… about strings

All my bows are strictly made out of natural materials. The only admission is the use of metal for take down sleeves, modern glue (epoxy, ca, pva) and modern string material on my bows. Of course, I’ve made strings out of natural materials, as hemp, linen, sinew, rawhide and other stuff. But these materials do not have constant qualities and are a lot more heavier than a modern ff string, which can be produced much faster and are easy available (at least for me) than the natural. So I reserve the natural string materials for selected replica bows and use the ff for the majority of my bows.

After testing some different products with different characteristics and searching in the net for specs my choice is BCY 452 X. Why? It is made out of a mixture of two different fibers, Dynema and Vectran. This compound allows no creep (non-recoverable elongation), but a little stretch (elastic, recoverable elongation). This stretch is an important effect for the longevity of our primitive bows.

Most people think string tension is biggest at full draw, but this not true. String tension is about 2,5x draw weight at brace or nearby and scale down while drawing the bow. This is the reason why most strings break at brace and not at full draw. A single strand of BCY452X holds 70 pounds. Let’s say we go for a 6x secure, so we just need a string made out of 6 strands for a bow up to 70 pounds of draw weight.

As most of my bows are between 40 – 70 pounds, the most strings are made usually out of 2×3 strands – a very thin and light construction. This allows more speed compared to a Dacron string and has a cleaner definite release. I do a double serving where my fingers touch the string for more comfort. The ears are padded with 2×2 pieces of Dacron about 8” long (made out of my old Dacron strings).

The reason for using only 6 strands up to 70 pound bows is the intended stretch of the string when returning to brace. Imagine a single strand of rubber – you can stretch it easily. Now think of 100 strands of parallel rubber – no way to stretch out. The same principle works in a string construction; if you use too many strands you eliminate the intended stretch. I’ve seen breaks even on glass bows, because people made strings out of 18 strands ff – this construction is stiff like a steel cable!!!

There are some good side effects too. First, it saves money, no waste of material. Second, a light string cause higher arrow speed. I have compared B50 strings (14 strands) with 452X (6 strands) and got a difference of about 5 fps, on some higher weight bows even a little more. Third, I like the more definite release on that strings, I feel shooting is much more precise.

To say it short: there are only disadvantages, when using more strands than necessary!

 

 

 

String material:

There are many types of string materials from different companies on the market. They all have different properties, but often there is nothing to read about that on the package. I don’t know why the companies make such a mystery about that.

Here is a sheet about what I found or what I could test out by myself. It is not completed as you see – I simply couldn’t find the missing specs. However, I think you can get a good overview about the common materials.

 

 

 

As said in the string article:

Creep = non-recoverable elongation

Stretch = elastic, recoverable elongation

In a string construction (for selfbows) we have to consider these two different elongations. Creep is what we don’t like. It is the reason for several shortening on Dacron strings when new. Stretch, or better a little stretch is good for our wooden bows when the string comes back from release at fulldraw to brace. In other words, the stretch dampens the string kick.

 

 

Serving:

As said above in the main article I do a double serving (but only where fingers are touching the string). The other half of the serving is only one run (secure for the punching bracelet). My intention is of course to make the string as light in construction as possible.

I begin at about the middle of the intended serving length wrapping upwards (upper limb). When reaching the intended end, I wrapp downwards over the first layer of the serving to the lower end. Here is the process:

Mark the string on the braced bow where the serving should sit. I go 2″ above arrow rest and 4″ below, so total length is about 6″.

 

Fix the serving thread with some masking tape and go around the string 3 or 4 turns in the same direction the string is twisted.

 

Now begin the serving, first a few turns over the beginnining thread, do that by hand with loose serving tool.

 

Once the serving is fixed, go on with the tool.

 

After about 20 or so turns cut off the beginning thread.

 

Go on with the serving tool until you reach the upper end.

 

Now you have to serve downwards. Make a brake with your thumb nail, that causes the thread riding upon the first layer and serving downwards (to the left in the pic).

 

Here is the detail how the second layer is on the first.

 

Reaching the lower end. now cut off the serving thread leaving a rest of about 12″.

 

The rest of the serving thread is behind the string (left), make an ear and lay the thread in front of the string (right). Stop untwisting the thread with your fingers, and pull the thread through th ear.

