You've caught the knife-making bug, but don't want to wait until you can afford the right tools. While using a bench grinder to make a knife is doing it the hard way, it can be done. If you have an uncontrollable desire to turn an old file or snowblade into a knife, while the only power tool you possess is a bench grinder, you will have to use the stock removal method. Begin with a full-tang, wrapped-handle design.
Things You'll Need
- Pre-hardened steel bar stock
- Black permanent marker
- Bench grinder
- 24, 80, 120-grit grinding wheels
- Coffee can full of water
- Large, fully-charged ABC fire extinguisher
- Wrap-around eye protection
- 120, 180 and 220-grit belts
- Emery cloth
- Buffing wheel
- Buffing and polishing compounds
- Parchute cord or leather thongs
Acquire a pre-hardened piece of steel as close to the shape and dimensions of your chosen knife profile as possible. This may be an old file, saw blade, chainsaw bar or flat spring. Lay out your basic knife profile with a black permanent marker. Examples of knife profiles can be found in Resources.
Don wrap-around eye protection.
Use your bench grinder and coarse wheels, beginning with 24-grit or 80-grit to rough grind the knife profile and bevels. Use finer wheels next, as needed. Hold the steel in the correct grinding position, so that the blade blank cannot be grabbed by the wheel and flung down toward your body or up toward your face. This is just below the bulge of the wheel, with the wheel spinning toward you. Hold the blade blank at a fifteen-degree angle to the wheel when grinding the bevels, to achieve a 30-degree included angle.
Keep the blade cool by sprinkling it with water while you grind, any time your blade blank begins to change color. This prevents the knife from changing temper and becoming brittle.
Once your blade is a close to what you want your finished knife to be as possible, place it in your kitchen oven at 450 degrees Fa for one hour. Allow to cool slowly to room temperature. Different steels have different tempering ranges, but this will do until you can afford a forge or tempering oven. Repeat three times, grinding away any scale between heats.
Begin with 80-grit and work through 120, 180, and 220-grit belts to remove any burrs and finish-grind your knife. Hand sand with emery cloth. If you have buffing compound and a buffing wheel, remove the guard from one side of your bench grinder and replace the grinding wheel with a buffing wheel to polish your blade.
Wrap handle by criss-crossing parachute cord or leather things over it.
- Stock Decision Knives; Jon P. Moore
- Gypsy Wilburn; artisan and industrial blacksmith and blade maker
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