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Introduction
Bow
strings are probably the easiest thing that can be manufactured or
customised for a bow. The most commonly used string is the continuous loop that most people are
using
for recurve and compound bows. There are other types, one of which
is called "Flemish Twist" (usually used on traditional longbows, and for now that's
where we will leave it) We will only concentrate on the former.
Following are a few things that you will need to get started:
1.
String Material
The
type of bowstring material that you use is entirely up to you. But
please make sure that your bow is designed to take the bow string that
you are about to use.
Most older bows with wood or wood/glass limbs are
not designed to take the performance strings such as Fast Flight, BCY
450, etc and Dacron is the preferred choice for these older
or lightly constructed recurve bows.
Dacron
is also used for compound bows where the cables are still made of
steel. Kevlar although well known as a bow
string material is generally no longer in use and is not now
recommended.
Fast
Flight and it's equivalents are a must for today's high performing
recurve bows and for the string and cable systems of nearly all compound
bows.
Besides
getting your preferred bow string material, It is strongly recommend to
get some Dacron string material for practice purposes. Dacron
strings are relatively cheap compared to other string materials and can
be used to make your first practice strings.
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| DACRON B-50 |
FASTFLIGHT |
KEVLAR |
BCY 450 |
2.
String Jig
You
will need a string jig. Commercial jigs such as the Arten string jig
(see below) are available from pro-shops and dealers. This is an easily
portable telescopic jig allowing you to change the
length of string.
You can also build your own string jig (and probably
make a more sturdy one) but we will not
go into details at this point.
A sturdy jig is important to get the even
tension in the bow string that you are making.

Bow
String Jig
3.
Serving Material
Serving
materials are available in many colours and types. The most commonly
used types are braided nylon, monofilament and Fast Flight. Other materials
such as Dyneema are also available. These materials are used to end your
string loops and make the centre serving, while protecting your string from crushing.
For
recurve bow strings Fast Flight is a good choice for the centre serving
and braided nylon for the end loops.
For
compound bow strings and cables Fast Flight is recommended for wheel wrap
around end loops and centre serving. Monofilament & braided nylon may also be
considered for the centre serving.
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| No.4 BRAIDED NYLON |
No.18 MONOFILAMENT |
FLASTFIGHT SERVING |
4.
String Serving Jig
String
serving jigs provide constant tension when laying your serving material. It
is a handy tool and any archer who is seriously considering making bow
strings should invest in one.
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STRING
SERVER JIG WITH
YELLOW
DYNEEMA SERVING |
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Now that you have all the materials ready, we can start making the bow
string.
Step 1 : Determine Bow String Length
If you already have a string for your bow, untwist the string and
measure its length. Otherwise determine the length of your bow.
For a recurve bow your
string length should be about 3.5" shorter than your bow length.
Hence, if you are using a 68" bow, your string length should be
about 64.5". For compound bow strings and cables measure from
existing ones that you wish to replace or check the manufacturers
specifications, these are usually indicated on face of the lower limb
near the riser.
It is advisable to add about 1/4'' to the determined string or cable
length in order to allow for some twisting.
Step
2 : Determine Bow String Strand
A
bow string is made up of several strands of bow string material. The
number of strands to use will depend on the material that you choose and
also your bow weight. To find your recommended number of strand, you may
use the following formula:
40lbs
x 4
10lbs
=
16 strands
Therefore,
if your peak bow weight is 40lbs and your string has breaking strain of
10lbs (i.e.. your string breaks if you put a force of 10lbs on it), your
recommended number of strand is:
The
above is a way you could determine your string size. But often people
don't actually go that far to determine their bow string size . The number of recommended strands to use are likely to
be available from the archery pro shop where you buy your string material or
perhaps from people in your club and of course the internet. From the
recommended strand size you may add or reduce 1 to 2 strands to suit
your shooting style and if it's for club training equipment then
durability will also be an important factor.
Below
is a sample of string size that you could use for some of the string
material in the market. (recurve bows only)
For
compound strings and cables it is best to stick to the manufacturers original
number of strands + or - 1 or 2.
Note:
Adding more strands to your string will make it stronger but reduces
arrow speed.
Bow
Weight |
Number
Of Strands (revurve bows) |
| Dacron |
Fast
Flight |
S4 |
BCY
450 |
20
- 25 lbs
25 - 35 lbs
35 - 45 lbs
45 - 55 lbs |
8
10
12
14 |
14
16
18
20 |
7
8
9
10 |
10
12
14
16 |
* The number of strands shown acts only as a guide.
Step 3 : Setting Up Bow String Jig
Before proceeding to set up your bow string jig, lets look at the
basic anatomy of a string jig.

Figure 3.1
A telescopic string jig is shown above. The centre column of
this jig is made up of at least two parts which are fixed together by a locking bolt.
The length of the jig may be adjusted by sliding the two columns up and down and
securing it with the locking bolt.
The 4 winding posts, labelled A,B,C and D above can be rotated at the pivot points shown. This is to allow the 4 posts to
be aligned in a straight line (Figure 3.2).

Figure 3.2
Adjust the jig to the string length that you want to build and
secure the locking bolt. Note : The string length is measured from the far left of post A
to the far right of post D.
Step 4 : Laying the String
Now that your jig is all set up, you can start laying your string
material.

