DavidB wrote:Wow! Thank you all for the info.
I take it that it can be possible to make
a decent knife from a kit? If so, are there
any suggestions of what to look for; such
as type/composition of steel, hardness, etc.?
This is to be a plain-vanilla, utility knife. Like you
would use in the field; so the main quality is
strength.
You are asking a lot of different questions here.
Think of a knife in terms of at least four characteristics: Design, Steel, Heat Treat, and Edge Geometry.
Design refers to the way the knife is shaped. This includes blade length, thickness, profile, handle type, how the handle is oriented with the blade and more. Some designs are pretty clear about what they are good for. Think of a dagger, sharp on both sides, very pointed and the point lies directly in line with the center axis of the handle. This is a knife for sticking things. Now think of a classic skinner, the blade has a big belly, the tip lies far above the center axis of the handle. This is for making long sweeping cuts. Most utility blades are a compromise of features. If you think you are going to need it for long sweeping cuts like you use a skinner for, you design more belly. If you think you will need it to stick a pig, or do fine work with the point, you want the point closer to the center axis of the handle. Think about handles and guards. Some shapes are better for swinging for slashing, some are better for pushing to stab, some are better for pull cuts.
Now the steel. Compromise again. Stainless or Carbon steel. Stainless resists rust a bit better, carbon steel, in general is easier for the home smith to heat treat without special equipment. Some people think that carbon steel holds an edge better. Some steels are easy to work with, but they have lower abrasion resistance, some are more resistant to abrasion but are harder to shape and sharpen.
Heat treat makes the steel perform. Again, there is a balance here. Too hard and the steel loses toughness or ability to withstand side loads. Too soft and the knife won't be sharp. Too hard and the edge will chip. Just right and the knife is sharp, tough enough to take the use it will get, the edge will last and if it is over-stressed it will be more easily corrected. Then there are techniques like differential heat treating or tempering that lets you create a knife that has both a hard edge and a softer spine giving you the best of both worlds.
Edge geometry refers to how the knife edge is shaped. Hollow ground, V grind (often with a secondary bevel), Convex are three popular choices. Hollow ground uses round wheels to reduce the blade thickness above the edge. This is used to lighten the blade, make it easier to stick into things (reduced cross section) and to make it easy to get a very refined edge. The downside is that the carbides in the edge are not as well supported as in a V or Convex grind so the edge tends to be sharp, but a little more prone to damage. Think of a straight razor as most are hollow ground. Very sharp, but not tough, you don't want to make a chopping knife with a hollow grind if you have other choices. The V grind is common on Scandi knives and often on wood working tools. This grind is preferred by some bushcrafters (Ray Meers for example) as they are great for wood working. The V grind supports the edge better than the hollow grind and is often used on choppers as well. Some people like the V grind because it is easy to sharpen using stones. The convex grind takes the cross section of a bullet. This edge type supports the edge carbides the most, but is harder to do (can't be done on an automated machine that I know of). Some people find the convex a little harder to sharpen (it isn't that hard). The convex is great on a chopping blade but also works well for other uses.
So, what do you want your knife to do? When I think of a utility blade I think of a 4 inch blade that is less than 1/4 inch thick (down to maybe 1/8 inches thick). I like the point near the center axis of the handle or a little higher with moderate belly. I prefer a convex grind. I prefer a handle with no guard but with a finger groove up front. The blade needs to be useful in several grip styles. Give me carbon steel heat treated to balance hardness with toughness. I would want the balance of the knife to be at the first finger or back.
If you are really rough on a knife, you might go thicker and get a heat treatment that biases towards toughness.
If you want a knife to use to chop brush, you might want more belly, more toughness, more forward blade weight and a handle that lets you control the blade in a chop.
This seems tougher than it is. In reality, you can use almost any knife for almost anything. And as for handles, your hand is very adaptable. Find a knife style that looks good to you and that captures most of the features you want.
If I wanted to make a basic utility knife for camping, hunting, etc. and I didn't want to have to forge or shape the blade and heat treat it myself, I would order something like this:
http://www.knifemaking.com/product-p/nw301.htm
A basic style with good steel and a good heat treat. You can find the same basic style here in stainless as well. This knife is not going to be as thick as is the current trend, but it will be tough enough for 99% of reasonable use and will cut great.