Frame Handled Knives

I’m currently working on a new dagger project, as I had very good results with the last one. For this one I really wanted to use some ironwood scales, but I only have some thick enough for full tang (where the wood sandwiches the tang rather than the tang is inserted into it, which would be a stick tang). So for this project I’m trying for the first time a frame handled construction.

A frame handle construction is where you have a blade with a stick tang. Around this stick tang is assembled a metal case, in my case, copper, essentially transforming it into a full tang. On top and bottom of this, the tang is sandwiched with wood. This way you have the appearance of a full tang, yet before assembling the blade you can slide on a crossguard, which you cannot do with a normal full tang knife (due to the pommel normally being wider in diameter than the shoulder for the guard).

View this post on Instagram

A post shared by Caleb Harris (@covenantmfg)

Cocobolo and Maple Field Knife

The bolster of the original handle broke soon after assembly, and I wasn’t happy with the repair job I did, so I destroyed the old handle and replaced it, this time in cocobolo with a curly maple bolster, using the ricasso for a finger choil. The blade was forged from 5160, with forge scale left on. I’m considering removing it but leaving the texture.

Lucky

This was a project in trade for a friend, for a variety of woods and some leaf spring steel. T’was also her birthday very soon so I spent some extra time on it, something I need to focus on doing more with /all/ my knives, not just this sort.

So-called “Lucky” because I had several instances in which things had about a 50-50 chance of going horribly wrong, but in each case they worked up perfectly. When I was fitting the tang to the wood, I drilled all the way through it thinking the tang would be that long. In fact, because of the thick guard, It was shy of the edge of the pommel by about half a centimeter. I would need about half a centimeter further if I wanted to peen it over. This left me with a gaping hole in the pommel. The way I fixed this was by inlaying some turquoise into the pommel, very carefully carving out a depression around the hole with a dremel, and using epoxy and the end of the tang to support the stone. It worked perfectly. A bigger problem that scared me far more was when I was fitting the pin. The drill bit was too aggressive, and chipped the wood around the pin’s hole. The chip was too deep to grind down to. I nearly had to throw it away and restart right then, but managed to find the tiny splinter that had been thrown off by the drill. With a bit of epoxy it fit perfectly back into place, without a trace where the seam was.

The last bit of luck was with the heat treat. This blade is very thick, and so retains heat very long. When I quenched it in oil, only the steel near the tip hardened, and not the inside of the curve. I tried the quench again, with the same result. I tried it once more at a different angle and again it failed. My guess as to what was happening is the tip of the blade cooled and transferred the heat to the oil, heating the oil too much to harden the next section of steel. Whatever happened, I needed a more aggressive quench. I decided on the risky proposition of warm water. Water usually cools the steel too fast, putting a lot of stress of the steel and one time out of two will fracture it. If it cracked, I would have to throw it away and start the blade again. It went perfectly, quenched the edge, counted to three, took out of the water, waited a second, and repeated. Once the spine had lost color I cooled it fully. I took this photo just after quenching. The lighter area is hardened steel.

A perfect quench line. The darker area remains soft, while the lighter is very hard

All in all this knife was very fun to work with. The steel was forged from a rasp which belonged to the customer’s dad, which he had originally got when he was a kid. The guard is wrought iron, a type of pre-bessemer iron which is characterized by many slag inclusions, which show up with a light etch in acid. I used a brass spacer, brass and steel mosaic pin, rosewood from the customer, and turquoise inlay in the pommel.

The Southern Gentleman

This blade I forged several months ago but hadn’t got around to finishing, due to my being out of sharp drill bits. Recently I found out an efficient way to re sharpen them and so set about to finish it. The morning of the day I began work however, I went on an Art of Manliness article reading spree, which resulted in the unique finish of this knife. The style is called Brut de Forge, where many rough forged parts are left in instead of ground. This gives Brut de Forge blades and extremely tough and rustic look, which is enhanced when I combined it with the tough shape and thick, heavy steel, forged from a farriers rasp. The incredibly beautiful ironwood and brass pins balances this out, in a very smooth and refined finish. This combined tough and manly with comfortable, smooth and polite, all ideals that manifest themselves in the art of manliness, and especially the ideal of the “southern gentleman”, hence the name.

 

Physics of Anvils

When looking for an anvil, we’re told a good trick to test if an anvil is good quality or not is the bounce test; let a hammer drop onto the face of the anvil using only it’s weight to push down and your hands just to stead the hammer. If it bounces only once or twice, it’s bad quality. If it bounces six or more times before coming to rest, it’s very good. But why is that? What makes an anvil good or bad and how does the above test reveal it?

