BOWSTRING BUILDING 101.
You can make your own bowstrings!The making of bowstrings has almost become a lost art. Today, few archers make their own strings, but you can get great satisfaction from making your own strings, and you can custom build strings for peak performance. And even though it may look complicated, building strings is not hard, once you've learned the technique.
String making requires a few basic tools (figure 1). You can buy a commercial string jig or make your own (see index on page 86). Bowstrings used to range in length from 34 to 60 inches, but strings for many new single-cam bows are 96 to 102 inches long, and some commercial string jigs will not adjust long enough to make these strings.
I recommend buying four string-serving jigs two each for different types of center and end servings. Then you need bowstring material. B-50 or Traditional Bowstring by Brownell & Company are good choices for traditional bows and older compounds with teardrop cables. For newer compounds BCY Fibers; Inc. makes 450 Plus, 450 Premium, DynaFlight 97, and DynaFlight 97-8125; and Brownell & Company offers S4, Fast Flight(R) and Fast Flight 2000. All of these are made from low-stretch, minimal-creep, high-tensile-strength fibers.
For servings you also have several choices: From BCY Fibers, Inc. you can get #62 center-serving material in .018, .021, and .025-inch diameters, and #2 thread in .016 and .018-inch diameters for end servings. Brownell & Company produces Braided Center Serving, #3 1/2 Braided, and Monofilament materials for center servings, and #4 Nylon and #2 Fast Flight for end servings. For versatility, get several spools of different center and end serving materials. Finally, a tape measure, cigarette lighter, and small pair of scissors round out the equipment list.
Now you must adjust your jig for string length. If you have an old string, simply put it on the string jig, stretch it tight, and lock down the jig. If you do not have an old string? On traditional bows, bow length should be written on a limb of the bow. If it is not, measure from string notch to string notch (around the curves on a recurve), then subtract 3.5 to 4 inches from the bow length to get string length. Compound bows normally have actual string length written on the lower limb. If this is gone, and you do not have an old string, call the bow manufacturer or an archery pro shop to get string specs.
The following numbered instructions are for making a string out of B50 or Traditional for a recurve or longbow. Modern compound strings require a couple of special procedures, and these will be detailed at the end.
STEPS IN CONSTRUCTING A STRING
1. Select your string and serving materials from the choices listed above.
2. Determine string length and set the jig (figure 2), and decide how many strands are needed. Here are the normal number of strands for each type of material:
Number Product of Strands 450 Plus, 450 Premium 12 S4(R) 10 Fast Flight(R) 20 DynaFlight 97 16 B50, Traditional 12-14
3. Make a slip knot in the end of the string material and slip it over the wing nut that tightens the non-movable swingarm on the jig. Take the strand up and behind the outer swingarm upright, bring it around the groove and go to the outer upright at the other end of the jig. Wrapping from the front of the jig to the back, take the strand around the groove and then back to the other end. Continue to do this until you've laid the desired number of strands. You will end up at the swingarm where you started. To finish off the end, bring the strand on around the outer upright, pull off about 2 1/2 more feet of material, and cut it off. Take that tag end around the inner swingarm upright, drop the tag end down between the front and back halves of the string (between the outer and inner uprights), and wrap the tag end around the wing nut where you started the string (figure 2).
4. Rotate the swingarm on the end where you started the string so it is turned 90 degrees to the base of the string jig. You now have a section of string between the two uprights on which you can serve the end loop. Pull 8 inches of serving material out of the serving jig and lay 6 inches of the material along the string, starting about one-third of the way in from the right upright and laying it towards the left upright. Hold this in place with one hand, and, with the other hand, spin the serving jig around both the string and the tag end you're holding in place to lock the serving down on the string. Serve over the string and serving material for about 2 inches. Now cut off the excess tag end, and continue serving around the string until you've covered about the middle one-third of the string. Tie two half-hitches around the string, cut the serving material leaving a short tag end, and, with the cigarette lighter, melt this tag end and press it into the end of the serving on the string (figures 3, 4, 5, 6, 7).
5. You can now cut the two ends of the string material that you secured to the wing nut to start the string. Leave tag ends on both strands at least 3 inches long from where they come out from under the serving you just completed. Now rotate the jig swingarm so it parallels the jig base.
