In recent times D loops have become the standard on Compound bows, there are a number of benefits obtained by using a D-loop over the traditional system with a rope attached to the release device. These benefits are -
- When letting down the arrow will not fall off the string.
- String wear is virtually eliminated because your release rope is no longer attached directly to the string, this increases the life of the string and serving material.
- The string is drawn directly behind the centre of the arrow
There are many configurations that can be used when setting up a D loop it is important that some form of nocking points are used, never attached a D loop to the string without the use of nocking points.
It is also important that the D loop is attached so at fully draw the release device is directly behind the arrow.
This is because with most bow designs the upper part of the bow is shorter than the lower part of the bow. As the arrow is attached to the upper part of the bow and is effectively above the true centre of the bow the loop will want to pull up when at full draw.
It is recommended to always use two nocking point, one above and one below the arrow and attached the D Loop knots above and below each nocking point.
Installing a D Loop
The steps below detail the process for installing a D-loop on a string.
Ideally you should use non-stretch nylon or polyester material designed for the purpose, this material should be about 2 mm in diameter. To start cut a piece of D loop material usually about 110 mm long.
After the material is cut to length, first use your fingertip to fray each end of the material pushing the fibres apart. Once separated use a flame to melt each end you just frayed Image 1.
Melt each end of the D loop material until you make a melted ball about twice the size of the material. Blow out the flame and the small ball will immediately begin to harden.
Next, attach a top nocking point and than a bottom nocking point (ideally using the tie on method, the use of crimp-on nocking points is not recommended.
When attaching nocking points is always recommended to allow an additional space of about 1mm between the nocking points with the nock attached to the string. As the string is drawn the nocking points will close up due to the angle of the string, by allowing an additional 1mm reduces possible pinching of the nock.
1) Take the D-loop material and place it on the left side of the bow string with about a 12 mm of material pointing towards the back of the bowstring Image 2.
2) Wrap the D loop material around the front of the bowstring and bring it back around over itself Image 3.
3) Now wrap the D loop material around the bowstring again and back through the loop you just made Image 4.
5) Now pull the D loop knot tight by pulling on the longer end of the material Image 5
6) The small ball you made earlier will keep the material from pulling through the loop Image 6.
7) Now you are ready to make the bottom knot of the loop. Start with the string material placed on the back side of the bowstring Image 7.
8) Next wrap it around the bowstring passing the long end through the loop you just created Image 8.
9) Next move the long end down and around the front of the bowstring moving the long end through the lower knot Image 9, you have now formed a tiny loop
Now push the beaded end through, Image 10.
Using your release device or special D loop pliers apply pressure to the D loop by pulling the D-loop until it is tight.
Completed D Loop, Image 12
NOTE – For demonstration purposes the pictures above do not have the nocking points attached.