I’d like to share the tips and techniques of making a sheep’s foot, or drop point knife for your kit. This project took a couple of months in my spare time, and served as a good winter project for the upcoming season. The tools required for this project range from the most rudimentary to power tools if you have them available to you, and require a moderate amount of skill to complete the project. I’ll use the materials and methods which were used in this project to keep it cohesive.
Minimum tools required:
1. Hacksaw
2. Grinding wheel
3. Drill
4. Sanding block
5. Wood rasp, combination flat and round sides
6. Files for metal, coarse and fine
7. Vice
8. Sandpaper from 120-1500 grit
9. Magnet
10. Hammer
11. Electric Heat Gun
Additional tools to make the project quicker & easier:
1. Belt sander
2. Polishing Wheel for metal with polishing compound
3. Angle grinder with cutting wheel
4. Drill press
Materials needed:
1. Knife blank
2. Small piece of tiger striped, or curly maple for the grip
3. Brass rod for pinning the grip
4. Aqua fortis stain (buy or make your own)
5. Leather for the sheath
6. Needles, awl, and thread for the leather sheath
7. 2-part epoxy glue
8. Tung oil for finishing the grip
9. Safety equipment; impact and chemical resistant glasses, or face shield, leather gloves, welding gloves, and heavy duty rubber gloves.
10. Rags
11. Quart of vegetable oil for quenching
This is the original design inspiration, from George Newman’s and Frank Kravic’s book, the Collector’s Illustrated Encyclopedia of the American Revolution, page 172. Of course, you can choose any blade style you wish. Unable to locate the proper size bone, I switched the grip material to a piece of tiger striped maple I had laying around.
Using a piece of car leaf spring, at the size listed, and used a friend’s forge to rough out the shape, and thinning it as it was being worked. Once it’s close, let the blade and tang air cool to make the metal softer and easier to work. Leaf springs are a high quality steel which yield a hard and sharp edge. Once it was roughed out, I drew out the shape (marked in white) on the metal blank, using a hacksaw to cut the shape out, and finishing it up on the grinding wheel to clean up the edges. Be careful of the sharp edges and corners this can produce. Handle the blade with leather gloves to prevent cuts. The blade was then ground down to a 25 degree angle, the thinnest portion being the cutting edge. File and sand the blade and tang to get rid of any high or low spots that will cause you problems later on. A glossy, polished, finish isn’t required at this point.
Once the blade and tang are smoothed out the next step is to heat and quench the blade to harden it; do not heat the tang so it remains soft. For this part of the project, a rosebud tip was used on a oxy-acetylene torch to heat the blade. We used a magnet to determine when the metal is at it’s optimum temperature for quenching. When the blade is no longer magnetic, quench it directly in the vegetable oil, cutting edge first. Be careful, using your safety glasses and welding gloves, as the oil may catch fire. Allow to cool to the touch.
Clean up the blade with a wire brush, sand paper, or belt sander to remove the scale and black oxide which remains, bringing it to a moderate polish.
Next, the blade must be tempered. Pre-heat your oven to 500 degrees, and place it in the oven for an hour. Remove it from the oven and let it cool. Repeat this step two additional times. This allows the blade to be sharpened without being too brittle and breaking during use.
You can then bring it up to it’s final polish using a belt sander, sandpaper, polishing wheel, etc., then wrap it in a few layers of masking tape to protect it in the next steps.
ATTACHING AND PINNING THE HANDLE
The next step is to take your wood and attach it to the tang of the blade.
I find it easiest to use 2 part epoxy to secure the wood to the tang, which also fills any uneven gaps.
Mix a generous amount of 2 part epoxy, and slather it on both sides of the tang, position the wood, and clamp it in a vise and leave it for a few days. Let it fully cure before removing it from the vice or clamps. Don’t worry about being too neat with the epoxy, any excess will be removed later, and disappears.
Once the epoxy is cured, it’s much easier to drill and locate the brass pins through the tang. It lines up easily using this method.
Next, get yourself some brass rod. I picked this up at a local hardware store for a few bucks; 3/16” diameter was used for this knife. Measure the width of the handle, and using a hacksaw, cut 2-3 pieces of brass rod longer than the width of the handle so about 1/8” of the brass rod protrudes from the handle on both sides. Clean up the burrs on the ends with a hand file or on a grinding wheel.
Using a drill, select a bit made for metal which is the same diameter as the brass rod. Secure the knife in a vise or clamp it down to a secure surface. Making sure to keep the drill 90 degrees to the steel blade, drill 2-3 holes (your preference) though of the wood and tang all in one pass. This is where a drill press comes in handy. Dry fit the holes with the brass rod to make sure that they pass all the way through.
Mix up a small amount of 2-part epoxy to coat the holes for the brass pins. Coat the inside of the pin holes. Push the brass pins through so that you’ve got a bit sticking out from each side, and leave it to cure overnight. The epoxy holds them in place nicely for the next step.