6. To complete the loop, slide the string around the grooves until the area you just served is around the outer swingarm upright and the ends of the serving are directly opposite each other. Take the two 3-inch tag ends of the string material that are sticking out from under the served area and wrap them around the string, pulling the two halves of the string together. Tuck the ends into the string to keep them in place (figure 8). If the bow limb this loop is going to slide over is 1 1/2 inches wide, you need to make the loop at least 1 3/4 inches long. Pull 6 inches of serving material from the serving jig and lay 4 inches of it down the string over the served area, starting 1 3/4 inches from where the string loops around the upright. With the serving jig, start wrapping towards the center of the string, serving over the 4-inch end, plus the two tag ends of the string material you tucked in earlier. Serve for about 3 inches down the string, then clip off the three tag ends. Continue to serve toward the cen ter of the string for about 6 inches (figure 9).
7. Now you finish the serving with a whip finish. To do this, hold the string tight with one hand where the last loop of the serving material comes off the string. Grasp the serving tool in the other hand and pull about 2 feet of material off the server and take the serving tool about 1 foot towards the center of the string. A loop of serving material should now be hanging below the string. With the string jig, wrap serving material around the string (and inside this loop) back toward the main serving you're holding in place with your other hand, until you have about 10 wraps around the string (figure 5). These wraps should be in the opposite direction in which you served the string.
8. Pull the serving jig towards the end loop to lay some serving material alongside the string. Now continue the main serving by winding the serving material you've been holding in place, tightly around the string and around the wraps of serving material you have taken around the string. You are serving the opposite direction you took the wraps around the string, so that when you have wound 10 loops of serving around the string you will have unwound the 10 loops you made around the string. This will leave you with a loop of serving material about 10 inches long coming out from under the end of the serving. To eliminate this loop and lock down the serving, pull on the serving jig. This will pull the loop material back under the serving. If the loop tangles, place a pencil in the loop and hold it taught as you pull on the serving jig. When the end of the serving is tight, cut the serving material and melt the end down to the string.
9. Repeat this entire process on the other end of the string to form the other string loop. This loop doesn't have to be as long since you won't have to slide it over the limb when the bow is unstrung (figures 6, 7).
10. To do the center serving, put the string on the bow, and draw the bow a few times and, if possible, leave it strung for a couple of hours to get some of the stretch out of the string. Then start the serving about 3 inches above the center of the string on the large-loop end. Serve the center as in the same way you've served the end loops, and lock it down with a whip finish about 4 inches below the center of the string (figure 11).
This describes how to make a Dacron string for a traditional bow. Making a compound bowstring of DynaFlight 97, S4, or one of the other modern materials, which are harder and have less stretch and creep, requires one major change in procedure.
Start the string as described above by dropping a slip knot over the wing nut on one swingarm and then wrapping the desired number of strands around the swingarm uprights. This time, however, instead of taking the finishing end down between the strands and wrapping it around the wing nut, simply clip the starting strand just above the wing nut. Take that end of the string and the finishing end and tie them together with a square knot in the string grove on the outer swingarm upright (figure 12).
It is not necessary to serve the loop itself on modern compound strings unless you just want to. The loops are very small and the material is extremely tough so you can leave the loop strands exposed. However, if you do want to serve the entire loop, the procedure is the same as described above. However, you need to serve only about 2 inches for the loop itself. Remember, the cam pegs these loops go over are relatively small.
If you are going to serve the loop, slide the string around the posts until the knot holding the ends together is just to the right of center between the swingarm uprights. Lay one tag end of the knot along the string to the left, the other to the right. Start your serving as previously described just to the right of the knot, and serve over the knot, working to the left until you've laid down about 1 1/2 inches of serving. Finish this off with two half-hitches, clip the serving, and melt the tag end down to the serving. Slide the string around the uprights until the served area wraps around the outer upright of the swingarm. You are now ready to finish the serving. Start the serving over the loop serving ends as previously described, and serve at least 9 inches down the string below the loop to ensure that all of the string that comes into contact with the cam or wheel is protected with serving.
If you do not want to serve the loop (again, it is not necessary), you can simply slide the string around the uprights until the knot holding the string ends together is about 3/4 inch from the upright (figure 12). Start serving just above the knot, leaving a loop around the upright of about 1/2 inch. You will serve over the knot and tag ends to hold them securely. Again, serve down the string about 9 inches (figure 13). Repeat the process on the other end to finish the end loops. Serve the center as previously described, using braided center-serving material.
You may get frustrated at first, but stick with it. The satisfaction, you get from shooting one of your own custom strings will far outweigh any grief you go through mastering the process. And you'll find it's really pretty easy after all.
The author enjoys building his own bowstrings in Pensacola, Florida.
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| Author: | Atkinson, Jim |
|---|---|
| Publication: | Bowhunter |
| Date: | Jan 1, 2000 |
| Words: | 2116 |
| Previous Article: | ON TRACK. |
| Next Article: | BETTER BOWS THROUGH COMBINED TECHNOLOGY. |