Page 184 - 15 Dangerously Mad Projects for the Evil Genius

Chapter 13 ■ Levitation Machine 161

This sounds difficult, but actually it’s not at all.
The wire will be wrapped around a large bolt and
we will use two bottle caps as the end points to
contain the wire.
The first step in this is to cut the rims off the
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bottle caps so they are just plastic discs about 1 ⁄2
inches (35mm) in diameter. We then need to drill
holes in the center of each disc, the same diameter
as the bolt shaft.
Fit one of the washers up against the head of the
bolt and position the other washer to rest against
the nut, so that the gap the coil will be wound
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about is 1 ⁄4 inches (30mm).
Next, wrap a single layer of tape around the bolt
(Figure 13-3) to protect the enameled wire from
the rough edges of the bolt’s thread.

Step 2. Wind the Coil

About 700 turns of wire will be wound onto the
bolt. Fortunately, we do not need to count the turns
as we add them. If we fill up the space to the right
depth, we should be close enough. We can also
verify this by measuring the resistance of our coil,
which should be between 3 and 5 .

Even better, we do not need to roll each of these
turns by hand. Instead, we can use an electric drill
set at its slowest speed to do it for us. Figure 13-4
shows the arrangement.
Figure 13-2 The anti-gravity machine
The spindle of wire is sitting on a screwdriver
fixed into a vice, but it is equally practical to make
Assembly

The following step-by-step instructions lead you
through making the anti-gravity machine. Most of
the components are either soldered directly to one
another or plugged into the Arduino board, so there
is no need for a circuit board.

Step 1. Create the Coil Former

It’s difficult to get hold of suitable coils for this
Figure 13-3 The bolt and homemade washers
kind of thing, so we are going to wind our own.