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Paracord, what is it, Suppliers and Projects.

What is Parachute cord or Paracord?

Paracord or more accurately Parachute Cord started life as a light rope originally used in the suspension lines of parachutes. After World War II the cords made their way to surplus stores where they were found to be very useful for many military and non military uses.

Originally, parachute cord was made of nylon. It is constructed of an outer braided layer and an inner core.

The outer layer is a braided sheath composed of many layers. This makes the rope smooth and easy to handle. The inner core is made from twisted 2 or more ply nylon yarn.

Para cord used in the military is strictly controlled by The US military MIL-C-5040H. It comes in 6 types: I, IA, II, IIA, III, and IV. The IA and IIA do not have cores, only the sheath, The type III, which is the best known paracord, is often called 550 cord. This is because it is rated with a minimum breaking strength of 550 pounds. Material is specified as nylon and stringent quality control and testing must be used if the rope is to be certified for U.S. Military use. 550 paracord is made of 7 to 9, 3 ply twisted inner cords and an outer sheath and 32 or 36 strands in the sheath. It measures about 4 mm in diameter.

Military grade paracord will also have one of the inner cords colour coded in order to identify the manufacturer.

Minimum breaking strength is an ideal strength measured in the lab. Once in use knots and fasteners reduce the usable strength. Some knots make a rope less than half as strong. For this reason a safety factor is used when the rope is used in critical conditions. Safety factors of 5 to 10 times are not unusual.

Not all paracord is US certified and many companies make good usable cord which do not comply with US certification. Many companies claim to sell mil 550 paracord but in fact do not. I'm not sure it matters much for most applications.

You can somewhat judge the quality of a rope by taking it apart and looking at the core. Are the core ropes tightly wound, even, smooth and not fuzzy? Similarly is the sheath even, well braided and smooth without pulled hairs, knots or uneven strands? One of the ways of telling polyester from nylon is by checking the stretch. Nylon is much stretchier and even more so when wet. Polyester is not so stretchy and wetting it makes no difference.

As expected higher standards of testing and quality control make a rope more expensive. This is not to say that some commercial rope is not well tested and as strong or good as true military grade rope. It you take a batch of rope, split it in 2 section and test one section while not do anything to the other section, the tested line will have to sell for more.

Suppliers

Paracord is a useful and fun rope to have around. It is available in many sizes and colours. Many companies supply it in varying quality.

Many rope companies sell paracord along with regular rigging ropes. Here are a few:Paracord.eu, The Paracord Store in Jenkintown, Pennsylvania USA, R & W Rope Paracord.com, Atwood Rope MFG., Extac Australia, Paracord.co.nz in New Zealand, Greenman Bushcraft, UK.

Survival Cord usually has some of the core ropes modified to includes fishing line, snare wire and fire starter tinder among the core ropes. The rope looks the same from the outside as regular paracord.

The following links are from Amazon.com. I tried to find reliable supplies with good ratings, and good variety.


Commercial paracord is sometimes made of polyester rather than nylon. Polyester is stronger than nylon particularly when wet. Nylon looses strength when wet while polyester rope strength is not affected.

Nylon rope is relatively elastic and can stretch when pulled. This gives it some give when used on a parachute, or as an anchor or mooring line.

Polyester is sometimes called Terylene, Dacron, or Trevira, these are trade names for the same material.

The safe loading of a rope is a 1/5 to 1/12 of its breaking strength. Remember that knots weaken a rope as does age, wear, chemical attack etc.

Some Paracord Projects

Knots used in paracord projects are often the same ones used in macrame projects. Check your mom's book case for her old macrame projects. The cobra knot of the paracord crowd is exactly the same knot as the old macrame square knot. Project Gutenberg has some books on this. Here is one: Macrame Chapter in an old book.

This link is from the Internet Archive This macrame book can be borrowed for 14 days.

The Open library. org also has books available on macrame.

I've used paracord for many things around the boats. One of the most successful paracord project was a lot of bumpers I made for my Skerry.

I found that the commercial bumpers I could find, that were small enough to be useful on the Skerry, were quite rigid and tended to dent the plywood. I made some from pool noodles and paracord. I made a first lot, and although it worked I found that they were a bit on the skinny side. I made a second lot that worked much better. If you make these, consider using UV protected cord. Nylon has a good UV resistance.

My Skerry weight about 150 pounds with all the rigging plus my weight, so it does not need a very substantial bumper. The bumper on the left was my first experiment. I don't think it would take much abuse and the core is sensitive to UV light when not protected. It has lasted 2 seasons without damage and has worked except it was just a bit too thin. A big bump would crush it, so I made a second version using thicker pool noodles, instructions below. They worked very well.