Once the epoxy has cured, you’re ready to set the pins and spread them into the handle. Place one of the pins on a steel surface, such as the flat area on the back of the vise, and carefully pound the pin with a hammer so that it starts to peen over, or takes on a slight mushroom like shape. This step expands the brass pins inside the handle to secure it permanently to the wood and steel. Be careful not to bend the pin while hammering it over, or spread the pin too much it as it will crack or split the wood on the handle. Turn the knife over and repeat on the opposite side. Repeat this for the remaining pins in the handle. File down the protruding brass pins to be even with the wood surface.
SHAPING AND FORMING THE HANDLE
Place the knife blade in the vise between 2 pieces of scrap wood to protect if from the vice jaws, and secure it in the vice at an angle which is comfortable for you to work. Using a wood rasp, begin shaping the handle to your liking. Be mindful of the brass pins while shaping as they will dull your wood rasp; switch to a metal file to keep them level with the wood surface. Once you’re satisfied with the shape and feel of the handle, sand it down with sandpaper using a coarse to fine method. This one was finished with 100 thru 1500 grit sandpaper.
FINISHING THE HANDLE
This was the most intriguing portion of the project as I’d never tried this finish method previously. Being a highly figured tiger striped maple wood, Aqua Fortis was used to accentuate the grain to give it more contrast. While Aqua Fortis is commercially available in small amounts, I opted to make my own after researching how to bring out specific colors with different formulas as I wanted to bring out the red hues in the wood. Here’s formula used for this piece:
• 400 ml distilled water
• 100 ml lab grade nitric acid
• 1.5 oz very old barbed wire cut into pieces
• 1.5 cast oz iron broken off from a rusted old boat trailer axle.
MIXING THE AQUA FORTIS
BE SURE TO OBSERVE ALL SAFETY PRECAUTIONS WHILE MIXING AND USING THIS!!!
Nitric Acid is highly corrosive and will burn skin and eyes.
Mix this solution outdoors, as it emits fumes while reacting. Do not breath the fumes.
Always wear a face sheild and suitable rubber gloves when mixing and handling.
If spilled on skin, neutralize the acid with either household ammonia, or moistened baking powder immediately, and flush with lots of clear water.
Nitric acid is also an oxidizer, so dispose of any rags and any combustible material that may have come in contact with the acid solution safely. Spray any spills with ammonia to netralize the acid.
Always add the acid to water, never water to acid as it may cause a violent reaction if not done in this order.
In the photo above, I placed a heat-resistant Pyrex graduated flask inside a plastic bucket as added protection and containment when mixing the solution. Fill the flask to 400 ml mark with distilled water, then slowly add 100 ml nitric acid.
AGAIN, NEVER ADD WATER TO ACID TO PREVENT A VIOLENT REACTION! Carefully add the metal to the solution as not to let it splash. In a few minutes, the solution will begin to move around and bubble up, giving off fumes. DO NOT INHALE THE FUMES!
The solution will also give off heat as well, so put it somewhere it will be safe if the reaction gets really hot. Do not cover the flask as the pressure from the reaction will blow the cover off. This will continue to react for several days. When the solution quits moving, bubbling, and emitting fumes, it’s ready to use. The color of the solution will go from clear to a dark brown with a greenish tint to it. See the photo (right) for the visual. Keep from freezing and the outdoor elements.
STAINING THE WOOD WITH THE AQUA FORTIS
To use the finished stain, apply a coat of the aqua fortis to the wood, being careful not to get any on the blade or tang, and let it dry. This is usually pretty quick as it soaks into the wood; it takes about 10 minutes. Once it’s dry, take the heat gun and apply heat to the wood with a constant motion to get an even color. Do not concentrate the heat for any amount of time in any particular area as it will appear as a dark spot, or possibly burn. Notice how the darker grain is getting accentuated.
When the wood has enough contrast, spray down the entire knife with household ammonia to stop the reaction
and rinse with clear water, wipe down, and let the wood dry overnight. See the below photo.
You'll get similar results depending on the wood and grain structure you have.
APPLYING THE TUNG OIL FINISH
When the wood is dry, it’s time to see the results of all your work. Apply the tung oil with a soft rag, let it soak in for 15 minutes, then wipe off the excess with a clean rag, and let it harden/dry for 24 hours. Polish when dry.
At this point, the wood has taken on a darker, deeper red color. Once the tung oil sets up, the finish will dull somewhat, but the finished gloss depends on how many coats of tung oil you apply to the wood.
Polish it with a soft rag between each coat. I’d recommend at least 3 coats to protect the wood from water; add more coats if you’d like. Finish the entire knife with a hard paste wax to keep it from rusting.
Complete your project by making a sheath of your liking. Check out this link for making a sheath: https://ofsortsforprovincials.blogspot.com/2011/03/18th-century-knife-sheath.html
Finally, it’s time to put an edge on your blade, and start using it. The next time you see a craftsman selling his wares, you’ll now understand why hand made goods are expensive; chances are that if they charged the minimum wage per hour which they put into it, you wouldn’t be able to afford it. Enjoy!