Update 3/21/10 Forgot to say why I even wanted to make the thing! Silly me...
Here's a custom belt made from a few "D" rings, some webbing, and a single length of parachute cord. The idea was sparked by a customer of mine who noticed the bit of cord that I keep around my neck for tying things out of my way, keeping baby toys from falling out of the stroller, etc. He was an ex- special forces soldier, and mentioned that they used to make belts and all kinds of things out of paracord so that, in addition to being useful, the item could be unraveled in an emergency. When I got home I found only a couple of designs for such a belt, the best of which were published on stormdrane.blogspot.com/. I found that I had some preconceived notions of what I wanted such a belt to actually do:
1) It must hold up your pants. It's a belt. Preferably it should be able to do this even if you need a piece of cord.
2) It must be able to unravel quickly. Paracord is certainly strong enough to retrieve a friend who has fallen through the ice, so time is a concern (a la Slatt's Rescue Knot bit.ly/8sPMIG which can be very difficult to untie).
2.5) It would be nice to be able to make it quickly, just so that there is no subconscious, "is it gonna be worth it? I mean, I spent 3 days locked in a room to make this thing- how good a friend are they?...)
3) Nobody expects the Spanish Inquisition. Neither would you expect to need to rescue someone from thin ice, so it must be something you can fit through your everyday belt loops (usually 1") and still look good enough that you will actually wear it.
Here is my answer. Looks good, can in fact be made in 15 minutes, unravels without binding in less than 15 seconds, and can be used a bit at a time while still holding up your pants. It can even be assembled with multiple lengths of cord, allowing any piece that you needed to be put back without making a whole new belt!
Step 1: Materials
While this can in fact be done without tools at all, I'm going to use a couple of nails, a hammer, a tape measure, and a needle and thread.
Here's what we'll use:
1) 50-100' Paracord (in case you forgot)
2) 16" of 1" webbing
3) 3 - 1" "D" rings
Step 2: Measure!
Don't lie about the measurement, nobody needs to know that you can fit 100' of cord into a 1" belt unless it saves their life!
Subtract a couple inches so that if you use a bunch of cord your pants will still stay up.
Step 3: Set Up
Put a couple of nails at your measured distance, then put two rings on one nail and one on the other.
Step 4: Wind the Warp
So now the fun begins. Take one end of the cord and pass it under one "D" ring, and over the other. Continue this until the flat side of the "D" is used up, usually resulting in about 6 strands on top and 6 on bottom. Tie the end with a couple of half hitches and work the slack out.
Step 5: Weave the Rest
Here's the secret, a combo of Native American Fingerweaving and crochet. Put your finger between the top and bottom strands near the end with the two rings. Take your other hand and switch each strand from bottom to top or top to bottom, keeping them in order. The crossing of the cords is called the shed.
Next, pass a loop of the running end through the shed, leaving the loop about 2" long. Switch the shed, and pull it snug.
**Update 2/4/10: It seems that some people are having trouble with the actual weaving process. Most likely it is the shed itself which is confusing, and since I've been weaving like this for a long time now, it's just second nature for me. We are merely doing plain weave, where the strands begin with every other one being up, eg. up-down-up-down, etc. A "weft" is pulled through, in this case a loop, which holds the warp threads in that position, and then the order of the warp threads is switched, eg. down-up-down-up, etc. This is the same process as used in many baskets.
Pull another loop through, and pass it also through the loop from the previous step. Pull the slack out of the first loop, and continue
Step 6: Finish Up
When you reach the half hitches, take them out and use the end as part of the nearest strand. This will keep the knot from making a bump in the belt.
Weave as close to the end as possible, then cut the cord and pass the end through the last loop. It can be woven backwards or looped around the threads at the edge.
Sew the webbing around the single ring, and you're done!
Just so you know, I timed the unraveling of this belt (45' of cord) at 14 seconds.