Page 86 - Robot Builder's Bonanza

BASIC TOOLS FOR CONSTRUCTING ROBOTS 55

but a ball- peen hammer also works, as long as it’s not too large. You don’t want a sledgeham-
mer when a gentle knock is all you need.

PLIERS
Pliers hold parts while you work with them. A pair each of standard and needle- nose
pliers is enough for 94.5 percent of all jobs. Don’t use either as a wrench for tight-
ening nuts; they’ll slip and round off the corner of the nut, making it harder to
remove later on. Instead, use a nut driver, detailed below.
For heavy- duty applications, purchase a larger pair of needle- nose pliers. A set
of “lineman’s” pliers can be used for the big jobs, and they provide a sharp cutter
for clipping nonhardened wire.

HACKSAW
The hacksaw is the mainstay of robot building. Look for a model that allows quick
blade changes. Common blade sizes are 10″ and 12″ in length. The smaller blade
length is recommended when working with metal. Purchase an assortment of
carbide- tipped blades in 18 and 24 teeth per inch (referred to as tpi, or pitch).
By convention, hacksaw blades are inserted so that the teeth face forward. That means
the saw cuts when you push the blade away from you. However, there is no strict rule about
this. Experiment to see what works best for you.

ELECTRIC DRILL
You use a drill to make holes; an electric drill makes the whole hole process easier.
Pick an electric motorized drill with a 1/4″ or 3/8″ chuck— the chuck is the part
where the drill bit is inserted. Chuck size determines maximum diameter for the
shank of the bit. The vast majority of work on small robots will require bits of 1/4″
or smaller.

G Spring for an adjustable- speed, reversible drill. The slight added price is well worth it. Adjusting
the speed is important when working with different kinds of materials, as some (like metal) need
a slower tool.

DRILL BITS
A drill is what turns a bit; the bit is what actually makes the holes.
So, with that amazingly helpful clarification out of the way, let’s get on with the
advice: purchase a drill bit set in so- called jobber length. In the United States and
other locations where they still use inches, drill bits are measured in fractional sizes. The typi-
cal fractional drill bit set contains 29 bits (give or take), in sizes from 1/16″ to 1/2″, in
64ths- of- an- inch steps. For most robotic creations, you’ll use only a third of these, but it’s nice
to have the full set in case you ever need the others.

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