Simply stated, a “bad” anvil will form the workpiece very little per given force in a hammer blow, whereas a “good” anvil affects the workpiece much more for the same force. So this is how it all works.

When you drop a hammer onto the anvil face, kinetic energy (whenever I use the term energy in this post, it will refer to kinetic energy) is transferred from the hammer to the anvil, and from the anvil deflected right back into the hammer. So why doesn’t the hammer bounce back up with the same speed it went down with? Why does it eventually stop bouncing? (remember nothing stops moving unless something, well, stops it from moving)

Let me explain elastic and inelastic collisions real quick. An example of an elastic collision are two hard steel balls, of equal mass and speed, hitting each other in a zero-gravity environment. Ball A is going five MPH to the right. Ball B is going five MPH to the left. They hit dead on. What happens? They bounce apart. Why? Ball A has transferred it’s kinetic energy to ball B, and vice versa, so after the collision ball A is going five MPH left, and ball B is going five MPH right.

An inelastic collision is where you have two balls of playdough in the same situation as above, striking each other dead on. What happens? They stick and flatten. What happened? Because the molecules were not rigid in relation to each other (the playdough is softer) the kinetic energy is used to expand the playdough outwards. Kinetic energy has to go somewhere, and as it cannot go as it had in the direction it was going, it is used to expand the playdough outwards, not into the other ball. The steel balls would do the same, but the force is not great enough to move the molecules in relation to each other, so it is transferred to the other ball.

So, going back to dropping the hammer on the anvil. If the anvil face is soft, (inelastic) the energy from the hammer is transferred into the hammer face, and then outwards and downwards, pushing the molecules away, into a dent. If the anvil face is hard (elastic) the energy cannot be used to move the steel molecules apart from each other (bonds are too strong), so it goes right back up into the hammer, pushing it back. Because no material we have is perfectly elastic (which would mean the molecules do not move in relation to each other at all, no material we know of has this property) some is used to move the molecules in relation to each other, and the rest goes right back into the hammer. Each time the hammer bounces a little more is lost until there is no more energy to keep it moving. If both the hammer and the anvil are hard, the hammer will fly back up with the same speed it had going down, which is why as a blacksmith you must be careful not to miss the workpiece.

So finally we can get to how this all relates to forging. For ideal forging, we want as much energy as we can to go into the workpiece, into moving the molecules in relation to each other. If the workpiece is hard, most of the energy is transferred from hammer, to workpiece, to anvil, and back to hammer with minimal amounts going into the workpiece. The ideal workpiece is inelastic. How do we make it harder? By heating it up so the molecules move easier in relation to each other. With a good hammer and anvil, the energy is transferred from the hammer into the workpiece. About half of the energy goes into moving the workpiece molecules, flattening it, and from there it spreads out from molecule to molecules until the effect is invisible. The other half of the energy is transferred through the workpiece to the anvil. Maybe half, but more like a third of that energy goes into moving the anvil molecules (but because the workpiece has spread the energy over such a large surface on the anvil, the effect is barely noticeable), then the rest goes right back up into the workpiece. Half of /that/ energy deforms the workpiece some more, while the remainder goes back into the hammer, pushing it upwards with just enough force not to shoot into the smith’s face, but enough to raise it so the smith doesn’t need to do any work to lift the hammer. Then the process repeats.

Perfectionism

In the making of both knives I had most of the same equipment, and all the same skills (I knew what to do and how to do it); the knife on the right lacked the perfectionist mindset

One of the hardest and most daunting things I’ve learned, and am learning, is perfectionism in my work. When I started out, my goal was to “make knives”, which I accomplished easily. I did the bare minimum in accomplishing that goal, in that I only made what could barely be defined as a knife. My knives weren’t beautiful knives, they weren’t even good knives. They were functional knives, but that was it. A year ago, I went on a trip to Europe and took some knives with me. I visited several bladesmiths and asked them to critique my work, and the main thing throughout was I needed to perfect each aspect of every step before moving on to the next step. If I made a mistake I could not fix, I had to learn to throw it away and start again.

This is true, and learning to accept that you can’t fix it and so throw it away is very important. At the time I had the skills to make a good knife, I just lacked the patience and perfectionism. I’m not naturally a perfectionist and so I had to force myself to make each step perfect and have the perfectionist mindset throughout the entire process. “It’s good enough” became a crime.

