
If you don’t wear rubber gloves while dying leather, you will dye yourself as well, and it can take weeks for the dye to wear off. Unless you want to explain your hobby to everyone you meet for weeks on end, wear rubber gloves while dying leather.
Electric frying pan
Many leather objects, including armors, are made of cuir-bouli, or “boiled” leather. While not actually boiled, this type of leatherwork involves immersing a leather object in very hot water, shaping it, and allowing it to dry. As a modern convention, frequently after the object is dry it will be impregnated with molten wax to add additional rigidity. An electric frying pan or wok is an excellent way to melt wax. Just be careful not to set it on fire. (see also: Wax Hardened Leather Technique)