I’ve written about my first forge and my next steps in creating a homemade smithy and trying to forge my first blades. My third attempt is still pretty ugly and chock full of flaws, but it almost resembles a usable blade, and I added the new skill for this one of making a handle for the knife.
I started with a bar of steel from the “steel by the piece” bin at a box hardware store. I have no idea what the carbon content or composition of this steel is. I’d guess it’s somewhat higher quality than the rebar I used in my first two attempts but not nearly as good as steel you’d typically use to make quality knives. Whatever the quality, it’s what I started with.
I heated this up to a smushable temperature and began flattening and drawing the bar out into something that looked generally like a blade. I didn’t take process shots while forging, but in the photo below, you can see a form that looks like a knife, with a hint of a drop-point, a proper if un-lovely blade belly, and a bit of an ergonomic handle shape. It’s not pictured here, but there’s also a taper from the back of the blade to the front and a taper from the spine to what will be the cutting edge. And the blade is generally pretty flat where it should be, with the tang of fairly uniform thickness and no major bends or warps. There are some high and low spots due to careless hammering, and some of these will prove stubborn. This is a significant leap forward in the product of the first forging process from what I had done in my first two attempts to make a blade.
When making my first blades, I got the general blade shape and then quenched right away. I hadn’t learned yet about best practices for refining the blade.
When you bang on steel, you just really mess up its structure. Makes sense, right? The process of normalization helps fix that by giving the crystals in the structure a chance to realign. To normalize, you reheat your finished blade form back up to right around its critical temperature (which varies by steel, etc., but just trust that it’s an important temperature for bladesmithing somewhere around 1400 – 1500 degrees Fahrenheit) and then let it air cool back down to where it’s not glowing anymore. You repeat this three times, and the blade keeps its shape, but the structure of the metal becomes more stable than it was after all that hammering.
This time around, I had learned that after you normalize but before you quench, you create your final blade shape by grinding and sanding the blade. You want the blade to be petty close to its final shape (but not sharpened yet) when you’re done with this process. I don’t have a grinding wheel, so I used a belt sander and a bastard file with a homemade jig to try to smooth over uneven spots in the blade (and tang) and to create a consistent bevel angle on the blade. If you fully sharpen the blade at this phase, it’s likely to get messed up in the quench; common wisdom seems to be to get your cutting edge to about the width of a dime. In the photos below, you can see a rough grind that left the blade tip in a pretty weird shape, then a further grind that put a bit of a bevel on the blade and corrected the tip. The third photo shows the bevel on the cutting edge. You can see that I wasn’t able to get a consistent grind using my file, but there is at least a bevel. I’ve also drilled holes in the tang in these photos both for handle pins and to reduce weight a bit. There are lots of hammer imperfections still, including those stubborn ones on the blade.
After you’ve done the shaping, you can quench. Quenching is when you heat the blade back up to around its critical temperature and then cool it super fast by plunging it into a cooling fluid. The idea is to cool the blade from somewhere in the neighborhood of 1500 degrees to 800 or 900 degrees in under a second. Different quenching fluids are better for different types of steel, but for this blade, I used canola oil, heated up to about 130 degrees.
The purpose of quenching is to harden the steel. But with hardness comes brittleness, so you also want to temper the blade pretty quickly after you quench it. Tempering requires heating the steel up to a much lower and even heat, letting it cook for an hour or two, cooling, and repeating another time or two. For me, this meant putting some sand in an aluminum pie dish to help with keeping the temperature even, placing the blade on top of the sand, and cooking in my toaster oven at about 350 – 450 (I believe) for a couple of hours, two or three times. This process helps remove some of the brittleness of the blade without heating it up so much that you lose significant hardness.
With all of this done, you’re ready to begin refining the blade even further. I started with sandpaper, going from about 100 grit up to about 600 grit to smooth the metal out and sharpening the knife, poorly, with water stones of 400, 1000, 3000, and 8000 grits. I got the knife reasonably sharp in the end, but not as sharp as I really wanted. How much of this was my technique and how much was that this was unknown steel quality I can’t say, though I suspect my technique was a big part of it. I’ll know before too long, as I’ve got some quality 1095 steel for my next attempt.
Once I got the blade in as good a shape as I felt like I could within the bounds of my own patience, I turned my attention to the handle. This blade was looking decent enough that I was willing to learn this part of the craft. I had purchased a few sets of DymaLux knife scales and picked a walnut color for this knife, with silver colored pins to hold the scales in place. I cut my scales down to the approximate length of the handle. Since this is a wide handle, I didn’t need to take much else off the scales, which was lucky, since I don’t own a band saw. I attached one scale and drilled holes through the tang and through that scale to make pin holes in the scale. Then I lined up the other scale and drilled its pin holes to align with the others. Finally, I applied epoxy to everything, tapped the pins through, and clamped everything together to dry.
This left me with an awful rectangular handle. Once it was dry, I began sanding with my belt sander to cut the scales down to the right size and shape. Then I did a lot of work with sandpaper, starting with 80 grit and moving up through 600 to try to get a nice smooth, contoured shape on the handle. It’s not perfect, but I’m pleased with it on the whole. I put a few coats of boiled linseed oil on the handle to protect it and to bring out the color of the wood.
Finally, I wanted to work on the blade a little more. So I taped up the handle and did another cycle of sandpaper on the blade surfaces, working from about 200 grit up to 600, 1000, 1200, and 1500. I used a Dremel with a polishing brush and some polishing compound to try to buff out some of the scratches and give the blade a little more shine. And I re-sharpened the blade using my same water stones and a neat set of Spyderco ceramic sharpening stones I’ve had for years. It has a decent edge on it now, though still not quite as good as I’d really like. But as a first “real” knife made from start to finish by someone who doesn’t count himself especially good at detail work, I’ll take it, imperfections and all.
3 thoughts on “First Finished Knife”
I missed the first few posts about blacksmithing. This is wicked cool!