Many people recommend, when you learn something, just do it over and over and make a whole bunch of whatever it is. At first, do so. This is giving you the muscle memory and basic intellect as to how to do the things. But only doing this, your hundredth knife is not sellable. Why not? It’s not flawless. It’s useful. But it’s not perfect. Once you feel you know how to forge, you know how to grind, you know how to peen, work wood, heat treat, and so on, start your next knife slowly. Take a month to do it if you have to. But when you start, make sure each step is done to the best of your abilities. When you forge out the blade, is it too thin? Throw it away. Is there a deep forge mark? Throw it away. When you grind the blade, if you grind too thin, fix it or throw it away. If the ricasso is not lined up perfectly on both sides, take a week to fix it. If you ground a divet too deep, throw it away. It gets harder after the blade is near finished, and after the knife is assembled. Its easy to make a mark, to cut the wood too far, to skip over sanding a barely visible mark out. Don’t let it happen. Make a mental checklist before you move on to a next step, some knifemakers even have a real checklist.

It’s daunting and touch, forcing yourself to make each step perfect, but one thing I wasn’t told is that it will become easier with time. It really does. After you force yourself to perfect the knives, and you make a few that way, finishing it becomes habit and it is no longer daunting. You can finish a knife quickly, as quick as before, but it’s still perfect. Habit makes perfectionism a joy, rather than a drudgery. Get through the initial perfectionism stage and it’s smooth sailing from there.

Even Forging

One of the main things with handforged knives that makes it look good, is even forging. If forge marks are still left in the blade after grinding, it really looks horrible. So a smith either has to grind the entire surface down to depth of each hammer divet, or can just initially forge the surface evenly and carefully. There are several tricks to help reduce the amount of divets you make while forging, but mainly it’s caution and practice.

First, make sure the anvil is at the right height. If it’s too high, the hammer will strike with the bottom edge, or the “chin” of the hammer hitting. If it’s too low, it will be the “forehead” or the top edge of the hammer that hits. To find the correct height, stand erect with hands by your sides, holding the hammer at a 90 degree angle to your body, and mark on the wall or a board exactly where the height of the hammer face is, and stack up the anvil to that height. This makes it so the hammer face is parallel to the face of the anvil, reducing deep marks significantly.

Second, make sure you have a good, firm grip on the hammer. When you grab it, wrap your pinkie finger first then follow the other fingers one by one. Do this until you get used to forging. Before beginning forging, hold the hammer firmly but comfortably, and hold it out directly in front of you. Adjust your grip until the face is facing neither right nor left.

Another tip is using a file or grinder of some sort, very slightly round the hammer so the face is slightly convex, so in case you do hit sideways, it won’t make as deep a mark as a sharp edged hammer would.

The last tip for even forging, is doing light taps at first until you see the workpiece deforming easily, with no evidence of one or the other hammer edge hitting. Once you have that down, give gradually harder and harder strikes, letting off a bit if you start to hit edge first. When starting out forging it feels and acts like writing with your non-dominant hand, you’ll gain muscle memory quickly and forging evenly will take no mental effort at all.

Instagram for Craftsmen

Instagram is often unthought of or overlooked by craftsmen, but is very proficient at getting your name and work out there and in common knowledge. The biggest two pluses for craftsmen are these: one, that it operates primarily on photos, and two, it’s incredibly easy to immediately upload photos from your phone and post them. This means you can take and upload pictures as you work on a project, without slowing down your work. And so, followers pretty much see the entire process from start to finish, so they get the inside scoop on both how much work it is, and how the object (in my case knives) is really built. People are interested in learning how things work, and so seeing the steel being forged, seeing the blade being ground, sanded, sharpened, the wood cut and formed, and so on really draws them in, and they can see, through the process of its making, exactly what the quality is. They can also see when a new knife is finished, and can make an offer on it. When this happens, and they get the knife, they will post a photo of it to their followers, which increases my following. From one sale to a knife enthusiast, fifty of his followers followed me, and many of those gave offers on my knives.

Also, many other types of craftsmen, with related trades, can interact with you. For example, I follow a lot of leather workers and woodworkers, and a lot of both follow me. The trades overlap, so everyone has at least a basic understanding of how the other craft works, as well as a use for it. Leather workers and woodworkers both have a need for good custom knives, and knifemakers need leather sheaths and handle woods. Perfectly set up for trades, and once a trade is made, both people post photos of what they got, and so both get a follower increase.

How I make a Knife, Pt. 4

Once the epoxy had cured, I clipped off as much of the protruding pin as I could with wire cutters then used the belt grinder to grind it flush with the wood.

