Page 126 - Robot Builder's Bonanza

MAKING PLASTIC FRAMES 95

Chamfer corners
Center piece

Assembled base
(glue or fasten)

End pieces
Figure 9-6 If cutting out wheel wells proves difficult with the material or tools you have, you can
achieve the same result by assembling individual rectangular pieces together.

Making Plastic Frames

You read about making full- bodied frames out of wood in Chapter 7, “Working with Wood.”
The majority of plastics available to consumers are rather flexible— this is especially true of
expanded PVC. This makes them less than adequate for the job of creating robot frames.
However, given a thick enough material (I’d say 3/8″ or larger), the flexing is minimized.
You can combine strips of 6mm PVC to make 1/2″ framing material, like that shown in Fig-
ure 9-7. See Chapter 7 on how to use a miter box and backsaw to cut the ends of the frame
pieces to 45°. Assemble using the same kind of flat angle brackets and steel fasteners.

Side view Top view

1/8" thick Combined
strips thickness
3/8"
Be sure to align
the strips before assembly;
smooth out uneven
edges with a sander
Figure 9-7 Pieces of thinner plastic sheets can be rigidized by stacking them several layers deep.
You can make solid bars of plastic, useful for frames, with just a few strips of 1/4″ material.

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