It's Not Just For Parachutes Anymore!
I first encountered "paracord," more properly known as 550 line, in 1980, when I decided to take up skydiving.
Ooh, baby, where have you been all my life? Waitaminnit, different story. I met my future husband while skydiving, too.
In those days, student skydivers were outfitted with the same parachute type used in the D-Day invasion, because they were plentiful, cheap (army surplus), and easy to fly (as long as you didn't mind landing very hard and 2 miles from the drop zone...). The chutes were nylon, with nylon lines made of a braided nylon sheath enclosing seven smaller strands of twisted nylon, and a breaking strength of 550 pounds, thus, "550 line" for short.
The paracord bracelet, belt, and knife handle wrapping have been done to death, so lets look at some of the other uses for this stuff that is at least as versatile as duct tape.
I am going to refer to this cord as 550 line, or just 550.
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Step 1: Know Your 550 Line: It's Strengths and Weaknesses
Nylon is wonderful stuff; It's strong, weather-resistant, abrasion-resistant, rot-resistant, and relatively inexpensive. 550 line is very durable, and very flexible, thanks to it's composite construction. There are a few things to be aware of, however.
- The UltraViolet in sunlight will cause it to lose strength, although it could take years. Many of our uses need only a fraction of it's strength, though, so it is suitable for many outdoor tasks (but don't leave your parachute out in the sun).
- Nylon stretches, quite a lot (20% or more), before it breaks.This can be a good thing or a bad thing. If you like having some warning that you're over-stressing your cord, it's a good thing. If you need it to absorb some shock load (As it does in parachutes), it's a good thing. If you tie something up drum-tight, though, you'll probably have to tighten it up again in a few days. If you put a large load on nylon line and stretch it, then wind it on a spool, it will crush the spool when it relaxes again!
- Remember that 550 pounds is the breaking strength. Your working load should never be more than 50% of that, I.E. 275 pounds. Parachutes had 36 of these lines to support one soldier.
- You might notice that some of the "Cheapo Paracord" nylon line out there might look like 550 line, but doesn't come close to living up the spec of real 550. If you'll be using it in a critical application, make sure it is real 550 line. If there is no spec for breaking strength, assume it's an inferior copy.
Step 2: Things Never to Do With 550 Line
- Don't even think about using 550 as a climbing rope. Remember how I said, "Maximum load is 50% of breaking strength?" You're probably saying, "No problem, I weigh less than 275 pounds." That 275 pound figure is static load. That's the load you'd be putting on the line if you were just hanging there. But, you're never just hanging there. You're jerking the line around, and this puts on a dynamic load up to several times your weight. Remember the parachutes? When that parachute is opening, the instantaneous load on that line could easily be ten times the actual suspended weight. Besides, 550 line is too thin to get a good grip on anyway. The only exception is if your life is in imminent danger and the 550 line is your only way out.
- For the above reasons, 550 also does not work as a tow rope. Even if you think you can braid several strands of it together, it will still probably break on you. You simply can't braid it well enough to have all the strands under equal load. One will break, then the next, and the next.
- Don't let 550 slide through your hands at high speed unless you're wearing heavy gloves, and maybe not even then. The stuff seems pretty slippery until it gets going fast. The rope burns will be memorable.
- Never let it cross over itself and rub. Nylon has a low melting point, and if two strands cross each other and rub together, chances are the one moving slowest will melt and break from the friction.
- Don't trust knots in 550 unless you really know your knots. Nylon is slippery, and will untie itself under tension if you use the wrong kind of knot.
Step 3: Melt It to Stop Fraying
Nylon's low melting point can be used to your advantage. Sailors went to all kinds of trouble to keep the ends of their natural fiber ropes from fraying; All you have to do is apply some heat to the end of your 550 line. The flame from a match or lighter will melt the fibers together so they won't fray. The amount of melting you do will depend on how nice you want the end to look. Usually just a little melting is enough. If you continue to apply flame, the end will melt into an ugly blob, and then catch fire and drip melting nylon on you. This Really Hurts! Molten nylon sticks well to skin, making a nasty burn. if it does catch fire, blow it out quickly.
Those big ugly blobs are also brittle, hard, and sharp. Not ideal.
