Handmade Knife & Sheath Construction
Principles of Knife Selection: PDF
Steel: Mostly CPM S30V stainless, high-carbon steels, O-1 tool steel, and the steel from large saw blades. Beginning in 2013, all knives made from sawblade will be heat-treated and tempered to approximately Rc. 57-59, unless otherwise requested, stated, and/or marked. Knives made from S30V are subject to a 20% surcharge, due to the extra cost of the steel, additional abrasives required, and additional grinding time. But if you like good stainless, this is my favorite.
Heat Treating: All my air-hardening steels (A-2, D-2, ATS-34, 154CM, S30V) are given a state-of-the-art cryogenic heat treat by Paul Bos.
Handle materials: Phenolic Laminate (called Micarta by one manufacturer) is my first choice. Canvas Phenoliccontains a coarse weave of fabric, producing a nice grippy texture. Linen Phenolic contains a finer weave of cloth; and Paper Phenolic contains layers of paper, which are often almost invisible. Many colors are available in each kind. I use mostly black, green, and brown Canvas Phenolic. I like to keep some bright red Linen around, too.
Dymondwood is my other favorite handle material. It is a dyed, plastic-impregnated hardwood laminate. It is supremely easy to work with, and is available in over 50 colors and color combinations. The color combinations give a nice layered look. One significant advantage Dymondwood has over natural wood, is that it is impervious to water.
Sheaths are hand made by me for each individual knife. Leather – vertical pouch, and vertical snapped retainer types come standard with most knives. My horizontal sheath is made of leather with a snapped retainer, and offers many carry positions. Kydex is preferred for neck sheaths, and for vertical sheaths used around water where leather would retain too much moisture, and deteriorate. Inside-the-waistband sheaths are a good, snag-free way to carry a knife, and give excellent concealment if that is needed. Left-hand sheaths have benefits for both right- and left-handed users. I will be happy to help fill your special needs.
Be sure to read the “Knife Related Information and Philosophy” category in my blog!
Tangs–Fully Exposed, or Hidden?
What You Can’t Always See–A Peek Inside
Full tangs, hidden tangs–which are better? Which are stronger? How strong is strong enough? Let’s look at some of the factors.
In order to be dependable, a knife must have a sturdy handle. What are the factors involved? First, materials. The blade must not be too brittle, especially at the point where it comes out of the handle. “Stress risers”, sharp nicks or angles in the outline of the knife, are often the culprits that lead to blade-handle failure. Then the handle material must be able to withstand whatever stresses it will be subjected to, often including changes in temperature, changes in humidity (ranging from total immersion in water, to baking in direct sunlight in the dry desert), whatever amount of impact it will encounter in normal use, abrasion, and often, very slight bending. The final ingredient of a good handle is the fasteners and adhesives used in its assembly.
If a blade is hardened the same in all portions, the cutting edge is a good indicator of hardness. If the edge is resilient enough to withstand heavy cutting, the rest of the blade is probably all right. If the knife is differential tempered, the blade-handle juncture can be brought down to a spring temper or softer.
Stress Risers – the worst ones often occur just inside the guard where they are almost impossible to see. Mass-produced knives often have a sharp, perfect 90-degree angle, coming from a narrow tang to a wide blade. This makes it easy to fit mass-produced guards to the knives. The example here is the venerable USMC knife, made by various companies including Camillus, Ka-Bar, and Ontario, and carried by our nation’s armed forces by the millions over the last 60+ years.
In spite of what I would consider a horrible design defect, this much-loved knife has served millions of Americans faithfully. And yes, a few have broken–guess where?
Factories are factories, and have to do everything possible to save time. But custom knifemakers have no reason to follow their examples on certain points. We are here to do better. We are here to build knives that will out-perform factory knives, and that are specifically suited to the needs of the individual person. At left are some examples of actual blades and a working pattern from my shop.
Notice the rounded corners at the blade-handle jucture. I never use anything smaller than a 5/32″ chainsaw file here (as shown on the top knife). Usually, I use a 6-inch round-back file on the smallest knife in the picture, and either a 10-inch round-back file, or a 2-inch contact wheel on the larger hidden-tang knives, which are the same radii I use on my fully-exposed tang. And I make the transition as slowly as possible, and still keep the handle the size I want it immediately behind the guard.
Handle material – there are many good choices. Wood is lightweight, and can be extremely beautiful. Its downfall is that it tends to crack, especially in wet environments. Waxy woods, Dymondwood, and stabilized woods solve this problem by being water-resistant or waterproof. Leather is another good material, but tends to shrink with exposure to water. While it may shrivel up, it usually remains intact. Kraton and other rubbers are nice, but are prone to loosen up with impact, and wear down quickly with abrasion and chemicals. Delrin and nylon are great, but tend to be low on abrasion resistance. Zytel is fiberglass-reinforced nylon. The phenolic laminates (often called micarta) are my favorites. Their mechanical properties are superb, and a number of colors are available. Canvas, Linen, and Paper-reinforced phenolics are all excellent, providing three different visual and tactile textures.
Fasteners – On full- and rabbetted-tang knives, you often find bolts, pins and tubes, and the squeeze-together cutler’s rivets. Bolts are very strong, pins and tubes are good if the glue-job was done properly, and the cutler’s rivets are the most suspect, due to frequent absence of good adhesive. Most of my hidden tangs are the rabbetted type, with the two slabs held together by bolts. Through-tangs, where a rectangular hole is cut through a block of material, and the handle is secured by a screwed-on or pinned-on buttcap or pommel, are good as well.
Adhesives – Epoxy is the industry standard. Surface-preparation is the key. Many knife handles (notably, many Randall handles) are held together entirely with glue.
Full-tang vs Hidden-tang
Full tangs are strong, simple to construct, heavy, and require a wider piece of steel to make a knife of the same size, compared with a hidden tang. Hidden tangs use less steel, are lighter weight, easier to balance forward for more chopping power, make more efficient use of overall length, and are easier to put a long, effective guard on for safety. A hidden tang would be my choice for backpacking. It gives the most cutting power and useful size with a minimum of weight and length. With a soldered-on guard and a phenolic-laminate handle, hidden-tang knives can be more than strong enough for any sensible use, including light hammering on wood or other soft materials, or being pounded on with a wooden mallet in order to drive the point through something. You are most likely to break the blade, not the handle. A hidden tang of this type is also sealed away from the elements, so moisture and rust are kept out.
Full tangs carry more weight, offer different balance options, and (for me at least) take less time to construct. They can be tapered, which reduces weight somewhat. I like their appearance, and they do well at inspiring confidence in customers, who often prefer them. They hide nothing, and if the slabs were to come off, the knife would be more functional than a hidden-tang with its handle missing. If you wish, the steel of the tang can protrude beyond the handle material, providing a more substantial pounding and smashing capability. (This does have some slight disadvantages, though.) It was a full-tang knife that inspired me to start making knives, and a full-tang knife is on my belt as I write this.
– Christopher T. Fischer