40 MAY/JUNE 2017 SPORT ROCKETRY
S C H O O L
R O C K E T
K I T
•Easy Assembly using
"Through-the-wall-fins"
& Pictorial Instructions.
•Ideal first rocket for
Classroom or group
use.(Bulk packs
available.)
•Balsa Nose Cone
& Fins.
•Streamer Recovery for
Small Fields.
•Length: 14",
Diameter: 0.976"
•Recommended Engine:
A8-3.
•Expected Altitude:
300 ft.
www.BalsaMachining.com
$5.25 each in bulk pack format.
Vector Pod
Cut a 2.25" piece of BT-20. Use cyano-
acrylate (CA) (with accelerator) or epoxy to
attach the adapter rings to each end. Cut a
1.75" x 14" orange plastic streamer. Attach
the streamer to the motor tube with UPS or
filament tape.
Cut a 2.75" piece of BT-50. Prepare the
nose cone by cutting off the base at the flat.
Cut a 7/8" disc of 1/32" plywood. Glue the
disc to the base of the nose cone. Coat the
disc with a thin layer of epoxy. Glue the
cone into the end of the tube.
Make the pylon from 1/8" balsa sheet,
2.75" long, 1" high at one end, 7/8" high
at the other end; the grain must grain run
in the vertical direction. It must be pre-
cise, or off-vertical boost will result. Glue
the pylon to BT-50 tube. Verify position to
drawing; the rear of the tube it is point-
ing "down." It helps to put the pylon on
the tube slightly crooked (1/16" offset at
one end)—this will cause a slight spiral on
boost. Epoxy the launch lug to the top of
the BT-50 tube.
Radio system parts for
the RumbleBee-C: Battery
connector, linear servo,
and receiver board.
Detail view of the attachment of the carbon fiber pushrod
to the linear servo using a piece of music wire.