Page 103 - Robot Builder's Bonanza

72 WORKING WITH WOOD

MEDIUM- DENSITY FIBERBOARD
Medium- density fiberboard (MDF) is a manufactured product, usually available in 4- by 4- or
4- by 8- foot panel sheets, and is made by compressing wood fibers bound with a resin.
There are quite dense MDF panels that are extremely hard and durable, and these are fine
for robot platforms. Others, like particleboard, consist of larger fibers and wood chunks, and
aren’t as strong. Don’t use particleboard for making a robot.
Look for cut pieces of MDF at your home improvement store, so that you don’t have to
purchase an entire sheet. Or find a low- cost paper clipboard at the office supply store. Many
use a highly pressed wood in 1/8″ thickness. Another option is to use those small hardwood
flooring samples they offer at home improvement stores. Great (and cheap!) for small
robots!

G Any downsides to using MDF panels? A few. A 12″ 12″ sheet of 1/4″ MDF can easily weigh
a couple of pounds. And the corners and edges can chip off more readily than with others kinds
of wood. You can keep the corners from chipping if you round them off by sanding or filing.

The Woodcutter’s Art

You don’t need any special tools or techniques to cut wood for a robot platform. The basic
shop cutting tools will suffice: a handsaw, a backsaw, a coping saw— you name it.

• When cutting plywood and wide planking, use a wood handsaw or table saw. You’ll get the
straightest cuts with a table saw.
• When cutting narrow planking or smaller pieces of wood, use a backsaw (my favorite), a
handsaw, or a jigsaw.

Make sure the blade is made for cutting wood. Wood blades have coarser teeth than blades
for metal or plastic. If using a power saw, the combination blade that came with your tool isn’t
the perfect choice for plywood, but it’ll do. Consider replacing it with a plywood- paneling
blade. These have more teeth per inch and produce a smoother cut.
Handsaws come in two versions: crosscut and ripsaw; crosscut is the proper tool for ply-
wood and most of the other woods you’ll be working with.

CUTTING A BASE
The easiest shape of all is square, and that’s what you’ll begin with, even if you plan on a more
elaborate shape. After all, what’s a circle other than a square with lots and lots of corners!
Start with a wooden square or rectangle that’s about the size of the finished base. If you
have them, you can use power tools to make short work out of cutting the wood to the basic
square/rectangle shape.

It’s Not Hip to Be Square
Problem is, square is not the ideal shape for a robot base, because the corners can snag on
things when the bot is driv ing around your living room. You can readily turn the square into
octagons, hexagons, and pentagons simply by lopping off the corners. Unless you’re an
expert at the table saw, do these cuts with hand tools; it’ll provide extra accuracy. Figures 7-2

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