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Knife Making: Transforming an Old Wrench into a Survival Knife

In this article, “Knife Making: Transforming an Old Wrench into a Survival Knife,” you’ll learn how to tap into your inner blacksmith and turn an old wrench into a functional and reliable survival knife. This ancient art of knife making is a valuable skill to have in your arsenal of primitive survival skills. Discover the step-by-step process and the necessary supplies required to create your own custom knife from a simple wrench. Not only will you learn the techniques involved in forging and shaping the blade, but you’ll also gain insights into heat treating and sharpening the knife to perfection. With modern tools and resources at your disposal, this DIY project will not only challenge your craftsmanship but also provide you with a practical and uniquely crafted tool for your outdoor adventures.

Knife Making Skills | Transforming an Old Wrench into a Weapon

Have you ever wanted to try your hand at knife making? This ancient art may seem lost in our modern world, but with a little resourcefulness, you can transform an old wrench into a functional and impressive weapon. In this article, we will guide you through the step-by-step process of turning an old wrench into a knife. So put on your apron and let’s get started!

Knife Forging Supplies

Before we dive into the process, let’s go over the supplies you’ll need for this project. Here’s a list of what you’ll need:

  • An old wrench
  • A grinder
  • Blacksmithing forge
  • A hammer
  • Knife sharpening tools of your choice

It’s important to note that safety should be a priority when undertaking any DIY project. Make sure to wear goggles, gloves, and, if needed, breathing protection to keep yourself safe from sparks and debris.

Step-by-Step Guidance for Knife Making

Now that you have all your supplies ready, let’s break down the process step by step.

Step 1: Choosing the Knife Side of the Wrench

Start by choosing which end of the wrench you want to use for the knife blade and handle. Use a portable grinder to straighten out the chosen end to ensure it’s suitable for the blade. Then, use the grinder to cut through the steel and shape the blade.

Step 2: Setting Up the Blacksmithing Forge

While you’re preparing the wrench, set up a basic blacksmithing forge. You can use an old grill or any solid platform where you can place burning coal. Make sure to incorporate a blowing mechanism into your forge to generate enough heat for forging the steel.

Step 3: Putting the Wrench on the Hot Forge

Once you’ve shaped the blade, it’s time to put it on the hot forge. Place the wrench on the burning coals and let it stay there until it reaches the appropriate temperature for shaping steel. You can determine the right temperature when the color of the steel turns red hot or yellow.

Step 4: Pounding the Steel

When the steel is hot enough, place it on an anvil or any suitable metal surface and start pounding it with a hammer. This step allows you to manipulate the steel and shape it into the desired blade form. Be prepared for some unexpected movements of the metal when hammered, as this is all part of the blacksmithing process.

Step 5: Making the Blade

Once you’ve achieved the desired shape of the blade, you can start refining it. Use a belt grinder or belt sander specifically designed for metal to smooth out the surface and add a sleek finish to the blade. This step will also give the blade an even and shiny stainless appearance.

Step 6: Heat Treating the Steel

After working on the sharp edge of the blade, it’s time to heat treat the steel. Place the blade back on the hot forge and wait for it to turn into a glowing red color. Then, remove it from the forge and immediately submerge it in engine oil to quench it. This process helps to harden the steel and ensure its durability. Allow the blade to cool for approximately an hour without applying any pressure.

Step 7: Sharpening the Blade

Once the blade has cooled down, it’s time to give it a nice sharp edge. Use a reliable knife sharpening tool of your choice to sharpen the blade and make it ready for use. Well-sharpened knives not only enhance their cutting ability but also ensure your safety during use.

Step 8: Appreciating Your Work

Last but not least, take a moment to appreciate your hard work and craftsmanship! Making a custom knife is no small feat and should be celebrated. You are now one of the few people who can call themselves a knife maker. Feel free to explore and diversify your skills by making other types of knives such as pocket knives, hunting knives, or even chef’s knives.


Knife making is an exhilarating and fulfilling endeavor that allows you to unleash your creativity and craftsmanship. The process of transforming an old wrench into a functional and impressive knife is a great way to showcase your resourcefulness and passion for the craft. With the right tools, safety measures, and step-by-step guidance, you can create a unique and durable weapon that will serve you well in many situations.

So go ahead, embrace your inner blacksmith, and start making your own custom knives. Remember to stay safe, enjoy the process, and continue improving your skills in the art of knife making.

Can I Use the Car-Drying Method to Preserve My Knife After Transformation?

I often receive questions like, Can I use the car-drying method to preserve my knife after transformation? It’s an interesting concept. However, while drying foods in a car might work for certain purposes, preserving a knife requires a different approach. Proper cleaning, drying, and storage techniques are key to maintaining the longevity of your knife after transformation. So, leave the car-drying for the snacks and focus on the right care for your knife.

Additional Resources

Are you ready to take on the challenge of turning an old wrench into a blade? Share your experiences and thoughts in the comments section below!

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Editor’s Note: This article was originally published in January 2019 and has been updated for quality and relevancy.