BOW AND ARROW HUNTING – JUNE 1985
HOW TO BUILD A BOW WEIGHING SCALE – By C.R. Learn
An Easy and Inexpensive Gadget to Determine What Your Real Bow Draw Weight Is!

WHAT IS THE REAL draw weight of you
and your friend’s bows? You can find out for a
few dollars and time invested, constructing your own
bow weighing scale. It is a bow weighing system, most
of which can be made from cast-off wood and other
parts.

The first item needed tor making a bow weighing system is a good adjustable scale.
There are many models and types and the costs vary. The scale I finally
bought was a Texas Cotton Scale made by Hanson. I opted tor one that had one-pound graduations up to and including one hundred- sixty pounds. Now not many bowhunters or other archers reach this poundage —- perhaps a few elephant hunters — but most of us are happy with seventy or eighty, tops. Now I never want to even try to
pull a 160-pound bow, but I am interested in crossbows and they even go beyond that
range.

You need a vertical or horizontal support tor the scale. l used a piece of two-by-tour
from the scrap pile — actually, l have no scrap pile. It is a kulch pile and will all be
used someday sooner or later for something such as this— cut six-feet long. The
length will vary with the type bows you will test and the pulley system you use.


The two-by-four looked rather ratty but with the aid of a propane torch to burn off
the old latex paint, and a heavy scrubbing with a wire brush, I ended up with a good
looking piece ot wood that had a raised grain. A few coats of polyurethane gloss
finish and I had a stick that looked good.

There are several ways you can rig your system tor drawing the bows. It you have help
and are a weight lifter, you could probably get by using a single pulley to wrap a line
going from the bowstring to the scale and merely pull the rope to weigh the bow. That
doesn’t work tor me.

One system that works well is a simple boat winch. This has a crank handle and
a winch to wrap a rope or nylon line into. Tie off to the scale and merely crank the
weight up on the bow as it draws on the board. Most of these winches have a ratchet

The hoist was another problem, simply solved. It has two long strands of nylon cord
from top and bottom, These would normally be used to tie oft on a limb and to the
legs of a deer or other game while skinning. l drilled a hole in the upper section of
the board about seven inches from the top. The nylon cord was passed through the hole
and over the top, back around and tied oft behind. This allows the hoist tree movement and maximum length for pulling.

The bottom cords of the hoist were tied off around the top hanger bracket oi the
scale. This allows the scale to be moved up or down with ease. The line slips out of the
pulleys with just the weight of the scale and you stop it where you want. The pulling
line, on one side ot the pulley from the top, was tied off on the side by using a roofing
nail to wrap it around to keep the scale a constant distance from the pipe.
That completes the bow- scale weighing system. l added two pieces of angle
iron to the back, one on the board. A section of oak was cut to give me clearance between the board and clamp the other piece of iron into the vise. I now have a solid, vertical support for my weighing system.

To operate, all you need do is to position a bow on the bottom pipe section so it rests
on the grip area. Most bows today have the pistol grip style and the groove at that
point tits nicely on the covered pipe. Pull the bowstring up and over the hook at the
bottom of the scale. You may have to put a bit of tension on the scale by pulling the draw
cord to center the bowstring on the scale hook.

Pull on the lifting cord of the hoist, and the bowstring moves up the board as the
scale shows the weight ofthe bow. If you follow the AMO specifications, you can
measure from the pivot point of the grip area (the point where the grip is positioned
on the pipe) and you will have the draw weight at different draw lengths.

You will find some variations between what other bowhunters tell you they are
shooting at for draw weight and what they actually shoot. I first built a unit like this
many years ago and once took it to a shoot. Most bowhunters were happy to weigh
their bows to see what they were actually pulling. Some of the “big guys” wouldn’t
come near me. We sneaked a heavy bow while one character was sidetracked and
found he wasn’t shooting eighty pounds at all; only fifty-five!

This bow weighing system won’t cost you much cash. The wood and pipe we all
have laying around or know someone who does, so that cost is nothing. The Cotton
Scale will run about twenty dollars, give or take a few bucks, and is offered by
many dealers or in catalogs.

This scale can be calibrated with a set screw so you can get accurate readings.
The hoist system can be found in many sporting goods stores, Better yet, browse
through garage sales and swap meets until you find a hoist or winch that will cost
you almost nothing. <—-<<<

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