6 December 2006
Including change 1, 7 December 2006
10-5.2.8 Three methods are normally used to determine if gaffs are properly
10-220.127.116.11 Gaging Method. The gaging method is used to determine the length, width,
and thickness of the gaff and profile of the point. Reference lines are scored on the
gage with slots provided to determine if the gaff length is satisfactory. Most gages also
provide a contour test to determine if the point is properly curved. Openings are
provided for determining if the point is too keen. Each manufacturer makes a gaff gage
to be used with its own climbers. Thus, gaff gages are not usually interchangeable.
Manufacturer's instructions must always be used if available. The "thickness" slot in the
gage is used to measure the thickness of the gaff at 1/2 in (12.7 mm) from the point.
These measurements are made with the outer ridge of the gaff resting flat against the
part of the gage containing the scored lines. If the point of the gaff extends beyond the
farthest line, the gaff is too thin. If it does not reach the nearest line, then it is too thick.
The "width" slot on the gage is used to measure the width 1/2 to 1 in (12.7 to 25.4 mm)
from the point. The same methods and reference line are used in measuring for
thickness. A minimum length reference line is provided, intersecting the thickness
measurements, to determine if the gaff meets minimum lengths.
10-18.104.22.168 Plane Test Method. The plane test method may be used with the gage, or
independently if the gaffs are sharpened by machine process. The test is made by
using a soft board to determine if proper sharpness has been reached. Place the
climber with the gaff side down and parallel to the board without applying downward
pressure above the gaff. Push the climber along the board. If the gaff is properly
contoured and sharpened, it can dig into the wood and hold within approximately 1 in
(25.4 mm). If the climber continues to glide along the board for more than 1 in (25.4
mm), additional honing is required. After the "plane test" has been made, it can be
supplemented by applying a cutout test. Jab the gaff into the board at about a 30-
degree angle for approximately 1/4 in (6 mm). Bring the leg iron down against the wood
while applying forward pressure--one hand holds the leg iron and the other holds the
stirrup. If the gaff cuts out within 3 in (76 mm), it is improperly sharpened.
10-22.214.171.124 Pole Cutout Method. The pole cutout method is used after climbers have
been machine sharpened or gauged (and as often as required thereafter). Perform a
pole cutout test in accordance with Table 10-2 before climbing. Check failed gaffs with
a gaff gauge to determine the reason for failure and correct the deficiency.