Page 91 - Robot Builder's Bonanza

60 MECHANICAL CONSTRUCTION TECHNIQUES

Figure 6-1 Learning to read the graduations
of a tape measure is the first step to mastering any
construction project. Most tape measures marked
off in inches have graduations down to 1/16 or
1/32 of an inch.

Read more about how to safely enjoy the robot- building hobby in Chapter 4, “Safety First (and
FYI
Always).”

Plan, Sketch, Measure, Mark

Start with a plan, and take a moment to visualize how your robot will look and the parts that
will go into it. Then,

• Work up a quick budget. If you’re just starting out, you won’t have many parts and sup-
plies. Research what you need (see Appendix A, “RBB Online Support,” and Appendix B,
“Internet Parts Sources”), and make a list of their names, part numbers, and prices.
• Sketch out your plan on paper or by using a computer vector graphics program. I prefer
Inkscape (it’s free).

If you need to cut and drill, mark directly on the materials. For wood, cardboard, and foam-
board use a #2 soft lead pencil. For everything else use a black Sharpie or similar marker; a
fine tip works best.
Use a measuring tape to ensure accuracy. If you’re using a tape measure marked in inches
(see Figure 6-1), the graduations will be every 1/2″, 1/4″, 1/8″, and 1/16″. It’s easy to mis-
count the subdivisions and get the measurement wrong, so double- check every measurement.

Drilling Holes in Things

Except for rapid prototypes (like those in Chapter 14, “Rapid Prototyping Methods,”), most
of your robots will need some holes drilled into them so you can mount things like battery
holders, motors, and electronics.
Regardless of the material (wood, plastic, metal), the basic concepts of drilling are the
same: you put a bit into the drill (hand or power), mark where you want the hole to be, and
drill there. Good drilling involves following some simple procedures, covered here.

PICKING THE RIGHT DRILL BIT
That 29- piece drill bit set you’ve been wanting for your birthday offers a fine selection of
the most common drill sizes you’ll need. But in actual practice you’ll probably end up using

06-chapter-6.indd 60 4/21/11 11:44 AM