Page 155 - Robot Builder's Bonanza

124 BUILD A MOTORIZED METAL PLATFORM

at many online specialty robotics Web sites, such as
Parallax and Pololu. Cost is only slightly more than
the typical standard servo motor, but they save you
the hassles of modifying the servo yourself.
TinBot’s metal body consists of 20- gauge galva-
nized steel nail plates (see Figure 12-2), intended for
home construction and repair. The Simpson Strong-
tie hardware I’ve listed is a common find at many
home improvement stores, as well as online hard-
ware retailers. If this exact brand is not available, you
can substitute most anything else that matches the
Figure 12-2 Simpson Strong- tie approximate dimensions.
TP35 and TP37 steel nail plates used for
the body of the robot. Note the holes
already drilled into the plates. PREPARING THE METAL PIECES
As noted, the only cutting you need to do is to strip off
a portion from the two LSTA9 straps. Using a hacksaw outfitted with a metal- cutting blade, cut
the straps to a length of 5-1/2″. Use a miter box (see Figure12-3) to ensure a straight cut.
Plastic miter boxes are inexpensive and are very handy for all kinds of robot construction
chores. The cuts don’t need to be perfect, but file down any rough edges that may remain.
Figure 12-4 shows the straps before and after cutting.
With the file still in your hands, use it to round off the edges of the TP37 plate, to remove
the sharp corners.
If you have a pair of metal shears, either hand or power operated, these will make the chore of
G cutting the straps even easier. For best results, first use a hacksaw to score a shallow cut in the
metal, then cut with the shears. Apply a dab of oil on the cutting surfaces to prolong the life of
the tool.

DRILLING HOLES

Though the nailing plates and straps have holes in them, they don’t always match up where
we want them to. Using some holes already in the plates, matching holes are drilled into the

Figure 12-3 You need to cut off
a few inches from the nail straps.
Use a hacksaw (with a sharp blade Figure 12-4 Original and shortened nail
for metalwork) and, for best results, strap pieces. After cutting, file off the metal
a miter box. for a smooth edge.

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