Introduction: Design and Build a Full Tang Knife
Building your own tools can be a great thing and knives are no exception. From the caveman times to Bear Grylls, knives have been an essential part of outdoor survival and just basic utility and around the house use. This Instructable is a basic guideline for making your own unique survival tool that will be suited to your use and designed to your specifications. Also, if you use recycled materials like I did, your knife should be practically free! This is obviously not the only way to make a knife. There are many other tried and true techniques, but this it what i have found to work best. If you don't find all parts helpful, pick and choose. develop your own basic style and make it work best for you. This could take one knife or it could take ten, but keep at it. A tool that you have made is truly a joy to behold. And just because I don't want to get in trouble is people hurt themselves: Knives are tools but also can be weapons. Treat them with extreme care and respect them. Making sharp pointy things has an inherent danger to it so use common sense. Also, dull knives are more dangerous than sharp ones. Forcing a dull knife will increase the chance of slipping and that's bad, even with a dull knife. Ok, I'm done ranting. On to the important part!
Step 1: Designing the Knife: Materials
The first step in making most things is a design and the same holds true to knives. To design my knives, I use graph paper, a metal ruler, a French curve, and a normal pencil. Also, since I use found metal for my knives, I like to have the metal in front of me so I know what I have to work with.
Step 2: Basic Design: Overall and the Handle
The essential parts of a knife are the blade and the handle, so this is where you should focus most of your efforts. If you want to spend time on guards and pommels and such, that's good too. I don't make them because I don't have access to soft metal (brass, copper, aluminum) and I don't have a band saw. For the design of this knife I had a freehand rendering that I drew in English class under my desk that I used as a template. I liked the basic proportions, but I needed to increase the scale by 75%. This made the knife too big for graph paper so i had to tape some together.
I started with the handle. Working off my original sketch and with lots of measuring, i drew a full scale rendering of the handle. To make curves I draw dots at the correct measurements, then connect the dots with a French curve. This is where a lot of personal preference comes in. Design what you like and what looks good, it's your knife!
Step 3: Basic Design: the Blade
When people see a knife, the first thing they see is the blade. Therefore, it should set the theme for the knife, and make the knife look great. For this knife I chose a simple blade with no complex curves. This basic type of blade is a good one to start with, because it is not nly easy to design, it involves less grinding, and functions well. This knife has an 8 by 1.75 inch blade so i started with a rectangle of these dimensions. I then drew a curve in that I thought went well with the overall knife design. The main image is the design cut out and ready to be taped to the stock.
Step 4: Making the Blade: Cutting From the Stock
Now the fun part: Rough cutting of the blade. this is where you go from paper to metal in the design process, and is the first step in the manufacturing of the blade. Start by taping the pattern to the blade; I use loops of masking tape. Then head outside. This makes a huge amount of sparks and sends small metal shavings all over. Clamp your workpiece to a bench of sorts (or an Adirondack chair). Put a cutting wheel in your angle grinder and have at it. But please use proper saftey gear!! I use a full face shield, ear protection and tight-fitting gloves, and if you work inside use a dust mask!
Start cutting away at the metal, staying away from the pattern. Make sure to leave yourself room to shape it on the grinder. make sure you don't overheat the metal, because this causes it to lose its temper. Sorry for so few pictures, its hard to cut and take pics at the same time.
Step 5: Making the Blade: Grinding the Shape
This step is fairly simple, the only tool you need is a bench grinder. You can use an angle grinder, but it can be hard to see what you're doing, and getting straight edges is hard to accomplish. I just recently got a bench grinder, and the work and pain it saves is amazing. Use the same safety gear for the angle grinder, and wear clothes you don't care about because they will get covered in metal. Again, sorry for the lack of pictures. It's kinda boring, but it is fun to see the knife take shape.
Step 6: Making the Blade: Grinding the Bevel
This step may be the one with the most consequence if you screw up. the cutting edge is the most important part, and when forming it, go slow. You only want to grind half of the edge away on each side. Make sure you clamp the blank securely. I like to use C clamps because they cover less of the knife. You don't want it moving anywhere while you grind.
To form the bevel I use a 36 grit wheel for my angle grinder, because it makes a wide cutting path. While forming, check the angle by looking down the blank. When you hit halfway, flip it over and grind the other side. when you see a wire edge forming, stop. you have made a successful edge.
Step 7: Making the Blade: Rust Removal and Finishing
Now for the part where your knife starts to look like a knife: Finishing. This makes it shiny, which as everyone knows is an essential part of a knife! This blade was made from an old backsaw blade, so it had some surface rust that needed to be cleaned off. To do this I used an angle grinder with a 120 grit flap wheel. Make sure to clamp it securly (Again, it's the Adirondack chair!)
Focus most of your effort on the blade, although you can clean the handle area too if you want. After you remove the rust and make it look halfway decent, it's time for hand sanding. Clamp the knife securely to a block of wood, then clamp that in a vise. I start with 180 grit and work my way up to 1000 grit. This gives it a nice smooth satin finish. On this knife I chose to go for a weathered-ish look. If you want you can use some rough sandpaper on the handle to help the epoxy stick better. Once you have a nice shiny blade it's on to the next step!
Step 8: Making the Handle: Rough Cutting and Gluing
The first step of making a handle is making the handle scales (Scales are the pieces that are on either side of the blade). For this knife I chose to use some nice red oak that I got at Lowes. Note: This was the only material that I actually had to buy. Yay for recycled materials! To make the scales, figure out the size by placing the knife over the wood and marking the largest dimensions you will need. Use a square to mark out a rough rectangle, then go ahead and cut it out. I use a table saw because it is fast and easy, but if you have a lot of patience, you could do it with a hand saw.