If you need a smooth end that will fit in an eyelet, say, there are tricks you can use. One is to melt the end into a blob, then whip the end around quickly while still molten. This will stretch the melted end into a point that will work well in eyelets. Be careful not to do this if anyone else is in your line of fire; you might throw a drop of molten nylon at them.
If you're braver, quick with your fingers, and not afraid of a little pain, you can also lick your fingers and quickly smooth the melted end out as it cools. I am not responsible if you burn yourself!
If you have a soldering gun or hot knife tool, you can cut the nylon with it and fuse the end in one operation. Be advised that if you do this with a soldering tool, it may never be any good for soldering again. I keep a dedicated soldering gun tip just for use as a hot knife.
Step 4: Gut It
There are really two kinds of 550 line: the way it comes off the spool, and the sheath that's left over after you remove the 7 inner strands (The "guts").
Why on earth would you remove almost half the strength of your cord by taking out the center??? (7 X 35 lbs = 245 lbs.; 550 lbs - 245= 305 pounds for just the braid.)
Simple. If you don't need the full strength, the gutted cord is flat instead of round, much more flexible, and easier to tie. Plus, it's hollow, and braided, which means not only can you slip it over something else, it will expand in diameter if you push on the ends, just like Chinese finger cuffs.
You can also "Finger-Trap" loops in it. I'll show you that later.
Don't fuse the ends if you're going to gut your cord. Fuse them after gutting.
Gutting 550 is easy, though it gets harder the longer the piece you're working with. The way to do it is grasp the inner strands and push the sheath off of the strands. The sheath will expand and slide off easily. You will have to "massage" the sheath off with a longer piece; Just hold the inner strands with one hand and stroke the sheath from that end toward the other end.
Step 5: Tie It
Some knots tied in nylon will slip; Here are a couple of reliable ones.
When joining two similar cords, Put the two ends together and tie them both together in a square knot.
When tying a 550 line around something, the Surgeon's knot is slip-resistant. This is tied like a square knot, but the running end goes through the loop twice instead of once.
I am not (Knot?) a knot expert, but these two knots will handle 90 percent of all situations.
Step 6: Untie It
A good knot gets tighter as it has tension applied to it, which is good, but sooner or later you'll have to untie something.
The sailors have us covered there, too. They have probably forgotten more about rope than us landlubbers will ever know, or need to know.
Sailors use something called a "Marlin Spike" to undo knots. This is nothing more than a spike with a smooth, but not sharp, point on it. A nail will do in a pinch, but if the object is to untie without damaging the line, the burrs on the nail point can cause damage to the fibers.
Simply work the tip of the nail, awl, or spike into one loop of the knot and start wiggling it in deeper, being careful to go into the knot but not actually into the line itself. It may take a few minutes, but eventually the knot will be loose enough to finish untying by hand.
Step 7: Protect a Wire
Since the outer braid of 550 line expands (somewhat) when you push on it, you can slip a gutted piece over a slim wire (Such as a speaker or headphone wire) as a decorative or protective skin. This will not protect a wire from heat (Use fiberglass tubing for that), but it's great for abrasion protection.
It's also an easy way to add a "steampunk" look to a wire. Use muted colors such as black, brown or tan.
Step 8: Slip It Over a Zip Tie
You can also slip a gutted piece of 550 over a zip tie to add some cushioning and anti-chafing for anything subject to rough duty, or for decoration.
Step 9: Sew It
The best, strongest way to attach line to fabric is not grommets, but sewing. Gutted 550 is somewhat easier to sew with a straight or zigzag stitch, un-gutted sews best with a zigzag. This is how lines are attached to parachutes; The lines are not only sewed on, they go completely over the top instead of just being sewed to the hem. The secret to a strong line-fabric joint is spreading out the load as much as possible.
Step 10: An Adjustable Necklace
Want an easy, durable necklace without a fastener, but not as long as most continuous necklaces? Gotcha covered. In only a few minutes, you can make a necklace long enough to slip over your head, and still short enough to be a choker if that's your style.
Start with a piece of gutted 550 about 24" long. Thread whatever charms and danglers you want on, then take one end and tie it in a tight square knot around the other end, leaving about a one inch tail. The cord the knot is tied around should be able to slide through the knot with a little effort. Repeat this with the other end. Sew the two tails down to their respective ends.
Now, if you pull the knots apart, the necklace gets shorter, and if you pull the cord, the knots get closer together and the necklace gets longer. Put it on over your head, then adjust the length to whatever you want!
