Found this one too, here's the full thread. http://www.huntingnet.com/forum/tech...ts-d-loop.html
I'm now going to give away my biggest secret when it comes to tying D-loops: Don't pre-cut a specific length of material. I see guys all the time say they cut five inches of material to start with, or some other length. I start with the complete length that comes in a package. That way, I can start working from one end, have the rest of the rope to pull with to tighten down my knots, and after I'm through I just cut off the whole excess. I waste NOTHING when I make my D-loops, and am able to really crank down on my knots when I'm tying them.
First, you have to mushroom out one of the ends by tamping down the rope until it flares out...
Take your lighter and melt that flared-out end until it becomes a ball. Most people will tell you not to allow that mushroomed-out part to actually catch fire (to avoid the fibers becoming brittle), but to hold the flame just far enough away so that the fibers melt without lighting. I give the ball 30 seconds or so to cool, and I don't flatten it against the side of the cigarette lighter. Next, I form a loop with the rope and place it under my bowstring like this:
Then, I simply push the melted ball over the string and under the loop, and also feed the long tag end over the bow string and under the loop as well:
Snug up the overhand cinch knot you just created, and rotate it around so that the long tag end is coming off the back of your bow string.
D-loop secret #2: I grab a Mini Mag kept under my workbench, and roll the long tag end around and around the barrel of the flashlight. This allows me to grab it with the tag end emerging between my two middle fingers. While holding the bow string in one hand, I pull as hard as I'm capable of for at least five seconds. This REALLY snugs up this bottom knot! Some people even prefer to wax the rope material, allowing the knot to tighten that much more.
D-loop secret # 3... at least if you're like me and fond of shooting the smallest loop you can get your release in without hitting the arrow nock. With today's "shorty" releases and forward-trigger designs, loop shooters don't have to give up any draw length when combined with this technique! Lay your rope alongside the string and as you make the beginning of your first knot, pull it snug. That's right, don't pre-form a loop. Also, take note to cross your rope over and begin your second knot so that the length of rope passes by the bowstring on the opposite side that it did for the first knot. This will help to prevent the knot from rotating around the bowstring through repeated use. Notice the long tag end coming out of the first knot and what is actually going to form the loop is coming from the bottom of the bowstring; therefore, I cross the bowstring when beginning the second knot OVER the bowstring.
Complete the knot, and again wrap the excess rope material around the Mini Mag... pull until you can't pull any harder.
Cut off the excess rope material, leaving about 1/8 of an inch to flare out so that you can burn it into a ball. I will actually let the ball melt into the knot just barely sometimes to help lock it in. Take care to not allow the fire to melt the actual knot itself and destroy its integrity.
Now you can insert a pair of pliers into the knot, and pull with all your might. This will help cinch the knots down even further, but more importantly will allow you to get your arrow nock into the loop as you draw for the first time with your new loop.
Here's how the finished product looks; note that my release head is directly behind the arrow nock. I had to keep my index finger behind the trigger to show the loop and nocksets, but when I lay it over on the other side and prepare to shoot, I don't feel as though I've given up any draw length, and I feel extremely confident that I'm hooked up as about as perfectly as I can be for that once-in-a-lifetime shot!