I then wrapped the entire knife tightly with Saran wrap, and wrapped electrical around that to hold it in place. This was to keep the knife from getting wet.

The Saran wrap and tape keeps the blade from getting wet, which could ruin the wood at this stage

I took the leather and soaked it in water, making sure it was thoroughly wet inside and out. Leather is interesting that when dry, retains it’s shape, but when wet, becomes malleable and easily formable. I folded the leather over the knife, which due to the Saran wrap kept dry, and pressed the leather over the blade and the front of the handle using several wood boards and clamps.

The boards press the leather down on the blade, and due to the angle pinch the excess around the handle together to form a snug cocoon.

I left it to dry overnight. This type of sheath not only covers the blade, but part of the handle as well, so the knife stays securely in the sheath with active movement, yet is easy to remove when you want it.

The next day, I removed the knife from the sheath and took of the Saran wrap, and put some tape around the bolster to protect it, and began hand sanding the handle. The tape kept the sandpaper from marking the bolster should I accidentally touch it.

The tape protects the bolster from sandpaper

I put the blade in the vise, using wooden jaws so as not to mark it, and sanded the blade well, starting with 320 grit and moving up to 1500. When sanding the blade, I use a flat stick so I can get flat and even pressure, but for the handle I use my fingers, which one must note are perfect for the job, as the handle has many curves and is round. After sanding the blade to 320, I wiped the blade in a diluted cedarwood oil mix, cleaned it off, sanded to 400, wiped again, and so on. This is so I can well saturate the surface of the wood without drenching it; on many woods if I wait until I get to 1500,  the oil doesn’t sink in using the sandpaper scratches.

Once I was done sanding, I placed a few bits of beeswax on the handle and used a heat gun to melt them over the blade, and then used scrap leather to rub it in, both sealing the wood and simultaneously polishing it.

Now the beauty of the wood is shown

With the knife completely finished save for sharpening, I returned again to the sheath.  I used the slack section of the belt grinder to grind flush the edges.

I used the grinder to perfectly true up the edges

With the edges of the leather true, I opened the sheath up, placed in the knife, and used a pencil to make a guideline along the edge of the blade onto the leather. I then dabbed in a generous amount of epoxy on the outside of this line, from throat (where the blade enters the sheath) to tip.

I make sure not to go over the line, as that is where the blade will be

I then used a number of bricks to press the edges together, and waited for it to dry. While I waited, I began preparing the rivets for the sheath. Leather sheaths are generally held by rivets or by thread, and as I did not have the right thread and also quite bad skills at sewing, I went with rivets. I cut off a long section of copper wire, and placed it end up in the clamp, about half a centimeter protruding, using one wooden jaw and one steel jaw. The wood jaw squished around the wire, holding it on all sides, so it would be less likely to bend over one way or another. I used the back of a ball peen hammer, and lightly began tapping, using the weight of the hammer rather than exerting any force myself. A mis-strike bends the wire over, sometimes too much, so I have to clip the end off and start again. Using the convex side of the hammer mushrooms the copper out, into a nail head shape.

View this post on Instagram

A post shared by Caleb Harris (@covenantmfg)

I then clip off the excess wire, so the rod of the “nail” is a little more than a centimeter long. Epoxy hardens relatively quickly, so by the time I was done with the six rivets, it had cured. I drilled holes in possible stress points in the leather, at the tip, top of each side, and evenly in between. I put a rivet into a hole, and the sheath on the vise anvil, rivet head up. Then I used the same technique as I had earlier, (called peening) to mushroom the ends of the rivets into flat heads, firmly holding both sides of leather together. This video shows the full work of the peening. https://instagram.com/p/0mDFLzkPW1/

Once all the rivets were in place and peened, I used a leather conditioner to clean and color the leather.

Then for the final step, I began sharpening. First step in sharpening is always establishing the edge, grinding down both sides until they meet. All knives have two bevels, the secondary bevel, which stretches from or nearly from the spine, until almost to the cutting edge. The primary bevel goes from the end of the secondary bevel to the very edge of the knife, the part that makes first contact when cutting.

