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CREATE THE PARTIAL PROTOTPYE
helps you confirm that your CAD and CAM set-
tings will work with your material.
02: Consult “Prototyping” on page 136 and
“Test Pieces” on page 136 about how to work
with test pieces and consult “Partial Prototyp-
ing: Using a Test Piece” on page 212, which
covers how to prepare, cut, and evaluate a test
piece.
FIGURE 10-8
Test piece in context
PREPARE FILE
03: Open the file in SketchUp and scale all of
the 2D parts by S. Select Save As, adding the
percentage to the filename (e.g.
AtFAB_CHR_TEST_9842.skp).
FIGURE 10-9
Test piece on the cut
sheet
PREPARE TOOLPATHS
04: Following the steps in “Job Setup” on page
170, import the scaled test piece file into
VCarve. Locate its parts on a clear area, where
they won’t interfere with the chair parts you
cut later, similar to the layout shown in
Figure 10-9.
05: Define three toolpathing layers:
◦ Outside toolpaths cut around the outside of
all chair parts.
◦ An inside toolpath cuts the slot in the chair
seat.
◦ The holes toolpath for fastener holes uses a
smaller end-mill. Assign the outside and
holes to the test piece.
While the test piece does not use an inside
toolpath, it helps to define it now so that you
can apply it to the actual chair parts later.
When programing the cutting sequence, cut
the fastener holes prior to cutting the outside
profiles (Figure 10-1). This order ensures that
details like the fastener holes will stay aligned
within the parts as they are cut. Since the
fastener holes require an end-mill change, it
also makes sense to position them first in the
cut sequence so that you only need to change a
tool once.
CUT, ASSEMBLE, AND EVALUATE
06: Save the toolpath operations for fabrication
and cut out the parts.
07: Assemble the test piece using Figure 10-8
as a guide.
08: Evaluate the fit. If your test piece joinery is
too loose or too tight or doesn’t match the fit
described in “Cut and Evaluate Fit” on page
201, consult “Troubleshooting” on page 202
for additional techniques and steps for achiev-
ing an optimal fit.
09: Continue cutting test pieces until you are
satisfied with the joinery. Make a note of the
scaling adjustment, and save the final VCarve
10/5-30 MINUTE CHAIR
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