Blacksmithing Odds and Ends

A couple of weeks ago, I decided to try learning some different skills in blacksmithing. I had seen videos on how to make a leaf and a suggestion that making a lot of leaves was good practice for hammer work and a couple of key techniques. So I made a couple of leaves, though the leaf broke off of the stem for one of them. This past weekend, I made another, which was somehow a regression from my first (I used thicker and I think maybe harder round stock and had a devil of a time getting it shaped). Only my first/best leaf is pictured below.

The same weekend I started trying leaves, I heated up some 1095 steel I had bought and wanted to try out. Previously, I had used only the sort of dubious steel (including rebar) you can get at a box hardware store. I was curious whether this steel with a better “pedigree” might forge differently. Mostly what I learned is that I don’t have the right tongs for working with steel that comes in long, flat bar form. There are special sorts of tongs that make this stock easier to work with. So I spent a lot of time bruising my tong hand to try to hold my work piece in the tongs by brute force. This made it harder to work the steel.

I did on that first day pound out what looked like a nice dagger (if very wide) or sword (if very short) point, roughly. I put it down when I ran out of propane. This weekend, I picked it back up and decided to tinker with it some more. My son had been talking about making spearheads, and I thought I may as well try to thin this one out into more of a spearhead shape. Doing so gave me fits. You can see that the notches that define the posterior end of the spear blade are way out of alignment. I can correct that later somehow. The main thing I struggled with was narrowing and drawing out the piece. I wanted to keep a bit of curve to the edges, but I haven’t figured out a good technique for that and wound up having one edge curved and then flattening it while trying to curve the other edge. So I need to figure out how to resolve that. The next step, which I may not be able to manage with this bar, is to make a big rounded triangle of the butt end that I can then forge into a conical socket to stick a handle into securely. I don’t know if I’ll get that far, honestly. Pictures, at any rate:

Also this weekend, I tried dressing a hammer using this guide. That blacksmith has been making videos since he was pretty young, and he strikes me as sort of a prodigy. He has a pretty cool hammer that’s probably way more than I could ever justify spending on one. It has a flat face and a rounded face, and though technique is as important as tool, it does look like it’d be nicer to strike with. His video purports to teach you how to turn a $7 hammer into one as good as a $200 hammer. This sounded appealing!

I started with the cheap 3-pound, 16-inch Pittsburgh sledge hammer he proposed and followed his tips as best as I could to fix up the hammer faces. The rounded face definitely leaves less severe hammer marks. Probably I need to work on technique a lot more than I do making a fancy hammer, but this was kind of a neat grinding project anyway.

Finally, I came into some big long spikes. I have no idea what they’re for. They were very rusty and dirty, and I decided to clean one up this weekend by grinding it down. I’ll try some rust-busting compound on the other one first to compare how well it does. I burned through the better part of two grinding wheels to get this one shiny and I’ll bet that using some chemicals to get the worst of the rust off first would save me grinding. I wonder if one of these might be better for a spear, given that there’s plenty of material to forge the head out of and then a nick thick bunch of stock to forge the conic socket from. I feel like I could get at least two spearheads out of these (maybe three from the one without a hole in it).

First Finished Knife

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.

Forge #2, with Anvil, Stand, and First Blade Attempts

A while back, I wrote about how I built a homemade forge. That effort didn’t go the best, other than helping me learn a bit about the process of building a forge. After that one, I decided to buy a cheap propane forge in hopes that it’d help me reach and maintain adequate temperatures for forging steel. It took a little assembly and required that I get over the terror that I would somehow blow myself and my house up in the process of learning how to use this new style of valve for the hose that connects to the tank, but I did ultimately manage not to blow anything up. I also bought a 30kg (about 66 pounds) steel anvil, which I thought would be a big improvement over the small flat surface on the cast iron vise I had used previously as a striking surface.

The anvil needed a lot of work in order to be ready to really use. The blue paint on it is applied to help prevent rust while the anvil sits in storage. And boy is it a pain to get rid of. The job did give me a good excuse to buy an angle grinder. Using a combination of grinding, wire brush, and flap wheels for grinding and polishing, I was able to get rid of the paint and polish the horn to a reasonable smoothness. Then I applied some acetone to clean, some Loctite rust neutralizer, and finally a nice coat of WD-40 to finish preparing the anvil. It turned sort of a lovely purple/black color. This is a small anvil, believe it or not. Anvils come in lots of sizes, even into the hundreds of pounds. Even this little one was not exactly cheap, and the bigger you go, the more expensive they tend to be. One day, I’d love to have a bigger anvil of a couple of hundred pounds, but this is a big upgrade already from what I used in my first attempt to move metal. I followed this tutorial to “dress” the anvil.

