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After the previous article from Leap regarding putting a handle on a knife blank, and some ongoing discussions in the comments, I wondered if it was within my capacity to do likewise. I asked a lot of questions of the Glibertariat, trying to harvest knowledge for the project. The first big problem I saw was that the example from the original article was a single-edged hidden tang blade. Since I have heaps of utility knives, I am making something for a more artistic goal. Aesthetically, I like the shape of a double-edged blade. Structurally, I prefer a fully tang – which is where the shape of the handle and the shape of the metal within the handle are identical. Unfortunately, the unsharpened knife blank I found had a tang of a shape I didn’t like and would be too small to be comfortable in my oversized mitts.

So, I sank a lot of disposable income into buying tools and parts. In terms of cash outlay, it would have been cheaper to buy a knife. But part of that was because my toolbox was geared towards the problems I’ve had to deal with. But tools are a capital investment, and if I keep doing this as a hobby, the amortized costs would head towards negligable. But, that is neither here nor there. The question is, could I learn enough to make a decent piece?
First off, I discarded the idea of making the blade myself. That was just way too far out of my skill reach at the moment. So I’ll be trying to put a handle on the blank. This process stretched out over a couple of days in the evening after the day job.

Day 1 – The blank is here

While I technically started the project when I ordered the parts, but I couldn’t do anything until the parts arrived. The pieces that showed up in that first box were the blade blank proper, the handle scales and four Corby bolts. The blade blank is hardened high carbon steel, but not sharpened. This is good, because it’s easier to handle while working on it. Plus, without an edge, it’s not a dagger, it’s a letter opener. Thus this is not an elaborate confession to weapons possession. The handle scales are Resin Ivory, basically an imitation Ivory made of synthetic materials. So the only piece of hardware that might need elaboration are the Corboy bolts. Traditionally, handles would be held with solid pins. There are a lot of downsides to that, however. You either don’t have a mechanical lock, or you have to manually peen the ends. Corby bolts are one of several options that use threaded shafts to bridge two thicker ends. These provide a more secure connection, which is good for newbies like me. The trade-off is that the holes need to be coutnersunk. Luckily, I have a standing drill press, and know how to work with it.

So, after excitedly telling the Glibertariat that the parts were here, I set about assembling the remaining materials. Because the tang is smaller than my intended handle, I need to fill in the rest of the space around the tang on the same layer. If I was masochistic, I could try to cut out spaces in the resin ivory to rest the tang in. I’m not. I’ll be adding some spacers in which it is easier to cut the shape. The material I decided to use was leather. I have stores of leather scrap from various crafting projects. I picked some brown oil-tanned scraps and a bright red suede split. The oil-tanned leather I never got around to using before, as it was stiffer than I’d expected. The red pigskin suede I’d used to line my toolbox. Only the harder oil-tanned leathers would be cut to shape around the tang. The suede was too thin and elastic, and is there for decorative purposes.

Parts stacked and trimmed to size, I prepared to drill the holes. Since there were already holes in the tang, I decided to use that as my guide. Taped together to keep them from moving around, I brought the lot to my drill press. Resin ivory has an… interesting aroma when being worked. It wasn’t strong enough to drive me away, but something to note if you decide to use the material in one of your projects. On the plus side, it is easy to work. On the down side, it is easy to work. With one slip while drilling the last countersink, I suddenly had a three-sixteenths inch hole all the way through the scale instead of halfway through as intended. So, I was going to have a pin instead of a bolt holding that spot. Oh well, I’ll still have two bolts.

Holes drilled, it did my first test fit. It was a real pain to work corby bolts with one screwdriver. This is because they’re intended to be driven by two screwdrivers at once. Still, I got it together and it seemed to work. I chose not to do any more work that day, since it was getting late, and the only task I could do was trimming the oil-tanned leather.

Day 2 – The Epoxy

After I ordered the blank, I realized I’d ordered four Corby bolts for a blank with five holes. After some thought, I realized I didn’t want to have two countersinks on the holes by the base of the blade. That would seriously weaken the resin ivory. These holes are there for a bolster to be attached. I decided to pin them. I didn’t have copper pin stock, but that is easily rectified with a visit to the internet. My pin rod and epoxy arrived a day ahead of schedule, and one day after I started the project. So I set about getting ready to assemble. I trimmed the oil-tanned leather to shape with hobby knives I owned for other expensive passtimes *cough*Warhammer*cough*. Once I had these blanks, I did another test fit of the layers and tried to fit the pin rod through. Here I was reminded of the aforementioned elasticity of the suede. The drill bit didn’t punch a full eighth-inch hole through the material. So I got out my leather punch. It is basically a hole punch like those used for paper, only designed to put holes in leather. I punched out a set of larger holes in the suede to stop snagging things.

Despite using the holes in the tang as a guide for drilling, the pins didn’t fit, even without the suede. I am tempted to blame mystery causes, but the truth is, it’s my fault. My countersinks were not perfectly centered on the holes, so the corby bolts shifted the scales ever so slightly off. If you remember yesterday, The resin ivory is easy to work. A round file of small enough diameter shaved off enough resin to fit the pin stock through. There was a lot of grumbling through this stage. But it was better to find out these problems before I started with the epoxy. I was still within my margin of error for never having done this before. It could still be brought together. However, the dry-fitting told be something very important – I wanted to make sure I was in clothing I could afford to lose when I started working with the resin. The lack of a table-mounted vice meant the operation of the Corby bolts was awkward, even with two little screwdrivers. So the odds were, I’d spill on myself.

