Manual of Purpose-Made Woodworking Joinery

150 Traditional saw sharpening of non- hardpoint saws

necessary) as you continue the shaping operation –

and combine it with close, visual appraisal of the

shape and pitch of the teeth in relation to the shiny,

flat areas on the tips. These flat tips are produced in

the topping operation and will gradually diminish as

the gullets deepen, indicating that the shaping must

stop immediately the shiny tips are removed. Finally,

it helps to rub chalk on the file occasionally to reduce

the tendency of the file to become clogged with metal

particles.

SETTING

Figure 9.3: This next operation, known as setting,

refers to the bending of the upper tips of the teeth,

every other one, out from the face of the saw on one

side and then setting the alternate row of teeth on the

other side. This is done with a pliers- type tool known

Topping tool

Figure 9.1(c): To assist the filing operation, a wooden
block grooved to take the mill file and a wooden
wedge, should be made. The complete assembly,
illustrated in Figure 9.1(c), is known as a topping tool.
Its main advantage lies in keeping the file – by virtue
of the block being pressed against the saw blade – at
right angles to the saw. Finally, it must be borne in
mind that excessive topping creates extra work in the
next operation, shaping.

SHAPING

Figure 9.2(a): The operation of shaping (and sharpen-
ing) is carried out with a saw file. Such files are equi-
laterally triangular (60°), slim- tapered (as illustrated)
in various lengths, single- or double- ended and are
fitted into plastic or wooden saw- file handles. 150mm
double- ended files are recommended for dovetail-,
tenon- and panel- saws and 200mm or 225mm
double- ended files for crosscut- and rip- saws.

Shaping technique

Figures 9.2(b)(c): When shaping, the filing action
is always square across the saw blade and follows in
every consecutive gullet from the heel on the left to
the toe on the right. The idea is to eliminate the dog
teeth and create evenly shaped teeth leaning towards
the toe of the saw at the correct pitch and points- per-
25mm. Pitch refers to the angle- of- lean given to the
front cutting edges of the teeth (as shown at the end
of this chapter). The recommended pitch angle for rip
saws is 87°, for crosscut saws is 80°, and for panel- ,
tenon- and dovetail- saws is 75°. Although these angles
are not critical to a few degrees, until experience is
gained in angle- judgement, the required angle can be
set up on an improvised template or sliding bevel to
test the degree of accuracy in initial shaping.

FILING ACTION

Figures 9.2(c)(d): When filing, the handle should be
held firmly in one hand and the end of the file stead-
ied and weighted with the thumb and first two fingers
of the other hand. All the strokes should be forward-
acting and not drawn backwards. Take great care in
establishing the correct angles and shapes on the
first few teeth and then familiarize yourself with the
feel of the file resting in a corrected gullet. Maintain
this feel (and go back occasionally to regain it, if

A

A–A A

File towards toe

Heel

Heel

Heel

1234 56

(a)

(c)

(b)

(d)

Figure 9.2 (a) Double- ended saw file; (b) Broken

lines indicating the shaping- outline to be judged;

(c) Recommended saw position for shaping sequence;

and (d) the final, shaped appearance.