WOODWORKERS' TOOLS AND EQUIPMENT 87 
(2) The rakers or cleaners should be not less than /^ of an 
inch nor more than ^ of an inch shorter than the teeth. 
(3) The form of tooth bevel d(^iK>nds on the character of 
timber that is being sawed. It should not be too flat for sawing 
frozen timber, very hard timber or wood that has many tough 
knots. 
(4) All teeth should be filed to a sharp point. 
(5) Saws require a certain amount of "set, " which is given by 
springing out alternate teeth in one direction and the remainder 
in the opposite direction so that the saw will cut a kerf some- 
what greater than the thickness of the blade. Dense-fibered 
and frozen hardwoods require the least set, while pitchy pine and 
soft broadleaf trees require the maximum. Only the minimum 
set required should be given because the greater the set the 
more power required to pull the saw. Some operators recom- 
mend a set equal to one-fourth the thickness of the blade for hard- 
woods such as maple, birch, beech, and oak, and one-third the 
blade thickness for softwoods such as hemlock, pine and spruce. 
The art of successful saw fitting consists in securing the proper 
balance between the length of the tooth points and that of the 
rakers. In hardwood sawing, the scoring teeth do not sink as 
deep at each stroke as in softwood, and the bevel of the cutting 
points is less acute. Longer rakers can be used with hardwoods 
than with softwoods due to the more shallow scoring by the 
teeth. The raker length should be such that clean-cut shavings 
and not fine dust are produced. When fibers, known as 
"whiskers" adhere to the edge of shavings it is an indication 
that the rakers are cutting below the depth at which the teeth 
have scored the wood, and the rakers, therefore, should be short- 
ened. As a general rule, rakers for hardwoods should be about 
1/64 inch shorter than the teeth points. For softwoods, they 
should be from 1/40 to 1/32 inch shorter. 
Rakers usually are swaged or given a slight bevel on the point, 
since this tends to plane the wood out of the cut rather than to 
drag it out. When sawing hard maple, however, the rakers are 
not swaged because the long strings of sawdust tend to curl up 
in the gullets of the saw and do not readily fall out when the saw 
leaves the cut. 
Successful saw filers often find it necessary to adjust their 
filing practice to the class of labor which is to use the saws. For 
