Sky and Telescope - September 2017 - 70

ASTRONOMER'S WORKBENCH by Jerry Oltion

A Simple Observing Stool, Plus
EVERY AMATEUR ASTRONOMER

needs something to sit on. Those of us
who do star parties often need something for kids to stand on. We also need
something to carry our gear in. And
it's nice to have a visual guide to help
locate our scopes in the dark.
Australian ATM Tony Morris has
answered all these needs with a single
project: a multi-purpose seat/stand/
storage compartment/marker light.
Tony says, "I ﬁnd that far more than
half of my viewing time is spent poring
over my star atlas, checking my viewing

plans and making notes. I need to be
sitting down. As the design of my stool
took shape in my head, I could see that
the seat could also serve as a storage
container and homing beacon to guide
me between my truck and telescope."
Practicality, utility, durability, and
functionality were uppermost in his
mind. He also wanted it to be light,
strong, and stable. That led him to a
three-legged design to ensure stability on uneven surfaces. This in turn
steered him toward a triangular seat
that required less complicated cutting

Tony Morris with his multi-purpose
seat/stand/storage compartment/
homing beacon.

70

S E P T E M B E R 2 0 1 7 * SK Y & TELESCOPE

of materials than if he had decided
on a hexagonal shape.
He started by cutting the sides of
the box, using half-inch-thick particle
board, and gussets for the corners (both
top and bottom) out of 1.4-inch particle
board. He screwed and glued those pieces
together, then added the feet, which are
made of 1-by-2-inch hollow steel tubing that he splayed outward slightly to
improve stability. He didn't have to bend
the tubing; he simply mounted the legs
at an angle when he drilled the holes to
bolt them in place. He usually observes
on hard ground, so he hasn't had to plug
the feet yet, but he plans to do that with
angle iron when necessary.
The ﬂoor of the box is Masonite,
and the lid is ¾-inch particle board
edged with angle aluminum. The edging
extends below the outer sides of the box
and keeps the lid from slipping sideways.
The triangular box gives the stool
strength and rigidity. It easily supports
Tony's weight with no wobble. The stool
weighs 15 lbs. when empty, light enough
to carry easily but heavy enough to not
tip over when you bump against it.
Tony painted it glossy white inside
and out to increase visibility of the
accessories he stores in it and to keep
from tripping over it in the dark, but his
observing site is dark enough that that
wasn't quite enough. That led him to
the idea of lighting it from within and
drilling holes in the sides and top so the
light could shine outward.
The light is simply a jumbo red (10
mm) LED mounted through a hole in
a small piece of Perspex acrylic sheet
taped to a 9-volt battery. A little experimentation led him to use a 420-Ohm
resistor in series to drive the LED with
the optimal light output. Tony reports
that "under very dark conditions when
my pupils have dilated sufﬁciently, I can

TON Y M ORRIS

Build the Swiss Army Knife of observing stools.
Sky and Telescope - September 2017

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