In the far right diagram, the primary bevel are the two slopes that start at the point, and go until a corner. The secondary bevel is corner where the primary bevel ends, and extends back until the spine of the knife. In an almost completed but not yet sharpened knife, there is the secondary bevel, but no primary bevel, it’s just a flat surface

In establishing the edge, I’m making the two edges meet in the center, using a coarse stone, so I use a vigorous back and forth motion, shown here. https://instagram.com/p/0mFLtPkPaX/

Establishing the bevel is just making the two sides meet and eliminating the surface that is 90 degrees to the blade. I always sharpen with the knife raised above the stone at about 20 degrees, or less if I can. Once the bevel is established, I hone the blade, making sure there is a very sharp and exact corner. This is by single motions, drawing the blade from tip to heel (end of the cutting edge) five times, running the edge along wood to knock off any tiny bits of steel (burrs) left on the edge, then flipping the blade over and drawing the blade from tip to heel five more times, and de-burr it again. Then I switch to a finer stone and repeat. The trick to making the blade razor sharp (literally), is keeping the blade at the same angle throughout, so the edge is not rounded over. It’s a lot harder than it sounds.

After a quick cleaning, the knife is now completed.

Finis!

 

How I make a Knife, Pt. 3

A good knife needs to be able to be sharp, to not dull after little use, and to not break under pressure. By using heating and cooling methods, I can manipulate the physical properties of the steel to meet these standards. First what I need to do, is harden the steel, so it can be used many times without dulling. To do this, I heated up the blade in the forge until it was a cherry red, the point at which steel, when touched against a magnet, does not stick. Once the entire blade was up to this temperature, I plunged, or quenched, the blade in motor oil. https://instagram.com/p/0eOm8jkPUs/

When the blade is heated to that temperature, the iron atoms switch formation from small closed cube formations to larger open cube formations, allow carbon atoms, which had been floating around between the cubes, to float /inside/ the cubes. When the blade is shock cooled in the oil, the cubes shrink and close up too quickly for the carbon to float out, trapping the atoms inside the cubes. This makes the steel very rigid and hard, very hard to dull, but very brittle as well. To toughen the steel, I needed to heat the blade to around 400 degrees, which I did with the kitchen oven. This opens the cubes up a tiny bit, allowing a few carbon atoms to escape, lessening the pressure and making the blade much tougher, while still retaining it’s ability to hold an edge, that is, not dull.

The freshly quenched blade. At this point, I could break the blade with a few fingers

The process of heating the blade in the oven to toughen it is called tempering. I left it in the oven for three or four hours, giving the blade time to fully get to even heat, inside and out. The temperature at which I temper is determined by the amount of carbon in the blade, most files and rasps, like this one, having about .90% carbon by weight. While the blade tempered, I began working on the sheath. I first cut out the leather in the the shape I wanted, which I would later fold in half, using a paper cutout model as a size reference.

The leather will later be folded in half

I then use a metal stamp to make a decoration along the edge, quite easy to do as leather takes stamping very nicely.

I will later true up the edges of the leather

I set aside the leather for now, as the next step in sheathmaking requires the nearly finished knife.

After the blade finished tempering, I cooled it and roughly sanded away some of the black scale on a 220 belt. I then assembled the knife and used a cobalt alloy drill bit to drill through the handle and tang.

I took out the blade and put it in the clamp, bevel up, and began hand sanding. This is the most tedious and boring and taxing part of all of bladesmithing. I start with 220 grit sandpaper and work upwards, to 600, using a piece of wood for even pressure.

This can sometimes take hours to sand a knife, I’m not sure exactly how long as I tend to not be able to sense time well when bladesmithing. The worst part is taking out the small scratches left by the grinding belt, as they can be very deep and I’m removing all the steel within an inch radius with sandpaper to grind down even to the depth of that scratch. Anything I don’t get with the very first grit of sandpaper I can’t get out later.

Every one of these scratches has to be sanded out, it can sometimes take up to fifteen minutes just to take out one scratch. It helps if they are all in one area

Finally, I finished sanding, at 600 grit.

600 grit blade

I began to get ready for the final assembly of the blade. The pin material I had was a little too thick, so I had to grind it down to size. To get it evenly ground without any facets, I put the rod in the drill and ran it against the belt grinder, the rotations of the drill grinding the rod evenly on all sides, bringing it to perfect size for the hole.

As 36 is a very rough grit, it creates tiny ridges all around the pin, which will give the epoxy later a very good grip

I then mixed up the epoxy (using the pin; it gets the pin nice and covered) and dabbed a generous amount into the handle cavity.

The tape roll at the bottom is just so I could hold up the handle, take a photo, and hold the pin all at the same time

I also slathered a little on top of the wood so there would be no space between bolster and wood, in case the drilling had been a millimeter off. I slid the bolster onto the tang and the tang into the handle, and after pressing together and making sure the blade was straight, inserted the pin.

Freshly epoxied knife