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Posted: 9/9/2002 12:00:44 PM EDT
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sig_230 asked me to discuss handmade knives in general, and specifically the handmade forged blade. I have an article on my website about the difference between the stock removal method of creating a knife and the forged method. It is a short and simple article. If anyone wants to take a look at it, here's a link: What is a Bladesmith? Another thing sig_230 mentioned was the functional difference between a knife done by stock removal and a forged blade. The bottom line is that it all boils down to the man making the knife, his skills, and his understanding of the steel with which he's working. There was a lot of hoopla for years about the superior merits of a forged blade. There are two things to keep in mind however. One is that with modern high tech / high alloy steels, we've got some really tough and impressive knives being produced by stock removal. I do believe the fact that forging a blade causes the grain to flow with the shape of the knife, thus creating a very strong blade. However, the second thing to keep in mind is that the mere act of forging a blade does not in itself produce a high quality tool. In fact, in the wrong hands, forging blades has more potential for introducing serious problems than it does producing a superior cutting tool. The bladesmith must have an intimate understanding of the steel he is working. This will be touched on later. Some of the things that make a good knife are good design for the primary purpose (form follows function), good weight and balance (again dictated by the primary purpose), and edge holding ability (achieved by proper edge geometry and proper heat-treating). If you have the June 2002 issue of Blade Magazine, look on page 69. You'll see where they quoted me in the sidebar as saying, "A knife should feel like an extension of the hand, as if cutting with your finger". By the way, if you look on page 70 of the same issue, you'll see sig_230's knife being balanced on the editor's finger. One more quote and then I'll move on. On the homepage of my website you'll see the quote, "A good knife should look good of course, but it should also feel like an extension of the hand, have symmetry, balance, flow, proper edge geometry and heat treat, be tough, and hold an edge well". The point I'm making is that whether a knife was made by stock removal or by forging the most important thing is that all these qualities mentioned above have been met. |
Let's get started on the forging part of the discussion. With forging we are taking the piece of steel up to a temperature at which it becomes malleable, so that it can be moved and shaped with a hammer. Here you'll see me forging a blade. In this case I am using the bar of steel as its own handle rather than holding a smaller piece with tongs. I remember this day very well. It was a record hot summer. We had about 40 days of no rain, and temperatures which with the heat index, reached 113 degrees F. A few steps from me was my forge (that fire breathing dragon), cranked up to somewhere in the neighborhood of 1850 - 2000 degrees F. *whew* In the photo above, I've already forged the tip, defined the ricasso shoulders, and started forging the bevels into the blade. I have switched to a smaller hammer and have begun to refine the bevels. This one was camp knife with a 10" blade. To give you a better idea of what I am doing, here is another photo. This time of a smaller hunter-sized blade.  The top piece is the bar stock. In this case, a piece of 1084 high carbon spring steel. Beneath the piece of raw mill stock is a blade that has been reasonably forged to shape. The basic profile has been established, the tang has been drawn out, the ricasso, heel, and choil area are defined, the distal taper from ricasso to tip and ricasso to the butt of the tang have been forged in, and the blade bevels have been formed. You may notice the the blade looks larger than the stock. This is another thing I love about forging blades. My design is not limited to the boundaries or dimensions of the piece of stock. This is because I am not grinding away material to shape the knife. I am merely redistributing the mass from one area to another, more of less like shaping the blade from a lump of clay. The ginder will be used to a degree later to refine the profile a bit, clean off the scale from forging, and get everything really flat. |
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After forging, I use a series of thermal treatments to reduce grain size, get an even distribution of carbides in the ferrite matrix, relieve stresses induced by the forging process, and to anneal (or soften) the steel to make it easier to work by hand. I do this part in my shop, in a heat-treat furnace. It can be done at the forge. Many bladesmiths do, and I have as well. The reason I choose to use the heat-treat furnace for these thermal treatments is because it is very accurate and I can have consistant results. Everything mentioned so far has eaten up our first day. One thing I am often asked is "How many knives can you make in a day". The answer is "None". This is a hard lengthy process. It's one of many reasons that the cost is high for a handmade knife in a one man shop.  