How to Cut String or Cordage Without a Blade

Introduction: How to Cut String or Cordage Without a Blade

About: What's up nerds? My name is Jeremy and I am currently in college majoring in mechanical engineering. Being active is the name of the game and I enjoy most outdoor sports and like to tinker and build on the s...

Along with a knife, cordage or string is one of the most useful things you can have on you in the wild. Whats stinks is when you have a string but no knife or scissors. What do you do? You could try and gnaw your way through the cord, but you could be dead before that happens especially with thick cord. So why not try these helpful tips? Because you don't like me? That could actually be a valid reason, but for everyone else lets get to it!! (I was going to put a third exclamation point, but that would have felt cheesy, don't you agree?)

Step 1: Materials

Here I have compiled a lengthy, in-depth materials list.
  1. Cord or string of varying thickness (not a full size rope please)
    • note: it must be synthetic cord for these methods to work
  2. Another piece of cord that is the same thickness or thicker
  3. Matches, a lighter or other controllable flame source (firebreathing?)

Step 2: The Fiery Friction Saw

In this corner we have a string and in that corner we have . . . a string. Should be a good fight folks. Now sit back, relax, and enjoy the show. Just kidding, unless someone else is doing this for you you are going to have to get up. Okay, now that we are all ready lets do this. If you have ever held a rope while someone yanked it through your hands you know that rope can really heat up. The cause of this is friction as most people already know, but it can be used to your advantage. If you have two pieces of string and one of them needs to be cut this is what you do. It's called a friction saw. Take the string you want to cut and tie two overhand knots in the middle of it. Make them about an inch apart. See the note below on this. Anchor the string that you want to cut loosely between two solid points (trees, fence-posts, chair legs, etc.). It should have a considerable amount of slack. Now take the other string and tie a fixed loop in both ends, I prefer a bowline for the loops. If you want a demo of a bowline just ask in the comments. Now take the string with the loops and pass it under and over the string you want to cut and grab both loops. Pull the cutting strings ends slightly apart and begin to saw back and forth with the string keeping it in-between the two overhand knots. Gradually increase speed until the string cuts from the friction. The string will snap in threads so don't expect the whole thing to go at once. If you look at the pictures you can see that the overhand knots prevented the string from unraveling. Congrats, you just made a friction saw!

**the string that I am using is three strand twisted. This is an older style where three smaller strands of string are all twisted together as opposed to a braided kernmantle rope (like paracord). The problem is that these strands can untwist when they are cut. By tying the two overhand knots and making the cuts between them you prevent the string from unraveling after the cut.**

Step 3: Notes on the Friction Saw

Some of you may be wondering, how did that work? If you aren't wondering then skip this step, or read it to make me feel like I am appreciated. Even though you are using the exact same type of string each one is experiencing different amounts of friction. The string you are cutting with is being sawed back and forth so the friction and resulting heat are dispersed along it's length. It still does heat up and if you look at the pictures you can see my cutting string is a little fuzzy. The other string has the friction concentrated on that one spot so the heat builds up and eventually cuts/melts through it. This method might work with natural fibers, but be careful because the friction could lead to the string catching flame.

Step 4: Melting With a Match

This is my preferred method for many reasons. It is faster, more efficient and leaves a finished end on the string. It might take a while with thicker cord or rope so I would advise to use this method on thinner strings or cords. As I mentioned before synthetic string can untwist which makes it a pain to cut with any method, but using a match is so efficient that I do it in place of using a knife or scissors. All you need to do is take the length of string you want to cut and drape it over two raised platforms like cups, chair backs etc. This is to keep the string and the flame off the ground. I used glass cups because they won't catch fire if I do something dumb. Now strike the match and hold it right under the spot you want to cut. Make sure not to actually touch the string with the match or they could melt together. Keep it there until the string melts, leaving two perfectly finished ends. See the pictures if you are confused. It is also a good idea to weigh the string down with something so it doesn't fall off the cups. This method should NEVER be used on natural string as it will catch fire instead of melting.

Step 5: Final Words

Now this Instructible is done, finished and complete. You may be happy that you don't have to endure it any longer or you may be sad that it is, at last over. As usual if you have questions, ideas or suggestions for a new Instructible, I would love to hear them in the comments section. Thanks you for reading and good night! Unless it's the daytime while you are reading this, but who knows?

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    2 Discussions


    5 years ago

    here is an idea... reverting to primitive time mind you.... and providing you are in a rocky environment. Tie string as you did, lay it over a sharp rock and either but tension and drag over rock or use another rock like a hammer. Have used your method before, just forgot to tie knots and ended with first mess.