Simple Small Boat Bumper, 2 Versions

bumper version 1 bumper version 1

Both version start the same way with shaping the noodle so the edges are rounded. I used a bread knife that had small serrations.

bumper version 1starting

To get started you need to make a loop. I just used an overhand knot to tighten it. You then need to cast on as many strings as you need. It should be in multiples of 4 dangly bits = 2 long bits. Don' forget the ends of the loop count as 2 dangly bits. I think the bumper would have been better with at least 4 more down lines, than I put on. This would have covered the inside core better. I used 8 long ropes (including the one I used for the loop), which are cast on in the middle so 16 ends dangle down. It's a bit tricky to predict the length of each rope. I used 48 inch lengths (which means that each dangly end is only 24 inches) and that was not quite enough. I had to melt some more string on to lengthen some of the tails.

casting onsquare knot

These are illustrations showing the casting on and square knots I used. They come from on old book offered in the Gutenberg collection.

startingWith string in middle

The next step is to use an length of rope, mine is a piece of an old halyard, 1/2 inch across. Make a big knot at one end and thread it in the hole of the pool noodle. Next thread your loop with the bits of rope onto the big rope and tie the end to a high spot. I used a step ladder.

knotting around starting

Start going around making your square knots (cobra knots). When you get to the bottom make sure your knots are quite close to each other and quite tight.

Remove the rope you used to suspend the bumper, and tuck your ends into the inside of the pool noodle core. I used a clothe hanger to pull the ropes through. At that point you can re insert the rope if it will fit, or use a smaller diameter rope, I tucked the end that was at the bottom in the hole. It was quite tight and held all the little ends in place. Make a knot at the top and all your ends should be out of sight and the bumper usable.

Alternative method

This bumper is actually easier to make than the previous version. It is thicker and the core is better covered. I also made the tie from the same material. It took me a bit more time to make.

bumper version 2starting

Make a loop as above, and cast on as many down lines as you can. I used 20 and that worked well. They don't have to be in any multiples. If you want to make the hanging rope as well, leave 4 longer, by 1 1/3 the finished line of the attachment rope you want.

Take all your dangly lines and thread them though the hole in the core. I found that it was quite tight and used a length of wire to thread the ends through. Make a temporary knot where the ends come out of the core. Later you will braid some of the ends to make the rope that attaches to the boat. For the time being just make an overhand knot. Spread out the vertical lines evenly around the core.

Weaving the filler cord

I have lost the photos of the weaving but this is how I did it. Using a long cord, you just loop the end around each vertical line you have set up. These vertical lines should be evenly distributed along the core.

knotting around starting starting

Just keep going around and around with your long strand. Make sure that the loop faces inward to make a smooth cushion surface.

If your bumper looks very bumpy, you might be looping wrong side out, with the top of the loops sticking out rather than in.

Otherwise, don't worry if you make a mistake in the looping. It will not show much.


At the very top when you begin the weaving, and at the bottom when you end, you will not have enough space to loop the line around the vertical strands. Instead, just weave them up and down as though you were sewing. When you get to the edge of the top you can start looping properly.

Putting some masking tape on the end of the long line makes it easier to insert under the vertical strands.

Mr. Amazon will be pleased to sell you a nice hollow needle that you can use to guide the end of your paracord. 3 Different Size Paracord Lacing Needles by Jig Pro Shop (Blue) In this particular project it's not essential but if you intend to do some of the more complex projects then they will come in useful.

starting starting

In the close-ups of the top and the bottom you can see the lines going through the bottom and coming out of the top.

Once you've woven the whole bumper tie your end to one of the vertical line and tuck the end under the weaving along the core. It will disappear.

At this point you need to decide how many lines you want to use to make the long tie. I used a 4 strand sinnet. Instructions below. You can also use a 3 (or double it up to 6) strand braid.

Knot the lines you are not planning to use and cut them leaving enough of an end to tuck in the ends under the weave against the core. The pressure will keep the ends in place.

Here is a link to my page on braiding the 4 strand sennit.


Some free projects on youtube.

Lots of people have posted projects on you tube, here are a few that I like.

Higher up on the page I included a number of Amazon links which include project books. Have a look at those as well.


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I try to be accurate and check my figures, but mistakes happen. Check the suitability of any material against the technical information provided by the manufacturer.

email me if you find mistakes, I'll fix them and we'll all benefit: Christine