Step 11: Shoelaces That Will Outlast Your Shoes
In this step, I'm going to introduce another way to finish the ends of 550 line.
Making shoelaces out of gutted 550 is practically a no-brainer, but you can make a smoother end on the line if you use heat-shrinkable tubing.
Cutting the ends of the line at a slight angle will do two things: It will make it easier to slip the shrink tubing over the ends, and the resulting tip will have a bit of a taper, making lacing your shoes a pleasure.
Cut a piece of shrink tubing about 1/2" long and work it over the end of the line so there is just a tiny bit of line sticking out of the end of the tubing. Shrink the tubing with a flame or heat gun. If you've got some decent calluses on your fingertips, you can roll the tubing while it's still hot into a nice shape.
One note worth considering: As I said before, nylon likes to untie itself, and bow knots are quite susceptible to this phenomenon. I always tie a square knot over the bow knot, and they never untie.
Step 12: 30-Second Zipper Pull
Okay, this might actually take you a couple of minutes to make, depending on your skill level. The main reason I include this is to introduce the Larkshead knot.
Cut a piece of 550 line, gutted or not (Gutted will probably work better), around 6-8" long, finish the ends however you want, fold in half, thread the resulting loop through the zipper tab, put the ends through the loop, pull tight, you're done!
The larkshead knot is quick and secure for all sorts of applications where you can get the ends of the line through a loop. It may slip some, but cannot come completely untied as long as the line ends are secure.
Step 13: Replace Your Flagpole Lanyard (Before It Breaks!)
If you own a flagpole, you are in one of two groups: People that have had the lanyard break and had to take down the flagpole to fix it (or stand on a tall ladder), and people that will have this happen sometime.
Most household flagpoles I've seen come with cheesy cotton cord for the lanyard. I live in Arizona, where ice and snow isn't much of a problem, but the Sun destroys everything sooner or later. The cotton cord only lasted a year or two, and then I was taking the flagpole down again.
I replaced my lanyard proactively with 550 line (un-gutted) almost 2 years ago and it still looks like new. Here's how to do it before you have to do it the hard way.
Untie the lanyard where it's tied together. Lay your new cord beside the old cord with about a 6-8" overlap, then wrap the entire overlap tightly with electrical tape. Pull the other end of the old lanyard to gently raise the new one up and over the pulley. When you get your taped joint down again, un-tape it, tie the ends of your new lanyard together, run the flag up, and see if anybody salutes!
This is one place where sun damage to the nylon doesn't seem like much of a problem.
Keep an eye on it, and if it starts looking ratty, replace it again. 550 line is cheap, and climbing flagpoles is a real pain.
Step 14: Make a Snag-Free Loop
How about a loop of line that is smooth and sleek? Remember about the Chinese finger cuffs? I'm going to show you how to make a snagless loop in gutted 550 line.
You're going to need the awl or nail you used to work knots loose again. This time, start worrying away at a spot in the side of the braid. The object here is to separate some of the fibers without damaging them so you have a hole in one side of the braid.
Get a piece of fairly stiff wire, about 6-8" long, that will still bend. 22-gauge solid copper works well. Fold this piece in half and crimp the fold a bit to make it narrower. You've just made a crude needle. (They do make tools specially for doing this- they are called fingertrapping fids. Or, you can make one.)
Insert the "eye" end of the needle into the end of the piece of cord and out the hole you made. Take the other end and put it through the eye, not too far, just enough where it'll stay put. Now pull the needle back out of the hole, taking the end of the cord with it. This will probably take some massaging since we're using such crude tools, but it's doable.
Get the "inside" and "outside" ends even with each other, massage the hole closed again, and you have a very professional looking loop for buttonholes or other decorative uses.
You will still need to either tie a knot or put a stitch in the ends of the loop to keep it from undoing itself.
Step 15: Use the Guts
By now, you probably have lots of "guts" laying around. What are they good for? They are still pretty strong. Here are a few ideas.
- Heavy-duty sewing thread for leather crafts, etc. You might need to wax it.
- Embroidery floss.
- General purpose twine.
- And, of course, if it's a survival situation, plenty of uses.
I hope I've given you some ideas besides the tired old survival kit and bracelet stuff! Go out and Tie Something.
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