A knife forged from a piece of junk or scrap metal always comes with its own story and unique character. In this article, we’ll take a look at how to craft such an unforgettable blade by forging a knife from a brake rotor.
Are Brake Rotors Good for Forging Knives?
Depending on the metal content, most brake rotors can make an excellent material for forging a knife. Brake rotors are known for being strong and sturdy with a hardness level of around 58HRC. Making a knife from a brake rotor only requires a few basic blacksmithing tools that even a beginner can master.
However, if you’re still new to knife making, sharpening your brake rotor knife can be challenging. It will also require the use of a belt grinder and some advanced sharpening techniques.
Steps to Forge a Blade From a Brake Rotor
If you think you’re ready to turn an old brake rotor into an impressive knife blade, here’s how you can do it.
What you’ll need:
- Brake rotor
- Grinder
- Table vise
- Marker
- Belt grinder (optional)
- Safety Equipment
Step 1: Planning and Drawing
The first step is to plan your knife design and draw it out on the brake rotor with a marker. If you’re following a specific pattern, start by drawing the blade shape and then add other details such as the guard, handle, etc.
You can include the edge of the rotor as a part of the blade’s edge. You can also draw around the breather holes and include them in the overall design. This will give your knife a unique look and make it stand out.
This is also a good time to decide what kind of handle your knife will have. I’ve found wrapping some paracord looked really nice, but you can experiment with different materials if you like.
Step 2: Cutting Out the Shape
Secure the brake rotor on a table vise and use a grinder to cut out the shape you’ve drawn. Adjust the position of the rotor and move it around to remove as much material as possible.
Brake rotors are quite thick and relatively hard, so you may need to cut out small sections of the design one at a time. Make sure to take regular breaks and wear protective gear such as goggles and gloves during this process.
Step 3: Sharpening the Blade
Once you’ve cut out the shape of your knife, use the marker to trace the blade’s edge. If you have access to a belt grinder and are confident in using it, you can use it to sharpen the blade. Otherwise, you will need to manually file down and sharpen the edge, by hand!
For a smoother finish, use a round file or sandpaper to clean up the blade’s edge. Make sure to take special care when sharpening and filing down your brake rotor knife.
Step 4: Adding a Handle (Optional)
If you designed your knife to have a handle, now is the time to add it. You can use paracord or any other material that you like as your handle. Secure the handle using epoxy glue, rivets, or screws, and make sure everything is nice and tight before use.
Congratulations! You’ve just forged a knife from an old brake rotor. With some practice, you can make even more complicated blades and turn scrap metal into one-of-a-kind works of art.
Frequently Asked Questions
Now that you know how to forge a blade from a brake rotor, let’s go over some frequently asked questions.
Are brake rotors hard enough to make a good knife?
Yes, brake rotors are generally made up of a hard metal alloy that makes them an excellent material for forging knives. However, the hardness and strength may vary depending on the metals used in the alloy.
Do I need to heat treat a knife forged from a brake rotor?
No, heat treating is not necessary for brake rotors as they already come at a hardness level of around 58HRC. Heat treating may be required if you use different materials when forging the knife, such as mild steel or stainless steel.
What is the best way to sharpen a brake rotor knife?
The best way to sharpen a brake rotor knife is with a belt grinder. This will allow you to get an even and consistent edge on your blade. You can also use files or sandpaper for finer details and polishing, but be sure to take your time and work slowly.
Can I use a brake rotor to make a folding knife?
Yes, you can use a brake rotor to make a folding knife, but it will require some extra work and specialized tools.
You will need to drill holes in the handle and blade for the pivot and other folding components, as well as carve out grooves for the blade to lock into. It’s also a good idea to enlist the help of an experienced knife maker if you decide to take this route.
Final Thoughts
Brake rotors may not be the first material you think of when it comes to knife making, but they are an excellent choice for a durable and unique blade. Plus, you can have some fun customizing your design and adding details such as handles or breather holes.
Whether you’re just starting out or looking for a new challenge, forging a knife from a brake rotor is definitely worth trying.
Good luck and happy forging!