 

Make 15 – 20 turns in the ear.

 

Begin to twist the ear around the string to complete the serving.

 

Turning the ear around will reduce the inner turns.

 

All the inner turns are gone, the rest of serving thread can beseen about 20 turns to the left. Pull on this thread to reduce the ear to zero.

 

The end thread is now laying under the last 20 or so turns of the serving. Pull strongly to reach a good fix.

 

 

 

Cut off the excess and the serving is ready.

 

 

 

 

 

Knocking point:

I personally do not like the common brass knocks and I find it useful to have a moveable nocking point for bow tuning.

In the sketch above you see the principle how a knocking point can be made – a simple 16” long thread of Dacron, tied on with double overhand knots. Do the first above, the second opposing under the string and repeat for 2 times so that 2×3 knots are forming the knocking point. Be sure that the yarn lies at the right position (tight and layer-by-layer). The remaining two end threads are cut down leaving about ½”. These ends can be melted down with a lighter and the knocking point is completed.

This nocking point is very tough on the string. If needed to move up or down use a pair of pliers, it runs on the string like a nut on a screw.

 

 

Ready for the first knot like sketch above.

 

First knot is on the string, next same on the opposing side.

 

2X3 knots ready, the rest of half an inch will be melted on.

 

First nocking point ready. Tear off masking tape and do the second knocking point in the distance of arrow diameter.

 

Well, I always do two nocking points and nock my arrows between. The self nocks of my arrows are matching with the double served string. I make click on self nocks with a narrow slot. Some of the plastic nocks have also a narrow slot, some not. Then the nocking area has to be upholstered with dental floss for a thicker diameter.

 

Two nocking points finished for use with selfnock arrows (narrow slots).

 

When plastic nocks should be used it is sometimes (belongs on the type of nocks) necessary to thicken up the string between these two nocking points. This can be done with dental floss in the same manner as the nocking points.

 

Cut off the dental floss leaving a rest of half an inch. melt it on with a lighter.

 

Finished with upholstered nocking area for use with plastic nocks.

 

 

 

 

 

 

String ear padding:

My strings are usually 2 bundle strings, mostly 2×3 strands. The ears or loops are padded to thicken up, especially on self nock tips to prevent cutting into the wood. The padding is made with 2×2 strands of cheap Dacron (8” long) padded to the two bundles while making the ears.

Different colors can be used for contrast effect.

Here is a detail pic of 2×2 Dacron pieces for string loop padding:

 

Fur silencers:

Suitable fur has thin leather and soft hair, such as rabbit, otter, muskrat, or squirrel. First, cut a strip of fur about 3 mm wide out fur. Best is using a scalpel, the fur should be tightened on a frame and the cutting should be done “in the air”. This prevents cutting through hairs, which is result when cutting on a table. The strips should be 8-10” long.

 

Two examples of some fur, one is ermine the other muscrat.

 

My method for fixing the fur is hanging on nails with clamps. Some wood leftovers glued on the back makes a good ancor for the clamps.

 

Left hand holds the fur, right is free for cutting. One end of the fur is fixed on a board.

This is a furrier’s knife, industrial razor blades can be clamped in. Very good and simple instrument. Altrenative a scalpell or sharp cutter can be used.

 

The detail shows the split razor blade, clamped in the mouth of the knife.

 

First cut and first strip, about 2-3 mm wide.

 

Ermine strips ready for use, I leave it together and tear off only a pair if needed.

 

A bunch of muscrat and fur silencer strips …

 

Now take your string, hang one loop on a nail or something else. Mark the position where the silencers should be (both sides equal distance from tips) with a piece of masking tape, untwist the string here and make an ear.

 

Insert one end of the fur strip.

 

Wrap the strip around the string while the string is under tension (second person). Be sure to wrap in the right direction, just as the string strands are twisted!

 

Pull the end of the fur strip through the opened strands of the string, just like at the beginning. Pull tight and push end and beginning together. Now brace the bow, the silencers should now tightly on the string. If not, pull on the ends. At least cut off the ends leaving a rest of about 3 mm.

 

Fur silencer finished on the braced bow.

 

 

 

 

 

 

 

 

 

 

 

 

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