Sawing terms
Rip sawing Cutting along the
direction of the wood fibres, with
the grain.
Crosscutting Cutting across or
at an angle to the wood fibres,
across the grain.
Kerf This is the saw cut and
therefore equal to the width of the
teeth or the overall width of the
set of the teeth. Although thinner
blades tend to cut faster, they may
also bend under excessive side
loads, creating a wider or deviating
kerf.
a cut
above the rest
Trends product development manager, Neil McMillan, offers
advice on what to look for when buying circular sawblades.
Neil is a qualified wood
machinist, who has
written many articles
on routing.
by Neil McMillan
sing the latest design and
production technology,
circular sawblades are now
available in a wide range of tooth
configurations for cutting all natural
timbers and wood based products, as
well as non ferrous metals, plastics
and other materials. Each tooth
configuration offers different cutting
characteristics to suit various
performance requirements, such as
fast or slow feed rates, in fine and
coarse materials.
U
It is not only the teeth of a circular
sawblade that play a role in its
performance, but the saw plate itself
needs to be designed and produced
to specific criteria to avoid distortion
due to flexing and friction when
cutting. The combination of both the
tooth and plate design must also take
into account other factors such as
waste material dispersion, heat
expansion and noise reduction. Only
by taking all these factors and other
criteria into account at the design
stage, can a circular sawblade be
expected to produce an accurate
18
INProfile
Top bevel clearance (a) Determines how cleanly the blade
cuts and enables gradual penetration
into material.
a
8°-12°
precise cut and an acceptable
standard of finish on the cut surfaces.
The Trend WAVEFORM® range of
Tungsten Carbide Tipped sawblades is
aimed at the professional user and
has been designed for high
performance and reliability, while
remaining cost effective. The
sawblades are available to fit virtually
all current ranges of portable,
crosscut, radial arm, bench mitre,
table and bench saws. Diameters of
blades range from 150mm up to
400mm, with tooth forms and teeth
numbers to suit most applications
required by woodworkers, builders,
carpenters, machinists and other
craftsmen.
1°-2°
b
Radial side angle (b) Ensures clearance between teeth and
kerf side.
Hook or rake angle (c) Angle of tilt of the tip.
- Positive (forward) for ripping.
- Negative (backward) for cross cutting.
- Zero for plastics and aluminium.
c
Top clearance angle (d) Ground according to hardness of
12° to 15°
material to be cut.
d
Tooth pitch (e) Dimension between two teeth and
denotes number of teeth. Smaller
the pitch, greater the number of
teeth.
e
-6° to +22°