Q
RUNNING ON SPIRITS
Using candles for any length of time will coat
the bottom of your boiler with soot and leave
a greasy black ring in your bathtub or sink. To
avoid this, use a spirit lamp. You can make a
simple one by drilling a hole in the metal lid of
a very small glass or metal container, threading
through a lantern wick, then filling the container with denatured alcohol.
the motor in may take a little re-bending of
the tubes. Be careful of hard spots in the
tubes and be ready to re-anneal them.
You can solder the tubes into your boat to
seal them, but it’s easier to just use plumber’s
putty or modeling clay, which you can remove
to make repairs or adjustments.
I’ve also made spirit lamps out of copper pipe
caps and copper tubing. Cut a 1¼" pipe cap
short enough to fit under the boiler with room
for the flame, then sweat-solder it onto a sheet
metal bottom. Drill holes in the cap and solder
in 2 lengths of ¼" tubing: a very short one on
top (the wick holder) and a longer one in the
side (the filling tube and handle), bent upward.
USE IT
To make your boat go, you must first prime
the engine with water.
Turn the boat over and pour water into
one of the tubes until it dribbles out the other
tube. You don’t need to fill the boiler completely: just make sure you can hear water
sloshing around inside. Hold a finger over the
ends of the tubes and lower the boat into the
water without letting any water pour out.
Light candles or a spirit (alcohol) lamp, and
place them under the boiler. In about a minute, you’ll hear the water boiling into steam.
First, a few bubbles will come out, then the
boat will start puttering along in the water,
and as the reaction becomes more vigorous,
the diaphragm will start its obnoxious song.
If the motor stops, blow out the fire, or the
heat may damage the seal of the boiler.
With candles, this engine needs more than
a single small flame to get moving. Use 2 or 3
birthday candles or a tea light with more than
one wick.
Gregory Hayes (lamp)
WARNING: If you blow down one of the boiler
tubes, very hot water can come out the other tube, shooting you in the face with scalding water. Don’t do this —
it will hurt.
William Abernathy ( yourwritereditor.com) is a compulsive
writer, editor, and tinker. He lives in Berkeley, Calif., and flatly
denies tracking metal chips onto your carpet.
See how MAKE Labs engineering intern
Daniel Spangler made a copper pipe alcohol
lamp, at makeprojects.com/v/28.
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