“Ops are pushed 1 hour, remain on station.” My PRC-152 spit this information out matter-of-factly as wind and freezing rain pelted me and my crew of Tactical Air Control Party (TACP) members on the top of a mountain. These TACP’s were going through a Combat Survival and Evasion course and I was their instructor. They were quickly slipping into stage 1 hypothermia on this freezing day in late February. We were delayed one hour on this mountain and I was sure that if I didn’t get a fire going immediately I would be dealing with some cold injuries. It had been a miserable trip thus far; I’d cut down more trees than I ever had in a trip in the last two days to build fires to dry out my crew’s clothing. If I hadn’t had the skills to sharpen my cutting tools it would have been even worse, as my axe and knives were so dull at the end of each day that they couldn’t cut vegetables smoothly due to the amount of use they got.

There are multiple ways to sharpen your cutting tools. Each have their own merits. Of any job in the military I’d argue that Survival, Evasion, Resistance, and Escape instructors likely use their cutting tools in the most extreme manner on a day-to-day basis. Going through training we are constantly assessed on our ability to sharpen our tools to ensure that they have a razors edge at all times. The method we use to sharpen our cutting tools in the field is not the best, nor is it the worst. It has it’s good points and it’s bad. The primary sharpening tool used is the Lansky Puck or variations thereof. The sharpening puck is a simple puck shaped stone with a coarse and a fine side. You start with the coarse side and then move to the fine side to finish the blade off.

SERE Survival | Basics of sharpening your cutting tools in the field
Tools of the trade: As a SERE Specialist Candidate we sharpened our Air Force survival knives using a file with no handle. It made sharpening our tools an interesting task to say the least.

The sharpening puck was chosen because of its versatility. It can be used to sharpen both knives and axes equally well. There are other tools that many SERE Specialist use in my career field to specifically sharpen knives (diamond sharpening stones) however they lack the versatility of the sharpening puck. When using the puck to sharpen a knife you start with it in your hand using the “barstool technique” whereby your fingers are all below the edge of the puck to ensure that you do not slice your finger tips off while sharpening your knife. Whet stones / sharpening stones work as they are extremely porous and will collect metal as you grind the blade against them. As these pores become clogged the effectiveness of the whetstone is reduced. To counteract this you can use a sharpening stone oil to lift the metal to the surface. In the survival world we rarely do this and instead rely on water and scrubbing to remove the metal from the pores. The rule of thumb is that if you use oil – stick with it, if you use water – stick with it. No switching back and forth.

To sharpen your knife you need to understand the bevel of the blade. A bevel is a sloping surface. Imagine if you will a triangle. At the tip of the triangle two slopes intersect at an angle relative to each other. Think of that triangle as the two sides of your blade meeting. To sharpen effectively we are aiming to have those intersect evenly (there are cases where you don’t. Again, sticking with the basics for now). There are a couple typical blade angles that we see. Axes typically are around the 30-40 degree mark depending on the type of wood being chopped. Working knives range anywhere from the 20-30 degree range. In the case of the handy US knife used in the SERE school we typically use 22.5 dergrees to make our life simple when teaching basic sharpening techniques.