Once you cut out the scales it's time to glue them. This part is pretty easy, but you want to make sure and get it right. Mix up a good bit of glue (I use two-part epoxy), and spread it on a scale. place the knife on the scale, then repeat with the other scale. Get them lined up the way you like, then clamp them. I usually wait two hours before working with the knife, to allow plenty of time to set. Make sure to wear proper saftey gear like a dust mask! These fumes are nasty!
Step 9: Making the Handle: Achving the Correct Thickness
I have discovered that most knife handles shouldn't be much more than 3/4 inch thick, but since this is a big knife, I went a bit larger. Set your calipers to half the thickness you want, and start rasping. You could use a plane if you wanted to. Continue the filing until you get the correct thickness on both sides. This is faily quick if you have a sharp rasp, just make sure to file evenly on both sides.
Step 10: Making the Handle: Rough Shaping
Now for the most long and tedious part: rough shaping. Similar to grinding, this is where the handle looks more like a handle and less like a block of wood. This stage reqires a bit perception, since you want to know where the metal starts. Hitting metal with a wood rasp makes it duller. The basic idea behind this is use the rasp until you think you are close to metal, then switch to a file that can deal with both metal and wood. This part is fairly tedious, but you want to take your time. The pictures show the basic outline taking shape, which is what you want at this stage. Also, you may want to cover the blade with duct tape so you can clamp it in the vise and work on the whole handle.
Step 11: Making the Handle: Final Sanding and Installing Pins
Getting close to the end, it's just basic sanding and pins now. The sanding is pretty self-explanatory, just work through the grits until you get to about 320 or 400. If you want to be silly you can use up to 1000, but I don't think it would make a huge difference to the overall feel of the knife. This knife handle was sanded up to 320 grit before finishing.
Since installing the pins goes with final finishing, I'm going to include everything in one step. Since I don't have any fancy rivets and such I use a method that may seem like cheating to some hardcore knife makers: I drill through the handle and blade, epoxy the pins in, then file them flat. The first step in this process is marking the holes. I usually eyeball the marks, then check their orientation with a straightedge to make sure they all line up. Next, you want to measure and cut your pins. For this knife I just used a brass rod (it may be a welding rod). To measure, just lay them across the handle and mark with a Sharpie. Make them a bit oversized though. It's a lot easier to remove material than it is to add it. Clamp the rod in a vise and use an ordinary hacksaw to cut the pins off. Then it's off to the drill press! Clamp your piece securely somehow, then drill through everything in one go. I put the drill on its slowest speed and use a really sharp bit. Repeat with however many pins you want to. When you finish, make sure to double check the fit of the pins in the holes. If they just barely fit, then you're in luck! Just tap them in with a mallet and file off the ends. If they slide in easily, then its epoxy time! Mix up some more epoxy, then put a bit on the middle of the pin. slide it in, and wipe any excess epoxy with a clean rag. leave it to dry before filing. When It's dry, just file the pins flush using a mill file.
Almost there, don't give up now!
Step 12: Making the Handle: Finish Him!!!
It's the last step of construction! Technically this step is optional; if you want to leave your handle as bare wood you can. I chose to treat it with some Danish oil and two coats of polyurethane. The technique for applying oil is fairly simple. Just wipe off the handle with a clean cloth, then use a rag to apply the oil. make sure to get even coverage of the handle. I applied two coats, then let them sit overnight.
Before applying polyurethane, lightly sand the surface with the finest grit that you used. In my case, that was 320 grit. Then make sure you wipe off all of the sawdust, again with a clean cloth. Use a foam brush to apply a very thin coat of polyurethane to the wood. I used two coats, and sanded in between coats. After the last coat, let it sit for 24 hours. This gives it a chance to set completely. Congratulations, you're done with the manufacturing process!
Step 13: It's Sharpening Time!
This is where your knife finally becomes a tool! Getting a very sharp edge on a knife is essential, but can be a bit more difficult with a homemade knife. Grinding the edge by hand inevitably produces irregularities, but that is part of handcrafting your own tool. Small things like this can be worked around though, so don't worry. To sharpen my knives I work through a progression of stones; a coarse synthetic, medium Arkansas, and fine Arkansas. I'm assuming that anyone who gets to this last stage has a fairly good idea of knives and how to sharpen them, so I'm not going to include a whole slew of facts, techniques, and angles. If you want a basic primer, do a search for "knife sharpening" on Instructables. There are many good Instructables that cover this subject. Ok enough ranting about that, now back to the main subject. Work through your stones until you reach a nice sharp edge. At this point, you can leave it like that, or strop the edge. This produces a razor edge on your knives, and I like to finish my knives with it. I use a homemade strop to do this, and if there is interest in how to make and use it, please leave a comment saying so. To test the edge, try slicing up some paper. It should cut cleanly and easily, if not, keep at it. When you can consistently cut paper into ribbons with your knife, you're done!
Step 14: Congratulations! :)
At this point you should have a finished knife. There is great satisfaction in using a tool that you made yourself, and to see it perform as good or better than most store-bought knives. Also, being able to make a tool from scratch is a nice skill to have (for when the zombies come!). If there are any improvements or corrections that I need to make, please leave them in the comments and I will try to get to them ASAP. Also, if anyone makes a knife using this or any other Instructable for that matter, please post it. I think I speak for a lot of people when I say that I love to see what other people can do, and what twists of their own they add. Be safe and have fun with your new knife!
Thanks for reading and hope you enjoyed it!!