Now the thermo-cycling, normalizing, and annealing has been done. Here we have the blade cleaned up a bit. It was ground clean to a 120 grit finish. For the particular process I use, this blade will be worked by hand to a 400 grit finish before heat-treating. In the photo above you can see the profile. It's starting to look like a knife. This is a hidden tang knife. That is, the tang of the knife will be inside the handle using a technique called mortised tang construction. In the main part of the photo the blade is being held edge down so that you can see the distal taper on the blade and the tang. Distal taper helps create a light and well balanced knife without sacrificing strength. Okay guys, I've got to hit the shop again, since this is my sole source of income. If any interest is shown in this, I will continue as I can. Since I'm not sure when I'll be back for part 2 (if there is one), I'll go ahead and post a photo of a completed knife to give you an idea of the metamorphosis from ugly raw materials to a nice handmade tool.  This is a differentially heat-treated blade with nickel silver hardware and a nice piece of Arizona Desert Ironwood for the handle, which has been hand-rubbed to a 2000 grit finish, then hand-rubbed with wax. It has a wicked little sharpened chisel-ground clip. |
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First I would like to thank Terry for his time, and the contribution to this board. Remember you can post knives for sale in the EE. As for the terms a brought up by SIG, I will attempt to add my 2cents. Choil- The area in between the edge of the blade and handle. It is where the edge tapers down in to the handle. A stiletto style knife like the Sykes(sp?) would not posses a Choil. Thermo Cycling is the process of slowly rasing the temp of the steel and cooling it to encourage proper grain growth and to heat treat (harden) the knife. Annealing - Is when you heat metal usually with a low flame or torch to when it is soft, not a red-hot like with forging. The ricasso is the area between the choil and the spine (backedge) of the knife Usually where the makers logo or name goes. I wish I had a picture to point to but I think the explaination should help some what. JerrY |
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Pretty good description. This is the best I could throw together on short notice. Nomenclature for a Fixed Blade  This is pretty generic. Not all knives have a guard, or a choil, or a ricasso, or a clip. Some folks call the handle a hilt. There are also other parts which don't appear on this knife. If a knife has brass, nickel silver, stainless steel (or whatever) pieces where the guard is on this knife, but they don't protrude above or below the spine or handle, they are referred to as bolsters. Pocket knives generally have bolsters on both ends. That little hickey that protrudes ever-so-slightly below the cutting edge on a pocket knife is called a kick. On some Bowies you will see a non-functional decorative piece behind the guard (between the guard and handle). This is referred to as a ferrule. There's much more but I'm just about brain dead right now. You get the idea. One thing I would change in JerrY's description of thermo-cycling is that it is a step to promote grain size reduction rather than growth. Different makers use slightly different terminology for heat-treating. Some don't use the term thermo-cycling at all. Some use the terms thermo-cycling and normalizing synonymously. I don't. When I thermo-cycle, I bring the steel up to to temp, then rapidly cool by waving the piece in the air. The primary purpose of this is to keep grain growth in check. It helps reduce the grain size. I often perform this during the forging process. When I normalize, I bring the steel up to to temp and allow it to slow cool in still air. This also helps reduce grain size and relieve stresses, but one primary benefit of this step is that it helps create an even distribution of the carbides in the ferrite matrix. In any given piece of steel there will usually more carbon concentrated in one area than another area adjacent to it. Normalizing, when done correctly creates a homogenous piece of steel with a relatively even distribution of carbon throughout. The bottom line is the knife will cut better. I see more problems with terminology here. Steel in its simplest form is cementite (carbon) in ferrite (iron). Here's another excerpt from an article on my website. "Steel is a combination of iron and carbon. In its softened state, the base is a matrix composed of simple iron molecules (ferrite), in which are suspended molecules of iron carbide (cementite)." If you need to know more check out Effects of Alloying Elements in Steel on my website. There are numerous types of annealing. The most commonly known method is to bring the steel up to critical temperature and v-e-e-e-r-y slowly cool. Some people put the hot steel in vermiculite, some in vermiculite and wood ash, some in wood ash and sand -- the list goes on an on. The idea is to insulate the hot steel so that it cools extremely slowly. Sometimes it will still be hot the next day. This slow cooling make the steel soft and easier to file, sand, grind, drill, etc. The method mentioned by JerrY is a form of annealing to draw brittleness out of the steel in a particular such as the tang to make it easier to drill after the hardening process. I just call it drawing. There is no way to cover everything. Come to think of it, I don't know anyone who knows it all, least of all me.  |
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