Tune in each month for a heads-up on
where to get all of your “robotics
resources” for the best prices!
The Recycled Robot
There’s an old saying — maybe it’s a
new saying — that goes “Everything
old is new again.” What we used to
throw out in the trash are now
collector’s items people buy and sell on
eBay for top dollar. Popular fashions
that peaked then ebbed in decades
long past and were considered passé,
are now all the rage. Again.
Recycling is something we humans
do by nature. Old things get repurposed inside new ideas. In the case of
mechanical constructions such as
robots, recycling is often cheaper and
usually faster. If you already have it on
hand, it doesn’t cost you any extra, and
it’s available for your immediate use.
Recycled robots is itself a recycled
idea. There’s nothing new in the
concept of constructing robots from
used, surplus pieces. What is new are
the vast resources now available to find
those pieces. Aside from the usual
haunts such as local thrift stores
and the garbage bins behind the
neighborhood light industrial parks,
we now have the Internet — and its
searching features — to locate the best
junk for building recycled ‘bots.
In this month’s Robotics
Resources, we’ll cover a number of
these used parts hot spots, and provide
useful guidance on how to best fill your
robotics parts bin.
Parts and More Parts
The Internet is a vast mail order
catalog, but mail order isn’t the only
(or necessarily the best) way to find
robot bits and pieces. When you buy
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local, not only do you get to see
and touch the item(s) you’re interested
in, you get to have it right then
and there. And, of course, you save on
shipping costs.
Make your first destination the
nearby thrift stores. Most areas have at
least one Goodwill, Salvation Army,
or similar thrift store that accepts
household discards and resells them at
a fraction of their original price. Look
for: VCRs, record players, CD and DVD
players, fax machines, battery-operated
tools (drills, socket wrenches, etc.), and
most anything else powered by small
DC motors. In addition to one or
more motors, inside you’ll often find
wiring, gears, pulleys, belts, and
other mechanical parts useful in robot
building.
You don’t need to worry if what
you’re buying still works; in fact, you
often get the best prices for the old
broken junk. Over the years, I’ve
bought dozens of VCRs — great
sources for small motors and other
precision parts — for a couple of bucks
each. The older the VCR the better,
because it will have more and better
parts to pull out.
Other prime local sources include
garage sales, appliance repair shops
(ask to go through their discard bin),
and dumpsters behind electronic and
mechanical manufacturing businesses.
For the latter, it’s generally not legal to
raid a garbage bin unless it’s on public
property, and most of these are on
private property. So get permission
from the owner first. Be careful of
broken glass and other sharp objects in
the trash. Wear heavy gloves or you’ll
risk getting a serious cut.
Once you’ve exhausted the
neighborhood venues, you can turn to
mail order and the Internet. See the
Sources section that will follow for a
selected list of online retailers that
specialize in used and surplus mechanical parts. But by no means consider
this list as complete. These initial
sources will help give you a general
idea of what’s out there and what
might be useful for the robots you
build. Note what things are called and
the general asking prices. Then broaden your search using Internet engines
such as Google, Yahoo, or MSN.
Remember that there isn’t an
endless supply of used and surplus
merchandise. Quite often, the seller
has only hundreds or perhaps just
dozens of a particular item. The odds
of you looking and finding just the
right part when the seller has them for
sale are not high, so you need to plan
ahead and purchase items for future
projects. The danger in this approach is
getting too excited about all the goodies out there, and spending money on
things you’ll never use. You should limit
buying for the parts bin — as opposed
to making purchases for your current
project — to only low-cost items.
One approach to spreading out
the cost of filling a parts bin is to get
involved with friends. Make group
purchases for a centralized parts bin
that you all have access to. Keep track
of the cost of each item, including a
pro-rated amount for shipping. As
items are taken out by the members of
