Page 65 - Making things move_ DIY mechanisms for inventors, hobbyists, and artists

46 Making Things Move

To construct structures from wood, make through-holes (holes that go all the way
through the piece) whenever possible, and use nuts and bolts instead of screwing or
nailing directly into the wood and risking a split edge. The farther from an edge the
hole is, the less likely the wood is to split.

Wood glue works very well when two pieces of wood are glued along the grain (not
end to end!). When glued along the grain, the glue has a chance to seep in and grab
onto the straw-like fibers, and will actually reinforce the wood. When glued end to
end, the glue does not have a chance to seep in and grab anything; it just makes a
very weak joint. Keep in mind that wood glues do not accept stains, so be careful not
to leave any glue smudges on your work if you plan to stain the final piece. Natural
woods accept stain much better than composite woods, so keep this in mind if
aesthetics are important to you. See Chapter 3 for more on wood screws and glues.

Paper and Cardboard
Paper, cardboard, and foam-backed boards are also made of wood. Although most
of you might not consider paper an engineering material, you can actually do a lot
with some thick card stock. Just check out the paper animation kits at Flying Pig
(www.flying-pig.co.uk).

Paper or cardboard is also great for quick prototyping to get your head around your
ideas—kind of like LEGOs, but easier to cut. You can even cut out pieces of paper or
cardboard first, and then glue them to your final work material to use as a cutting
guide. Get a good X-Acto (utility) knife, a cutting mat (from an artists’ supply store,
not a kitchen store), and a metal ruler to use as a straight edge. You can substitute
old magazines for a cutting mat, but the mat makes a great work surface in general,
so it’s a good investment.

To find paper and cardboard, your local arts-and-crafts store is a good place to start,
followed by office-supply stores. You can find posterboard and index cards at most
drugstores.