Page 67 - Robot Builder's Bonanza

36 GETTING PARTS

• Industrial parts outlets. Some places sell gears, bearings, shafts, motors, and other indus-
trial hardware on a one- piece- at- a- time basis. The penalty: fairly high prices and often the
requirement that you buy a higher quantity of an item than you really need.

Scavenging: Making Do with What You

Already Have

You don’t need to buy new (or used or surplus) to get worthwhile robot parts. In fact, some of
the best parts for hobby robots may already be in your garage or attic. Consider the typical
used VCR. It’ll contain at least one motor— and possibly as many as five— numerous gears,
and other electronic and mechanical odds and ends.
Depending on the brand and when it was made, it could also contain belts and pulleys,
miniature push buttons, infrared light emitting diodes and detectors, and even wire harnesses
with reusable connectors. Any and all of these can be salvaged to help build your robot. All
told, the typical discarded VCR may have over $30 worth of parts in it.

Never throw away small appliances or mechanical devices without taking them apart and
G robbing the good stuff. If you don’t have time to disassemble that CD player that’s been
skipping on all of your compact discs, throw it into a pile for a rainy day when you do have a
free moment.

Likewise, make a point of visiting garage sales and thrift stores from time to time, and look
for parts bonanzas in used— and perhaps nonfunctioning— goods. I regularly scout the local
resale stores and for very little money come away with a trunk full of valuable items that I can
salvage for parts. Goods that are still in functioning order tend to cost more than the broken
stuff, but for robot building the broken stuff is just as good. Be sure to ask the store personnel
if they have any nonworking items they will sell you at a reasonable cost.
Here is just a short list of the electronic and mechanical items to be on the lookout for and
the primary robot- building components they have inside:

• VCRs are perhaps the best single source for parts, and they are in plentiful supply. As
discussed, you’ll find motors, switches, cable harnesses, and other useful goodies.
• CD players have optics you can gut out if your robot uses a specialty vision system. Apart
from the laser diode, CD players have focusing lenses and other optics, as well as miniature
motors.
• Old fax machines contain numerous motors, gears, small switches, and other mechanical
parts.
• Mice, printers, old scanners, disk drives, and other discarded computer add- ons con-
tain valuable optical and mechanical parts. Mice contain optical encoders that you could
use to count the rotations of your robot’s wheels; printers contain motors and gears; disk
drives contain motors; and so on.
• Mechanical toys, especially the motorized variety, can be used either for parts or as a
robot base. When looking at motorized vehicles, favor those that use separate motors for
each drive wheel.

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