Page 120 - Robot Builder's Bonanza

WHERE TO BUY PLASTIC 89

PVC is short for polyvinyl chloride, an extremely versatile plastic best known as the mate-
rial used in freshwater plumbing. Usually processed with white pigment, PVC can be in
any color. Great stuff for robots, especially PVC sheets; much more about this stuff later
in this chapter.

Best Plastics for Robotics

Let’s review the best of these plastics and compare how they are typically used in amateur
robots. And while we’re at it, let’s note how workable— ease of cutting, drilling, and gluing—
each plastic is.

Plastic Typical Robotics Uses Workability Gluability

ABS Base material; small parts Easy to drill and cut Excellent
cut to size and shape
Acrylic Base material; small parts Medium workability; Excellent
cut to size and shape— difficult to cut and drill
however, avoid any without cracking
application where
repeated impact or stress
might cause cracks or
breaks
Polycarbonate Base material Difficult to cut and drill, Good
but not as prone to
cracking as acrylic
HDPE— High Base material; structure Somewhat easy to drill; Poor
Density for framing moderately easy to cut,
Polyethylene but requires power tools
PVC Base material; small parts Very easy to drill and cut Excellent
cut to size and shape

Where to Buy Plastic

Some hardware stores carry plastic, but you’ll be sorely frustrated at their selection. The best
place to look for plastic— in all its styles, shapes, and chemical compositions— is a plastics
specialty store or plastics sign- making shop. Most larger cities have at least one plastics supply
store or sign- making shop that’s open to the public. Look in the Yellow Pages under
Plastics— Retail.
Another useful source is a plastics fabricator. There are actually more of these than retail
plastic stores. They are in business to build merchandise, display racks, and other plastic
items. Although they don’t usually advertise to the general public, most will sell to you, either
full sheets or remnants (ask nicely and they may give you some of their discards). If the fabrica-
tor doesn’t sell new material, ask to buy the leftover scrap.

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