Page 94 - Robot Builder's Bonanza

DRILLING HOLES IN THINGS 63

Figure 6-2 A quick and easy way to Figure 6-3 A counterbore hole is one that
prepare holes of a specific depth is to wrap has two sizes. One use is with lag and wood
a piece of masking tape around the drill bit. screws, where the top of the screw is not
Position the bottom of the tape at the depth threaded. Make the bottom of the hole
of the hole you want to make. smaller to give the threads something to bite.

drill press is the much better tool for ensuring alignment. A basic no- frills bench model is
under $100. I’m still using the one I bought over 30 years ago!

USING CLAMPS AND VISES
When drilling with power tools, exercise care to hold the part in a clamp or vise. Avoid holding
the part just with your hands, especially if it’s small. Why? As you drill, the bit may “dog” into
the material, causing it to get caught. If you’re holding the part, it could get violently yanked
out of your hands, causing injury.
Hold- down clamps and vises come in various shapes, sizes, and styles. There is no one
type that works for every occasion. Spring- loaded clamps (they look like giant tweezers) are
useful for very small parts, while C- clamps are handy for larger chunks of material. A vise is
required when drilling small parts of any type with a drill press. For very small and lightweight
pieces you can use a pair of large lineman’s pliers or a pair of Vise- Grips.

TIPS FOR DRILLING

Here are some handy tips for drilling wood, metal, and plastic. All speeds are in RPM.

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