Page 66 - Robot Builder's Bonanza

GETTING PARTS FROM SPECIALTY STORES 35

While surplus is a great way to stock up on mechanical parts such as big DC motors and
gears, you must shop wisely. Just because the company calls the stuff surplus doesn’t mean
that it’s cheap— or even reasonably priced. A popular item in a surplus catalog may sell for
top dollar, simply because of high demand.

Getting Parts from Specialty Stores

Specialty stores are outlets open to the general public that sell items you won’t find in a regu-
lar hardware or electronic parts store. These don’t include surplus outlets, which were dis-
cussed in the previous section.
What specialty stores are of use to robot builders? Consider:
• Toy stores. Look for construction toys like Erector, Meccano, LEGO, and others. Check
out their battery- operated toy vehicles, such as motorized tanks. Raid the motors and rub-
ber treads, like the ones in Figure 3-2, for your robot. This is how I get parts for most of
my tracked robots.
• Sewing machine repair shops. These are ideal for finding small gears, cams, levers, and
other precision parts. Some shops will sell broken machines to you. Tear them to shreds
and use the parts for your robot.
• Auto parts stores. The independent stores tend to stock more goodies than the national
chains, but both kinds offer surprises in every aisle. Keep an eye out for small switches,
wire, and tools.
• Junkyards. If you’re into building bigger robots, old cars are good sources for powerful DC
motors, which are used to drive windshield wipers, electric windows, and automatic adjust-
able seats (though take note: such motors tend to be terribly inefficient for battery- based
bots).
• Lawn mower sales- service shops. Lawn mowers use all sorts of nifty control cables, wheel
bearings, and assorted odds and ends. Pick up new or used parts for a current project.
• Bicycle sales- service shops. I don’t mean the department store that sells bikes, but a real
professional bicycle shop. Items of interest: control cables, chains, brake calipers, wheels,
sprockets, brake linings, and more.

Figure 3-2 Toys are among the
best sources for robotic parts,
especially motorized military tanks or
construction vehicles. These can be
turned into robots with tracks.

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