How I make a Knife Pt. 2

While the blade was normalizing, I went to work on the handle. I chose a piece of spalted maple I got from a trade a while back. Spalted maple is maple that has small lines of fungi running through it, discoloring the wood. The fungi has of course, died since the the wood was dried, leaving only the coloring. I cut off a block slightly longer than the width of my hand, drew a rough line over it for the handle shape, and cut it out.

Soon after taking this photo I recut it to a better shape.

I then took it to the belt grinder, using the slack section on a 36 grit belt, refining the shape and rounding and forming it.

Rough formed handle

I went for a “coke bottle” shape, which offers very good and comfortable grip, thinning around the forefinger and pinkie area, and thickening just outside those and in the palm.

The coke bottle shape gives a very nice grip

With the handle finished shaping, I began working on the blade, grinding the profile to how I like. I use the guidelines as only that, guidelines, permitting myself to grind extra here and there to improve it. I ground the false edge  (the little ridge on the back of the blade) first; my goal being the spine of the blade goes from the handle, hits the false edge, but subconsciously continues as the crease between bevel and false edge. The key to a good knife design is continuing and flowing lines throughout the knife.

I place the blade sideways in the clamp and grind with the angle grinder from above

I then begin grinding the bevels, using an angle grinder with a 120 grit flap disc. Most smiths would do it all on the belt grinder, but for me the angle grinder is faster, as I can bog down the belt grinder too easily due to a weak motor, which I need to upgrade. Here you can begin to see the design left by the rasp teeth.

The C-clamp on the blade is so I don’t grind too far and into the ricasso

I then grind around the ricasso and tang, and grind everything uniform on the belt grinder. Then I switched to a 220 belt on the grinder and sanded the blade. Because the blade was blackened, every scratch from the 36 grit belt showed up in black, so I knew exactly where I needed to grind.

I then began to bring the blade and handle together. I put the handle in the vise, blade side facing me, and drilled in a hole slightly longer than the length of the tang, and a little smaller in diameter. I then heated up the tang in the forge, and carefully pushed it into the hole. The heat burned away the wood directly in the way, smoking but not creating flame, as there was not enough oxygen inside the hole to start a fire. As the heat only burned away the wood directly in the way, and no more, the tang burned out a perfect fit for itself. At this point I also heated up the whole blade in the forge and normalized again, as the heat from grinding friction could create small stresses. The heat oxidized the blade and turned it black, which is handy for a reason I will explain in a minute.

Part of the design key is to always have the ricasso the same width as the immediately adjacent handle, creating a smooth transaction from handle to blade

I then began working on the bolster, which is a piece of metal between the handle and the blade, and acts as a transitioning piece. In this case I chose copper, as it is easy to work with and I have in plenty, besides being very beautiful when polished. I started with a thick (a little more than 1/4″ thick) sheet of copper, and cut out a square, and drilled it with a bit the same diameter as the thickness of the tang. I then used a round file to cut out the slot to the exact shape. I had to go slowly and carefully, just a little too big means a wobbly bolster, which I would have to throw away should I mess up.

I push with my right hand and put the palm of my left hand on the other end, to put pressure down on the copper

Every few seconds, I try to fit the tang inside, and note where it needs to be filed away more. Eventually I got a perfect fit.

Temporarily assembled knife

I used a miter saw to cut off the excess copper, then reassembled the knife and traced around the handle with a sharpie, and used an angle grinder to rough shape around that line.

Rough shaped bolster

I then finished it up to exact shape on the belt grinder.

Then it was a lot of sandpaper, until the bolster was 1500 grit, and used a polishing wheel on a dremel to polish the bolster.

Polishing the bolster, on a high speed dremel

With the bolster polished, it was time for heat treatment.

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