A hide of genuine leather is nature's product and caution must be exercised in cutting one. The above diagram shows various areas of a hide and they are cut as follows:
Section A should be used in cutting seat tops, inside backs, cushion bands, and other sections that will receive the most strain and usage of flexing. Section A is the prime portion of the hide.
Section B should be used for outside arms, backs, hidden bands, or other parts of furniture that will receive little or no flexing. The flank sections must be used on outside backs and nonwearing surfaces in order to avoid trouble. Flank fibers run generally in one direction as indicated by the arrow. In applying flank sections to a chair, the first pull should be taken in the direction of the arrow. A stretch at right angles to the direction of the arrow may cause the finish to crack.
THE LEATHER PROCESS
|1 CURING |
Deterioration begins immediately when a cow is killed. After the hides are removed from the carcass, they are salted through and through at the slaughterhouses to prevent decay. After they are salted, 55% of the water in the hide is removed, and they are dried for 3 to 6 days. The rawhides are then sold to tanneries.
|2 SOAKING |
In order for the tanning process to work properly, the dry salted hides must be washed free of the salt. This is done by soaking the hides in water to which chemical wetting agents (similar to household detergents) and disinfectants are usually added for 8 to 20 hours, depending on the thickness of the hides. This soaking procedure rehydrates the hides to their original flaccid condition and removes the dirt.
|3 DE-HAIRING |
The hair must now be removed from the hides. This is done by soaking the hides in chemicals, or depilatory agents, which destroy the hair by attacking the hair root so it will release freely from the hides, loosen the epidermis, and remove certain soluble skin proteins that lie within the hide substance without destroying the desirable collagen of the hides.
|5 DE-LIMING |
All the depilatory chemicals must now be removed from the hides. This is done by washing the hides in ammonium sulfate or ammonium chloride and then clear water in big drums. These chemicals not only clean the depilatory chemicals from the hides, they also adjust the acid-alkaline conditions (pH) to the proper point for receiving the bate-which are enzymes similar to those found in the digestive system of animals. When the bates are applied, they attack and destroy most of the remaining undesirable constituents of the hide.
|6 PICKLING |
The hides must be placed in an acid environment (low pH) so they will be ready to accept the tanning materials, because chrome tanning agents are not soluble under alkaline conditions. This is accomplished by adding salt and acid to the hides. This is a preserving process in itself, and hides can be kept in this state for extended periods of time without any deterioration.
|7 TANNING |
The raw collagen fibers of the hides must be converted into a stable product which is no longer susceptible to rotting. This is done by adding chrome tanning agents to the hides in a revolving drum. These tanning agents also significantly improve the hide's dimensional stability, abrasion resistance, resistance to chemicals and to heat, the ability to flex innumerable times without breaking, and the ability to endure repeated cycles of wetting and drying.
|9 SPLITTING |
The hides must now be split into the desired thickness. Unsplit hides average to be 5mm thick. The thickness for upholstery leathers range from .9mm to 2.0mm. The hides are put through a splitting machine that is set to split the hides to the desired thickness. It cuts the top grain off first. Another layer, and sometimes two, are cut. These layers are called splits.
|10 SHAVING |
The thickness of the hides must be made uniform all over the hide. This is done with a shaving machine through which the hides are run. The helical shaped cutting blades level the overall thickness to exact specifications and open the fiber structure to better receive subsequent chemical processing.
|11 RE-TANNING |
This process is done to impart special end-use properties with other tanning chemicals. The substances used add solidity and body to chrome leather and help minimize variations in the character of the leather that may still exist between different parts of the hide.
|12 COLORING |
As soon as the retanning process is completed, aniline dyes, derived primarily from petroleum and added to very hot water, are added to rotating drums to penetrate the hides for desired color.
|13 FATLIQUORING |
This is the last of the wet chemical operations to which the leather will be subjected. Fatliquoring has the most pronounced effect on how soft a leather will be and it contributes greatly to its tensile strength. The more fatliquors that are added, the softer the hides will be.
|14 SETTING OUT |
This operation smoothes and stretches the hide, while compressing and squeezing out the excess moisture. This puts the hides in the proper condition for drying.
17 DRY MILLING
|18 BUFFING |
This process improves the final appearance of the hides by lightly sanding the surface to remove some of the natural imperfections such as scratches, healed scars, etc. It provides the hide with better cutting yield.
|19 FINISHING |
This process applies film-forming materials on the surface of the hide. Here is where layers of pigments are added if required. This process also adds the protective sealant to the surface.
20 PLATING (EMBOSSING)
Making Leather Armour:
Suppose you were drawing up specifications for the perfect armor. It would be easy to make from inexpensive materials using commonly available tools. It would be light, strong and rustproof. It would look good. And, of course, it would be period.
Hardened leather, also known as courbouilli, meets all of those requirements. Since discovering how easy it is to make, I have used it to make forearm and elbow protectors, greaves, a half gauntlet, body armor, and edging for my shield. I even made a hardened leather hockey cup, on the theory that the usual white plastic version was the most strikingly mundane item in my armor bag.
In this essay, I will describe how to make several pieces of armor out of hardened leather: a bazuband (a medieval Islamic forearm and elbow protector), a klibanion (Byzantine body armor), a gauntlet and a basket hilt. The techniques described can be applied to a wide variety of other pieces.
To start, you need some leather. It should be vegetable tanned leather rather than chrome tanned leather, and undyed. Chrome tanned, which is the most common modern variety, can usually be recognized by the grey color of the cut edge (unless the edge has been dyed). Vegetable tanned leather is used for carving, making belts and similar projects; it is often described as saddle skirting. Its color, before you harden it, is a light tan.