Figure 4.1
1.Find the running end of your string material (thread) and
tie it to winding post A
2. Wind the thread around winding posts A and D until you
have the required number of strands. Keep in mind that one complete loop (A to D to A) is 2 strands.
Keep the
thread as evenly tensioned as you can while winding around the posts.
3.
Once you have wound the number of strands you want, carefully untie the thread end on post A and tie it to the
other end of the thread.
Don't let the tension in the string
go slack while tying the two ends together.
Step 5 : Measure The Loop
By now you have your bow string layed in the string jig. The
next step is to serve the loop (the groves at the end of your limbs). Different bow limbs may have different loop sizes. To
measure yours, take a piece of string and loop it around the limb grove between point X and Y (Figure 5.1). Mark the string
for points X and Y and measure the distance. This is your loop size.
Figure 5.1
Most limbs will have loop size between 2.5" (60 mm) to 3.5"
(85 mm). You may also want to consider making one loop bigger than the other.
This makes identifying which end goes
to which limb simpler. Have you ever strung your string upside down? That is just one of the practical reason for having
different loop sizes. The other is that when you string your bow, you usually place one loop over the limb grove and the other
you slide into the limb.
One of the loops has to be bigger so that it can fit the broader section of your limb. While the other end,
if made too big will cause it to "wander" off the grove easily.
Step 6 : Serving The Loop
Rotate the winding posts A/B and C/D carefully back to the
original position.
Try to even the tension while rotating the posts.

Figure 6.1
Mark the centre point between posts A and B (Figure 6.2).
Once you have found the centre, mark the loop position.
Hence, if your loop size is 3", mark 1.5" to the left and right of
the centre point (labelled 1 and 2 below).
Ensure that
the knot you made is within 0.5" from the end of the loop
serving.
Figure 6.2
You may now start to serve the loop. Start serving
approximately quarter of an inch (6 mm) to the left of point 1
and finish one eighth of an inch (3 mm) to the right of point 2.
This additional serving acts as an overlap when finishing the
end (explained later).
Figure 6.3
Pull a length of serving thread from the spool and lay about an
inch (25 mm) over your bow string.
Figure 6.4
Serve about 10 to 15 turns of serving thread by going over and
under the bow string and the 1"
(25mm) of serving thread. Slowly pull
the "First End" to tighten the serving.
Make sure that
the serving starts at the location quarter of an inch from your
mark
(Figure 6.3).
Figure 6.5
Continue using your string server until the
end.
1.
Cut the serving thread and secure it to the serving (on the
string) using a drop of super glue; or
2.
Don't cut the serving thread. Take a small piece of sticky
tape and secure the end of the serving (stop serving from
unwinding).
Figure 6.6
Slowly turn the posts A and B so that they are parallel to the
centre column. Pull your string so that the serving will have an
eight of an inch overlap. Please refer to the diagram below.
Notice that the end with the serving spool is one eight of an
inch shorter. Next, cut off the thread of the first end that is
sticking out from the serving.
Figure 6.7
You can now start to tie the loop. Pull your serving thread from
the spool and start winding it approximately one eight of an
inch from the end of the shorter serving (Figure 6.8). This is the
reason why we serve the additional quarter an inch at the start
and an eighth of an inch at the end.
Figure 6.8
The manner to serve will be the same as what you did earlier
(Figure 6.5). Continue to serve for approximately 3.5" (see
Figure 6.9). At this point you have to prepare the serving to be
ended by a "blind end".
Figure 6.9
Take a piece of scrap bow string or serving thread about 4" -
6" (10cm - 15cm) long. Place the scrap string over the area
where you are about to serve as in Figure 6.10 below.
Continue to serve as usual for about 10 to 15 turns or for about
another quarter of an inch.
Figure 6.10
Once you have finished serving, pull an additional 2" - 3" from
the spool and cut. Take the running end of this serving and
place it inside the loop of the scrap string. Gently but firmly pull
the scrap string. Your serving end will be pulled together with
the scrap string. Once the serving end is pulled through, pull it
gently to tighten your serving. Cut off the excess serving string
that is sticking out and you're done.
Figure 6.11
Now continue to do the same on for the other loop end
ie.
between posts C and D.
Step 7 : Centre Serving (Nocking Point)
To serve the middle of the string or the
centre serving, It is
usually best to take the bow string off the jig and string it to the bow.
Before stringing it, twist your string for about 10 to 15 turns. This will shorten your string close enough to your normal
bracing height. Using a bow square, mark your nocking point on the string. Then mark two additional points. One at
1.5" (5 cm) above the nocking point and the other at least 3" (8 cm) below the nocking point. Serve between these two points. If
you prefer, you may serve longer or shorter than this recommended length.

Figure 7.1
Please refer to "Step 6: Serving The Loop" for instructions on
serving.
Step 8 : Finishing The String
Before using the string for the first time, rub it with some wax.
Using a piece of rag or leather, rub the string vigorously (not roughly!). The heat generated from the rubbing will soften the
wax and protect the string. Do not wax the serving. If you accidently get any on the
centre serving, sprinkle some talcum powder over it. The last thing you want is a finger tab
or release aid ropes or jaws sticking to the string!
Bow strings making requires only a little practice to master.
Archers who are serious about their shooting should learn how
to make their own strings. You can control the quality of your string better compared to those that you purchase. Here, I
have tried to explain the procedure of making a bow string in eight steps. I just hope I haven't made it look so complicated
and scare you would be string makers out there. It really is simple!
Things to note:
1.
If you have to turn your string for more than 20 turns to get to your bracing height, then your string is too long. On
average, 15 twists is equivalent to about half an inch. Hence, if you have to turn your string for 30 turns, shorten
your string length by half an inch. (15 turns in the string is normal)
2. If your string is too short, do not try shooting with it. Short
string will stress your limbs and may even cause it to break.
3.
Always check your string before stringing for any fraying or defects. If in doubt, do NOT use the string. Light fraying
can most of the times be fixed by waxing your string. A clean, waxed and well cared string will serve you for a
longer period.
4.
Always follow the manufacturer's guidelines on the recommended life span of the string. If you think that you
can only be bothered to make one bow string a year, then please don't choose strings with short life span such as
Kevlar and Vectran.
!! GOOD LUCK !!
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