Introduction: How to Make a Tanto-Style Knife
About 3 months ago, I made a samurai sword using scrap metal. I recently found out that there is another kind of knife that has a similar shape to the sword called a tanto, and I thought it would be fun to make. I also decided to make this knife specifically because it looked slightly easier to forge than other knives.
Also, if you haven't tried forging before, I recommend watching forged in fire, as it was the tv show that inspired me to start forging. If you arent trying it because you don't have a forge, you also still can do it. The absolute least you need is an angle grinder with grinding, cutting, and polishing disks, a charcoal forge for heat treating, and a handheld drill or drill press.
I hope You enjoy Reading!
1.5" Width X 9.5" length X 0.25" thickness Hardenable steel
3/16" Brass, Copper, Or Steel Rod
3/10" to 1/2" Wooden Handle Scales (or another material, if you have it.)
100 - 320 grit sandpaper (Or Higher if you want a better polish.)
Cutting and grinding disks
3/16" metal drill bit (or the size of the brass rod you have)
Coal/propane forge (optional, can also use butane or oxyacetylene torch)
Angle Grinder belt grinder or belt sander
Drill press or handheld drill
Anvil (optional, only used if you want to forge rather than grind to shape.)
Beveling Jig (optional, good for making even bevels if you are a beginner.)
Step 1: Using Hardenable Steel for Your Knife
If you want to make a knife that is strong and lasts as long as you need it, you will need to find the right kind of steel to make it out of. There are a few different kinds of steel, but you will want high carbon steel over other kinds if you want the knife to last. High carbon steel can be found in springs, crowbars, files, hammers, and other tools. If you want to test if your steel is hardenable, the easiest method is called spark-testing. Spark testing is where you grind on the steel you are thinking of using for your knife until it produces sparks. If the steel has a bushy spark pattern (much forking) that starts at the grinding wheel, then the steel is most likely hardenable and is good for knife making.
(Be aware that spark testing isn't always 100% accurate and your steel may be mild even if it produces sparks like hardenable steel.)
Step 2: Designing (Optional)
although not be very important to you, to me it is one of the most important steps in the knife-making process. I think the reason it is important to design your knife before you start making it is that it is the very first way to know what the final product will look like. If you don’t agree with me and think you don't need to design your knife, then go ahead and skip this step.
Step 3: Forging/grinding to Shape
Always use eye and ear protection while grinding and forging. I also recommend using welding gloves while forging so you don't get burned.
Usually, when I make knives I grind them to shape rather than forging, but I am not as good at forging as I am at grinding, so I want to improve on my forging skill so I can forge knives out of steel that isn't the right thickness in the future. (Like leaf springs) In order to forge out the handle, I used the horn of the anvil because it made a nice and even dips in the steel for the handle. also, since the tip of the knife is angled, I used the angle grinder and just cut the tip shape while cutting the piece of steel. Tanto knives also have a slight curve in them, a bit like samurai swords, so I forged that in as well.
This step will take the longest out of any other step, so be patient. The better you do on this step, the better and easier the other steps will be.
Step 4: Quenching
This is one of the most important parts of the knife-making process. the reason this step is important because it is where you put the strength into your blade. The way you quench is by heating up your blade to between 1050 and 1090 degrees Celsius (1922 and 1994 degrees Fahrenheit). More often than not, you won't be able to measure the temperature accurately, so just heat it up until it is a red to orange color. You can heat it up using a propane or charcoal forge for a full blade quench, but if you don't have one of these two things you can use an oxyacetylene or large butane torch for an edge quench (Advantages of an edge quench over a full-blade quench include making the blade less brittle, and the blade having a reduced risk of bending or cracking, but edge quenches are much harder to get right if you are a beginner, so I recommend just going with a full blade quench the first time)
you should always keep in mind the material of your quench tank. You should not make your quench tank out of anything flammable like wood in case the oil catches on fire. Also, don't use anything that could give off toxic and harmful fumes if exposed to heat, such as PVC. A good kind of quench tank to use is an ammo can, because it has a lid that can be easily closed if the oil catches fire, and it won't give off toxic fumes if exposed to heat. (I recommend you use corn oil to quench because it is a non-toxic and cheap buy.)
Step 5: Handle Making
Picking a Handle Material
Picking the right handle material while making a knife handle is very important because some materials are stronger and better for knife handles. There are a lot of different types of handle materials to choose from. I usually use walnut because it has a good balance between strength and looks. One of the best materials you can use though is micarta because it is very strong and looks nice. A downside of micarta is the fact that it is expensive. The reason I don't use micarta in my knives is that I don't have any and like I said, it's expensive. A few other materials you can use for your handle are bone, g-10, aluminum, or stainless steel. Also, remember to wear a dust mask while working with any of these materials because they can be toxic and harmful to your lungs.
Assemble The Handle
for this step, you will need your handle material, a 3/16 inch brass rod, and your 5-minute epoxy. First, you mark out the shape of the handle on your handle scales and mark the holes on the tang. After cutting the handle scales out, (using a band saw or a jigsaw) drill holes out on the markings that match the holes on the tang. (Be sure to use a drill bit the size of the brass rod you are using.) Then, cut two pieces of brass rod to around 25 mm each. After that, put the two pieces of the brass rod through the handle scales and tang, and glue it together with 5-minute epoxy. (Remember to clamp it while the epoxy is drying because it will hold together much better and be stronger.) After the epoxy dries enough to hold the handle together (5-15 minutes), use a belt sander to sand out the shape and an orbital sander to round off all of the uncomfortable edges until it feels good to hold.
Step 6: Finish Work
Knife sharpening is a very tricky thing to get right when you are a beginner but is also a very important step in the knife-making process. I normally choose to use a belt sander or angle grinder to taper the edge down until I am satisfied with the sharpness. Although using a belt sander is the easier way to do it in my opinion, you can also use a tool called a sharpening stone. This takes longer to learn to use but can produce a much sharper edge. I don't know much more about sharpening stones, so I recommend looking up how to use one on Youtube because there a lot of people there that know much more than I do. (I recommend using a belt sander at first if you are a beginner.)
You can polish your blade in one of two ways. You can hand sand or use a belt sander. The advantage of hand sanding is the fact that you can get a much better polish with it, but it will take quite a while. Using a belt sander is the opposite: it takes less time but doesn't make as good of a polish.
There are a few different ways to finish your handle, but since I don't feel like explaining them all, I will just focus on the one that I did, which is called charring. This is where you use a flame from a blowtorch or lighter to essentially burn the handle until it looks good. Be very careful while doing it though, because the heat from it can burn up the epoxy and cause gaps in the handle.
After you finish this step, you are done!
Thank you for reading, and I hope you enjoyed this instructable!