..know your cutters
Part of the skill of routing is selecting and using the correct cutter
for the job in hand. To produce a quality finish, cutters must be
kept in good condition and be regularly honed.
Straight
The Shank is machined to a
close tolerance to match the
internal diameter of the
collet.
The Flange or Fillet is the
radiused section between the
shank and the cutter body.
Radius
Tungsten carbide tips are brazed onto
a steel body before being ground to
specific cutting angles. The correct
tip and relief angles are essential to
ensure optimum performance.
Flutes are ground into
the cutter body leaving
precise clearances and
relief angles. These
clearances prevent waste
material from packing
between the cutter and
the face of the wood.
Tungsten Carbide
Tungsten carbide tips are used for
most general routing applications as
they retain their edge far longer
than High Speed Steel cutters. They
should always be used for cutting
and trimming abrasive materials
such as MDF, chipboard and other
resin bonded materials and can be
used equally as well on certain
plastics and natural timbers.
Chamfer
Self-guiding cutters are ground to take a
ball bearing guide. The bearing is used
to follow the edge of a template, or the
edge of the work itself, for trimming
and moulding applications.
Ovolo
Feed direction
Feed
direction
Clearance
angle
Material (woodchip, swarf
or wooddust) removed by
each cutting edge
per revolution
Rotation
of cutter
Radial relief
of body
Relief
of tip
Cutting
angle
Gullet
or flute
Rebater
Rake angle
or hook
Always feed the router into the
work against the rotation of the
cutter. This ensures that the cutting
action pulls the side fence or guide
bearing into the edge of the work or
template, preventing it from
wandering and so providing far
Winter 1997
greater control. Feeding the cutter
into the work in the opposite
direction (with the rotation of the
cutter) may cause the router to run
away from you, reducing the control
you have over it.
Dovetail
A selection of
tungsten carbide
tipped cutters from
Trend’s Craft Range
INProfile
5