Model G0900 (Mfd. Since 03/20)
-33-
Pattern Work
When using a pattern, a rub collar or ball bearing
can be positioned 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 shapes oversize and
then shaping the edge in a simple two-step opera-
tion. A pattern, when attached to a workpiece by
adding toggle clamps, hand-holds, or other safety
devices, make a fixture.
Figure 43 shows proper
setup of pattern and bearing rub collar.
You have greater flexibility when choosing the cor-
rect diameter rub collar for pattern work than for
non-pattern work. If you look at
Figure 43, you will
notice that the position of the pattern determines
the depth of cut. In other words, your pattern size
is dependent upon the inter-relationship of the rub
collar cutting diameter, and the desired amount of
material removed. Changing either the cutter or
the rub collar will change the amount of material
removed. Planning ahead, you can best decide
which rub collars are best suited for your applica-
tion.
Always perform test cuts on scrap stock to ensure
pattern works as required.
Rub
Collar
Workpiece
Template
Figure 43. Position of pattern on workpiece and
bearing size determine depth of cut.
Things to consider when making a pattern or
fixture:
•
Use a material that will smoothly follow rub
collar, ball bearing or fence.
•
Secure workpiece to a pattern (on sides that
will not be cut) with toggle clamps, or fasten
with wood screws.
•
Make your fixture stable! Use proven meth-
ods and materials, and attach hand-holds for
operator comfort and safety.
•
Ensure clamps and hidden screws do not
come into contact with cutter.
•
Design your fixture so that all cutting occurs
beneath workpiece.
•
Always consider rub collar diameter for cor-
rect depth-of-cut when designing your pattern.
•
Make sure your workpiece rests flat on work
table, not on work fixture.
•
Remember, there are tremendous cutting
forces involved. Fixtures must be solid and
stable, and any workpiece must be firmly
secured.
Use care in designing and making fixtures.
Clamps and screws cannot touch the cutter,
and the fixtures must be stable in use, with
the workpiece resting on the shaper table,
not on the fixture. The workpiece must be
fixed securely to the jig.
Summary of Contents for G0900
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