Once you’ve got an anvil, you need to mount it on a steady, pretty heavy surface. Lots of people use tree stumps. I cut some 8-foot 4x4s to size, then glued together three on a side to give me about 10.5 inches of top surface, which is plenty big for my anvil’s footprint. Then I cut some threaded bar to size, drilled 12 holes all the way through the sides of the stand, and used nuts and washers in countersunk holes to pull the 4x4s together more tightly. I did some chiseling and sanding to get the stand to be fairly level, and then I added thick, shimmed plywood to top and bottom to reduce any wobble. It’s not perfectly level, but it does the trick. I used this tutorial with some slight modifications (and a lot less precision) to make the stand.

I don’t have a proper workshop. Instead, I have a cluttered garage in which I store tools and movable work tables, and then I pull a car out of the garage to make a workspace or just drag all my materials and tools out into the driveway to do my work. Setup and tear-down are annoying.

In the first photo below, you can see that I’ve traced the anvil base on top of the stand and applied some silicone caulk to the parts of the stand that the anvil base will sit on. The intent here is to help dampen the ringing sound of the anvil. That ringing is pretty once or twice, but when you’re striking steel again and again, it becomes pretty unpleasant to listen to. You can also see that I’ve drilled pilot holes for some big bolts to go through. I cut some steel bar stock to approximate size, drilled holes in it, and used the pieces as mounting plates to affix the anvil firmly to the base. It’s pretty solid, and the addition of this metal helps dampen the ringing sound further. I picked this general technique from some tutorial, but I’ve lost the link.

That’s my new setup, which I put together in late January. I’ve forged three things since, and my son has forged two. My first was a really rough blade form that I ground and polished until it looked vaguely like a butter knife. It’s a real ugly duckling, which I’ll document visually here for the sake of showing progress. The rough form doesn’t look too bad, but look at all those hammer marks and scale. And then look how much I ground off to try to smooth those out and sharpen the thing. I didn’t know yet how to add a bevel or how to properly grind (I’m still learning).

For the second, I worked to try to make a better blade form in the forging process rather than in the grinding process. Common wisdom among blade smiths seems to be that you’ll spend a lot more time grinding a blade to shape than you will forging it to shape, so it’s better to get your blade as close to its final shape in the forge as you can before doing any post-forge grinding and shaping work.. So I made a much better blade form on my second try, though it was still very rough and was flat, with no blade tapering. I improved upon that technique in my third try, which I’ll post about separately, but here are a few shots from that second try.

Again, there are lots of hammer marks, and the blade shape is ugly (and the tip poorly done), but it’s a step forward. The third blade I worked on is much closer to being a real, usable knife. Stay tuned for that post.

Forge #1

Over the last few years, my son and I have watched a show off and on titled Forged with Fire. It’s a competitive blacksmithing show that really made us both want to go fire up some metal and bang on it. But blacksmithing seemed difficult, intimidating. Even if I could get all the equipment an figure out how to flatten some metal, could I really make anything useful? I put the thought aside for a while.

In the last quarter or so of this year, the urge struck me again and I decided maybe I could make a simple forge using things I had on hand. There’s a type of forge called a JABOD (just a box of dirt) that will do in a pinch. At the most basic level, what you need to build a forge is a chamber to hold some fuel and air pumped into that chamber to make the fire burn hotter. Steel needs to heat to something like 1200 Fahrenheit before it’ll be hot enough to shape.

Well, I had an old grill that seemed like it’d make an ok forge chassis. And I have a shop-vac to blow air. All I needed was some way to heat-proof the grill a bit and pipe air into it to stoke the flames. I was going to use lump charcoal (not briquettes) because it seemed the easiest way into the hobby (anthracite coal would’ve been another option).

Now, the floor of my grill was not solid or sturdy. It was basically a sloping grease trap made of thin metal. It would need to be reinforced somehow. I opted for cutting some plywood to provide a level floor, figuring that putting refractory material over top of the wood would protect it. I didn’t get a good photo of the grill before recycling it, but here it is with the piece of plywood I would cut to size.

Here I’ve begun ripping off the dials and pipes and wires and such that I wouldn’t need.

The board, cut to size and braced (it’s thin plywood):

Note the little notch on the end. I put it there to accommodate the pipe flange attaching an air pipe to the grill (stay tuned for that).

Here’s the new plumbing I planned to add to the grill to bring air from the shop-vac to the fire bowl inside the forge. I didn’t wind up using all the pieces, as I tinkered with my original design as I went.

I had to drill some holes in the side of the grill to fit the flange. Here you can see the holes, and then the flange installed, with a pipe screwed into it. Don’t mind the wire — I got rid of that later.

Now I had something that was beginning to look like the skeleton of a forge, with the leveling board inserted and the plumbing installed. You can see the hole on the left-hand wall and the light shining through the knob holes on the front surface. I would need to patch these up somehow or else I’d have lots of fire shooting out of them. I didn’t think that simply mashing refractory material into the holes would work. It’d likely fall out before it could harden, and at any rate, it’d be a pretty thin barrier.

