Page 88 - Robot Builder's Bonanza

HARDWARE SUPPLIES 57

Driver For Hex Nut
1/4″ #4
5/16″ #6
11/32″ #8
3/8″ #10
7/16″ 1/4″
1/2″ 5/16″

Optional Tools

There are a couple more tools that are nice to have but aren’t absolutely critical to build a
robot. Add them as your budget allows.

• Miter boxes help you make straight and angled cuts into tubing, bars, and other “length-
wise” material. Attach the miter box to your worktable.
• A vise holds parts while you drill, cut, or otherwise torment them. What size vise to get?
One that’s large enough for a 2″ block of wood, metal, or plastic is about right.
• A drill press sits on your workbench or table. It helps you make smoother, more accurate
holes. Lower the bit and drill the hole by turning a crank.

Hardware Supplies

A robot is about 70 percent hardware and 30 percent electronic and electromechanical com-
ponents. Most of your trips for robot parts will be to the local hardware store. The following
sections describe some common items you’ll want to have around your shop.

SCREWS AND NUTS

Screws and nuts are common fasteners used to keep things together. Screws (called
bolts when they’re bigger) and nuts come in various sizes, either in metric or in
imperial (inch) units. For this book I stick with imperial sizes, because that’s still
what we use in the United States, and it’s what I’m used to.
Anyway, here are the very basics of what you should have to build your robots.
You can read more about fasteners in Chapter 13, “Assembly Techniques.”
• Use 4-40 size screws and nuts for the typical tabletop robot. The “4” means it’s a #4 fas-
tener; the “40” means there are 40 threads per inch. Screws come in various lengths, with
3/8″, 1/2″, and 3/4″ being the most useful for small robotics. I use 4-40 1/2″ screws
the most.
• For bigger parts and bigger robots, use 6-32, 8-32, and 10-24 screws and nuts. The most
commonly used screw lengths are 1/2″, 3/4″, 1″, and 1-1/2″. These and other sizes are

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