Having changed, cut two pins off the main pin stock, andassembled my stuff, I decided I hadn’t taken enough precautions. I grabbed a giant trash bag to use as a drop cloth, and a pair of resin-mixing gloves. Okay, they’re disposable nitrile kitchen gloves. Mixing up a quarter ounce each of resin and hardener, I began my assembly, spreading epoxy on before each layer was placed, and coating the pins. Suede is a very porous material, and soaked up epoxy into its structure. After hardening, it should be a composite material akin to fiberglass or carbon fiber rod, only with organic fibers. The oil-tanned leather is less porous, and didn’t soak in as much, but still absorbed enough to have a similar effect. When initially thinking about the process before any of the dry-fits, I wondered if I needed loc-tite, or similar thread glue. But the dry fits told me there was zero chance I wasn’t going to get epoxy in the threads of the Corby bolts. This is not an issue, since I want the handle as solid as I can get it.

Pins set, layers epoxied, I noticed a problem. The countersink that went all the way through resulted in the end separating, as it didn’t have the mechanical pressure of the other two bolts, and the leather is… squishy. Fortunately, I picked half hour epoxy, so I had time to grab some scrap plastic and a set of clamps. Fitting three clamps about the handle, I got everything back to the proper shape. Clamped up, I left it to cure overnight.

Day 3 – Daily Grind

I get home from the day job, decide to remove the clamps and peel off the plastic. Luckily, the plastic didn’t adhere to the epoxy, but the last clamp was stubborn about letting go. At first I thought I’d ripped the plastic and epoxy had seeped through. Nope, once I detatched it, the plastic was intact. But there was this big round dent. I was mortified, thinking I’d overtightened the clamp and crushed my way into the resin ivory. Finishing the plastic removal I inspected the damage. It was not so dire as my fears. I had so much epoxy that had been pressed out of the middle of the handle that it had pooled around the clamp and shaped to the bevel of the pad. This was why it was so difficult to get the clamp off. Relieved, I set about getting ready to drind down the pins and take off the excess epoxy. For this, I definately wanted a face mask. I don’t care whether or not California thinks it causes cancer, I just don’t want to be breathing that stuff in when I reduce it to dust.

And it occurs to me at that moment that while I do own a belt grinder, it was still in the box. So I went and opened the Amazon box. Unsurprisingly, there was another box inside, unbranded. So after disentangling this box from the Amazon box, I open it – and find another box inside. They had sent me a Matroyshka Doll in box form. Eventually, I find not more cardboard, but styrafoam. Prying it off, I unveiled a lovely piece of hardware, which I didn’t have a place for. it ended up on top of my table saw. (Fortunately, the sawblade retracts below the level of the table). Finding a breath mask and ear protection, I set about cleaning up the pins and bolts.

Grinder all set up, I learned a few things, some of which I already knew to some extent. First, when you abraid off material, what is left heats up. Second, copper is an excellent conductor of heat. So, if you were, for example, grinding down a copper Corby bolt and hand your finger on the other end, you’re going to feel it. Third, Resin Ivory grinds easily. Fourth, eoxy-impregnated leather does not. Fifth, a belt grinder is a versitile tool that can do wonders in the hands of a skilled user. Sixth, I am not skilled with a belt grinder. Seventh, grinding produces an epic crapload of dust. I was so glad I put on a respirator mask. My first grind was pretty rough.

I realized that the layout of one of the grinder components was preventing me from doing what I needed to in order to have the shape I was looking for. I needed to adjust the location of a guard behind the belt proper. Removing the operation interlock from the power switch I took the side of the machine off. There’s no one to flick the switch, but I was about to stick my hands inside it. I saw that this white enamelled metal piece was just being held in with a paur of bolts which an allen key could operate. After loosening one and accidentally tighening the other, I got both loose and started to lower the guard. At which point I found that it was not white. It was dark blue. There was just so much resin dust coating the surface that I could no longer tell.

The guard lowered slightly, I got more shape into the handle. I noticed that the composite leather material was by far the harder one to grind. The resin ivory essentially disappeared when subjected to the belt, so all of the resistance preventing me from absolutely wrecking the handle came from that leather/epoxy core. So what had been intended as a decorative element became a key structural one. I’m okay with that. Especially since I’d been expecting the resin ivory to be stronger. After the second grind, it was pretty good. I did have a problem. The respirator mask so essential to not breathing in the particulates also impeded the airflow to my lungs. So, I had to step away from the room and take the mask off.

Part of me went, that is a pretty good shape for a first ever attempt. But there was another opinion rattling around in my head. It said there were things I could fix, even with my skill level. Flaws that I could remove. So, I got back in there and went for a third grind. I cleaned up a lot of the protests I had, making more refined handle than I’d had. It was still clunky and crude, and I did some hand filing and sanding to deal with areas where the grinder would do more harm than good. I even tried to polish it with beeswax. Only to very quickly discover I had no idea what I was doing. I sanded the wax off and went back to refining it with abrasives.

Finally, I had something that felt good in my hand. It wouldn’t win any beauty contests, but the handle is in one piece, there are no massive faults, and it will hold up. There was just one problem. There is no edge on the thing.

It will not cut.