Remember that box of miscellaneous grill parts? I thought there might be something useful in it. Indeed there was! I got out my tin snips and cut out little patches I could wedge in front of the holes. Some needed a little bending to fit around curves in the grill wall’s surface. These were not perfect, but I hoped they’d give the refractory material something more to cling to.

I’ve mentioned refractory material a few times and am aware that I haven’t defined it. I take its purpose to be both serving as a barrier between meltable/burnable parts of the forge an to keep some of the heat in the forge. You can get fire bricks for this, or you can buy refractory concrete. If you’re building a JABOD forge, you can use dirt or clay for refractory material (or maybe you just don’t need proper refractory material because the worst you’ll do is cook some dirt, provided you’ve picked any rocks out of it). I didn’t want to dig a bunch of holes in my yard to get dirt, but I did want to go the cheap route, so I got some plain old cheap cat litter and some playground sand. For best results, you want to powder the litter. What you really want out of it is the clay (so you don’t want the stuff with crystals in it). Mix that with sand, ashes if you have them (they’re good insulating material), and water and you can make sort of a mud you can use to make your forge more heat resistant. This was a real pain. I stated with a mallet for pounding clay (breathing a lot in while I pounded) and graduated to a cheap blender, which broke after doing a few pitchers full. I had loads more sand, and I had plenty of ash from our fire pit, but I got tired of pounding the litter, so I had less refractory material than I really wanted.

I had my refractory material now an needed to try to make a fire bowl and some horizontal surface around it. I just made this part up and had no idea whether it’d work or not. It turned out better than I had initially figured it might. I first spread the goop over the plywood and around the pipe, leaving sort of a hollow around the tip of the pipe. I wanted a nicer looking fire bowl, so I used a real bowl to shape the hole. Once I had the basic shape, I wanted to build the flat, raised surface out farther and higher. You can see how the bowl looks shallower in one picture and deeper in another — in the latter, I had built material up to the rim of the bowl. I built a wood fire on top of the material to try to help it dry and cure. It worked only ok. If you look down in the bowl in some of these pictures, you can see the opening for the air input pipe, which delivers air right to the center of the bottom of the bowl.

With that settled, now I needed to rig up my shop-vac to be able to blow air into the forge body. I knew going in that the shop-vac’s hose would not naturally fit the pipe I had selected. I also harbored a hope that I could 3D print an adapter. So I learned a little bit about design specifications for threaded pipes, etc., and I did the math and modeling required to make an adapter that would thread onto my pipe at one end and onto my shop-vac’s hose at the other. Problem is, I’m not great at math. Even though I felt as if I had honored the spec perfectly, my plastic pipe fitting was just a hair too large for the pipe, which would sort of thread into the adapter but would not do so perfectly. It seemed close enough for a first-run. I might lose some air given the looser connection to the pipe (the connection to the shop-vac was pretty good), but I didn’t think I’d lose too much.

Now the thing was assembled. Time to fire it up! One thing I learned was that I did not need to worry about losing air through my adapter. I had more than enough air and, alas, a shop-vac with only “on” and “off” settings. I loaded the fire bowl up with some chunks of lump charcoal (basically wood burned in a low-oxygen environment) and some newspaper and lit it on fire. The shop-vac proved too much for the small lumps of charcoal. It would get them pretty hot and then blow them out of my fire bowl. I kept the grill’s lid down for some of this time to try to keep fuel in the forge, but the air was too much and I wound up with a rain of sparks and embers flying out of holes in the back and sides of the forge.

The fire did get hot enough to get a little dark red glow on my steel — you really want a bright orange maybe even tending toward yellow — but battling with the fuel and the airflow made it hard to keep the temperature up to anywhere approaching where it needed to be. I suspect that coal would’ve done better. After heating and trying to shape a piece of rebar a little bit, I finally gave up. It was clear that I wasn’t going to make a full success of the venture. Coals started tumbling/shooting out of the bottom of the grill, which indicated that my wood floor and the refractory material coating it had not held up to the fire. This is when I called it quits. My goal had been to move some metal, and I did accomplish that, but what I had in the end was a very slightly smushed piece of rebar.

Here’s the state of the forge after all of this effort:

The hole at the bottom of the bowl has enlarged, and indeed flames burned through the board underneath and chewed away at the refractory material too. You can see here some of the smaller lumps that my larger lumps of charcoal turned into. At top left, you can also see some lump near-charcoal I inadvertently made as part of this whole process while using a little hunk of wood to prop the forge lid open a little.

Naturally, after all of that, I failed to snap a photo of the smushed rebar, and it’s been a week or two. The result is sufficiently sad that it’s not worth showing it off anyway.

Still, I knew precious little about blacksmithing or forge-making when I started this enterprise. In the end, I made a functioning-ish forge and felt at times while building the thing as if I was in an A-Team montage. I’m pleased with this outcome. And I still want to make something that resembles a blade. So I bought an inexpensive forge that will work with a standard propane tank. Just today, I fired that sucker up, and I did get a better outcome (though still a pretty sad one). I’ll post about that separately.