-28- G8621 Heavy-Duty Sliding Table Shaper
Workpieces must be solid, stable, and
secured to the jig; or kickback may occur,
causing personal injury.
When making a pattern jig here are a few things
to consider:
1. Build your jig from a material that will
smoothly follow the rub collar or fence.
Pattern Work
When using a pattern, the rub collar can be posi-
tioned either above, below or between cutters.
The pattern is usually used when the entire edge
is to be shaped or when many duplicate pieces
are needed. Pattern work is particularly useful
when rough cutting irregular or oversize pieces
and then shaping the edge in a simple two-step
operation. A pattern can be incorporated into a jig
by way of adding toggle clamps, hand holds or
other safety devices.
You have greater flexibility when choosing the
correct diameter rub collar for pattern work than
for non-pattern work. If you look at Figure 41, you
will notice that the position of the pattern deter-
mines the depth of cut. In other words, your pat-
tern size is dependent upon the interrelationship
of the cutting circle, the desired amount of mate-
rial removed, and the rub collar size. Changing
one or more of these will change the amount of
material removed. Planning ahead, you can most
effectively decide which rub collars are best suit-
ed for your application.
2. Make the jig stable, using proven methods
and materials, and fasten the hand holds for
operator comfort and safety.
3. Secure your workpiece on the three sides
that will not be cut with toggle clamps, or fas-
ten the workpiece to the jig with wood
screws.
4. Ensure that clamps and hidden screws do
not come into contact with the cutter.
5. Design your jig so that all cutting occurs
underneath the workpiece as shown in
Figure 42. Notice the operator is not
exposed to the cutting edge of the cutter!
6. Always consider the cutting circle and rub
collar diameter for the correct cutting depth
when designing your pattern.
7. Make sure the workpiece rests flat on the
table, not on the fixture.
Figure 42. Pattern jig for making curved pieces.
Figure 41. Rub collar determines depth of cut.
Pattern
Rub Collar
Irregular or freehand shaping takes a high degree
of skill and dexterity. The fence assembly is not
used during irregular shaping, so rub collars must
be used. Also, unless your jig is designed to
touch the rub collar before contacting the blade, a
starting fixture must be used to begin your cut.
Workpiece fits here