The thickness of leather is defined in ounces per square foot. One ounce corresponds to a thickness of 1/64"; what is actually measured is usually thickness rather than weight. Ideally you should use at least 12 or 13 ounce leather. Leather as light as 8 or 9 ounces can be used for armor, at least over places that are not too vulnerable; if you make your bazuband out of something that light, use two thicknesses over the elbow. The klibanion is made of overlapping lamellae, giving a total thickness of about twice the thickness of a single layer of leather, so 8 ounce provides at least minimal protection.
Before you start making hardened leather armor, let me give you three warnings. The first is that, although beeswax is attractive, pleasant smelling stuff, people who do not make armor and do share your kitchen may object to finding hardened drops of it scattered over the floor, stove, and countertops. The problem can be minimized by being careful with the molten wax. If you are not good at being careful, you will want to know that hardened wax is easier to remove if you use something soaked in hot water.
The second warning is that wax can burn-which is why it is used to make candles. I have never had beeswax catch fire on me when I was using it to harden leather, but I expect it could happen if you got it too hot. I have no experience with paraffin or other waxes that you might use instead. Be careful, and keep a fire extinguisher nearby.
My final warning is to remind you that the bag that separates your inside from your outside is made of leather. Any tool designed to cut leather is also designed to cut you, so be careful. As Kipling put it in "The Wrong Thing," "Do your work with your heart's blood, but no need to let it show."
To Make a Bazuband
Figure 1 shows what a simple bazuband looks like; Figure 2 shows the piece of leather you will use. The measurements are the circumference of the wrist (a), the maximum circumference of the forearm (b) and the distance from the wrist to the crease that divides the forearm from the upper arm (c). I have given the measurements of the piece for my arm as an example.
Cut out the piece, fill a pot with cold water from the tap, and put the leather in to soak; if you do not have a pot big enough, use the sink or bathtub. After the leather has soaked for half an hour or so it gets flexible and slightly stretchy. If you are making something that requires a good deal of stretching, such as a bazuband or greave, let the leather soak overnight, then take it out, cover it with a damp towel, and leave it for eight hours or so.
If you were simply making a forearm guard, all you would have to do to shape it would be wrap it around your arm (with padding), or around anything else about the same shape and size, and let it dry. A bazuband is a little trickier because of the part that covers the elbow, which is curved like part of a sphere. To make that, you have to stretch the central portion of the leather that goes over the elbow-the shaded area on Figure 2. The different degrees of shading are intended to give a rough idea of what is stretched how much.
One way is to use a medium sized bowl-say 6"-8" in diameter. Put the bowl upside down on a convenient counter and stretch the leather over it by hand. Another way is to use two bowls, one a little larger than the other, with the leather in between.
When the leather has been stretched enough, the next step is to tie it to the form. The form should be something about the size and shape the bazuband is going to be. That means that it should be cylindrical for eight inches or so, with a diameter of about four or five inches and an end that is roughly spherical-increase the numbers a little if you are a giant.
I happen to have a steel bazuband the right size, so I cover it with Saran Wrap to protect it from the wet leather and use it as my form. If you do not have any antique armor lying around, look on the shelf where you keep empty jars, wine bottles, and the like; you should be able to find something about the right size and shape. It does not have to be exact; you will be able to do a certain amount of reshaping of the damp leather after you take it off the form. If you are really ambitious and good at whittling, you could probably make a wooden form and use it to make bazubands for everyone in your group.
Tie the wet leather onto the form, using strips of cloth to avoid marking the leather. Better yet, use a roller bandage-one of those elastic bandages they sell to tie up a sprain, made out of stuff that sticks to itself. You probably have one left around from the time you sprained your ankle fighting.
The basic idea is to get the wet leather tied tightly onto the form, so that when it dries it will have the shape of the form. The only hard part is the spherical section covering the elbow. Work that onto the corresponding part of the form by hand, trying to get it as smooth and wrinkle free as possible. I generally leave it for fifteen or twenty minutes, in the hope that it will stretch a bit more, then untie that part and try again. When you are finally satisfied, leave it for a few hours to dry.
At that point the leather should be stiff enough to hold its shape as long as you treat it gently; take it off the form so the inside as well as the outside can dry. If necessary reshape it a bit-open up the cylinder that goes over your forearm if it is too tight, or close it a little if it is too loose. Then leave it somewhere out of the way to finish drying. Do not start the next step until the leather is thoroughly dry, which probably means waiting several days; if you try to harden leather that is still a little damp, horrible things will happen to it.
Leather is hardened by impregnating it with beeswax. Some people do this by melting wax in a large pot and putting in the leather. This method requires a lot of wax, and I have never tried it. I harden my leather in the oven, using a large pan or a sheet of aluminum foil. In the pan I put the bazuband, with the hollow side up and a large chunk-half a pound or so-of beeswax inside it. Then I put the pan, leather, and wax in an oven set at about 220deg. .
When the leather is hot and the wax beginning to soften a little, take the pan out, rub the wax all over the surface of the leather, and put the pan (and wax and bazuband) back in the oven. Try not to spill wax anywhere where it is likely to catch fire. Continue the process for half an hour or more, rubbing wax on both sides, letting chunks of softened wax melt in the hollow part of the bazuband and running the melted wax around the inside, until the leather is soaked through with wax. Then turn off the oven and take out the pan, bazuband, and what is left of the wax. As long as the leather is hot the bazuband is reasonably flexible, so do any last minute reshaping to get the size just right, then let it cool and harden.
This is a simple bazuband, made of only one piece of leather, so all that remains to do is to punch holes in it (as shown in Figure 1), run a leather thong through the holes, and put in whatever kind of padding you prefer. You are done. You now have light, strong, rustproof protection for your sword arm and elbow. It is a beautiful brown color and looks (and is) very real.
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