easton-archery easton tune User Manual

Successful tuning can only be achieved by using a prop-
erly spined arrow shaft. Start with a shaft recommended
on Easton’s Arrow Shaft Selection Chart, available on the
Easton web site at www.eastonarchery.com, in the Easton
Target and Bowhunting catalogs, and on the Easton Shaft
Selector “Plus” software program. Final verification is
achieved during the tuning process. Problems caused by
an improperly spined shaft will become evident during
tuning. Before tuning, be sure that shafts are straight,
properly fletched, and have perfectly aligned nocks.

Tuning procedures for the three most popular shooting
setups are described and abbreviated throughout this
guide as follows:
◆ recurve bows, using finger release (RF)

◆ compound bows, using finger release (CF)
◆ compound bows, using a release aid (CR)
Some of the techniques of bow tuning apply to all types of
bow setups and others apply to just one or two types.
When separate tuning procedures are required for specific
setups, find your setup within the topic and follow those
specialized instructions.

Before starting any bow tuning, be sure to install on your
bow all the items you intend to use when shooting. This
includes the correct bowstring, bow sight, stabilizers,
arrow rest, cushion plunger, bow quiver, etc. Any adjust-
ments made to the bow or changes in bow components can
affect the tune of your equipment. Remember, when tuning,
it is very important to change only one variable at a time!

The first phase in achieving well tuned equipment is good
preliminary equipment setup. If the initial setup is done
correctly, bow tuning can be an easy process. By following
the bow setup guidelines in the initial preparation of your
equipment, you can eliminate most or all of the possible
disturbances that cause tuning problems, including false
tuning indicators. An example of a false tuning indicator
would be having a high nocking point indication when the
problem is actually poor clearance.

Install a moveable nocking point on the bowstring. Clamp-
on types are ideal. Initially, position the nocking point on
the bowstring about 

1

/

2

" (1.3 cm) above square for RF and

CF and approximately 

1

/

4

" above square (0.63 cm) for CR.

See Fig. 1.

Bow limb

Bow limb

Tape

Tape

Wheel

Wheel

Balanced
limb center
(left mark)
Measured 

3

/

16

"

from actual
center

Actual
limb center
(right mark)

In order to have a reference point from which to adjust the
arrow's left/right position on the bow, it is necessary to find
and mark the exact center of the limbs on a recurve bow,
or what is termed the “balanced limb center” on a com-
pound bow, as defined below.

To find the limb center for recurve bows, place a
piece of masking tape across the inside of each limb
near the riser. Measure the width of the limbs, and
make a small vertical mark on the tape in the exact

center of each limb.

To find the balanced limb center location for the
preliminary setup of your compound bow, place a
piece of masking tape across the inside of each limb
near the riser. Measure the width of the limbs, and

make a small vertical mark on the tape in the exact center
of each limb. Next, measure 

3

/

16

" (4.8 mm) to the left of the

mark (for right-handed archers) and make a larger vertical
mark on the tape. (Left-handed archers place a larger mark

3

/

16

" (4.8 mm) to the right of the limb center mark.) This

second mark will be used for arrow centering. (See Fig. 2.)
This procedure is done to compensate for the amount the
eccentric wheel or cam is offset from the actual center of

the limb. The 

3

/

16

" (4.8 mm) measurement is an average

“offset” difference for most compound bows and does not
need to be a precise measurement in the preliminary setup
stage, as you will locate the true balanced limb center
when performing the fine-tuning procedures.

The objective of arrow centering is to have the arrow leave
the “theoretical” or “balanced” limb center of the bow. In
actuality, it is the two nodes (Fig. 3) of the arrow shaft that
should leave the center of the bow in direct alignment to
the target. Releasing the string with fingers creates a
horizontal bending motion within the arrow. Releasing
the string with a release aid causes a slight up/down
bending motion. Because of this, the arrows must be
positioned differently for each style of release. Adjust the
horizontal (in/out) position of the cushion plunger or
arrow rest assembly so that the tip (center) of the arrow
point is correctly aligned with the type of equipment you
shoot. (See Node Alignment diagram to the right).

90

°

1

/

2

" RF, CF

1

/

4

" CR