Shaft
selection tools attempt to select the proper shaft based on the total
energy transferred to the shaft during a shot and the dynamic response
of the shaft to this transfer of energy. Most shaft selection tools
attempt to simplify this selection process by limiting the variables
that the tool adjusts for. There are a number of factors in proper shaft
selection that are simply not addressed by most shaft selection tools on
the market. Just compare the list of variables above to any of the shaft
selection charts available from arrow shaft manufacturers, and it
becomes clear that these charts offer a rough approximation for the
needs for any particular setup.
Archer’s
Advantage provides you with the ability to calculate total stored energy
by adjusting for a wide variety of variables from a Pre-Defined set of
Force Draw Data, or the ability to enter your own Force Draw Data to
obtain the most accurate results possible. Once you have defined the
characteristics of your bow, Archer’s Advantage will automatically
calculate estimated IBO and AMO Speed Ratings and the speed of any
previously selected shaft.
These
Speed Ratings are derived from calculated Total Stored Energy and the
Estimated Bow Efficiency. Archer’s Advantage allows you to adjust the
program’s estimated bow efficiency based on manufacturer’s published
IBO & AMO Speed Ratings or by using user supplied chronograph speeds
along with a known arrow weight.
This
level of customization provides you with the most accurate model of your
bow & arrow’s performance possible, enabling you to select the
proper shaft for your bow with the greatest degree of precision. At this
point, it is important to point out that the spring scales utilized by
most archers and pro-shops are not particularly accurate. I have found
errors as high as 3 pounds in peak weight for bows in the 50 to 55 pound
range. Errors of this magnitude will result in significant uncertainty
when attempting to select the proper shaft to use with your bow.
This
is where calibrating the Bow’s Efficiency using a known Arrow Weight
& Arrow Speed comes in handy. This Calibration Routine provides a
precise measure of how much energy your bow transfers to an arrow shaft.
This significantly reduces the uncertainty in Shaft Selection and allows
Archer’s Advantage to perform shaft selection with unmatched
precision.
You
can also use the Manufacturer’s IBO or AMO rating to calibrate Archer’s
Advantage’s Bow Efficiency Rating. However, this will not produce as
accurate a result as calibrating to your own arrow weight and speed. Due
to the number of variables involved, it is impossible to perfectly match
both Archer’s Advantage’s IBO & AMO speed ratings to
Manufacturer’s published data. If the manufacturer supplies both IBO
and AMO ratings, use the rating that most closely matches your setup to
calibrate the Bow Efficiency Rating.