I use 6-inch
lengths of styrene plastic square stock to retain the parallel boosters. After drilling
small holes in the plastic and roughing up the body tube with sandpaper and a #11 blade, I
attached the plastic stock with 90-minute epoxy.
The payload bay is a 10-inch piece of BT-70 tube
and the nose cone is a balsa tube I got in an ebay auction lot. I glued an Apogee
Components bulkhead and centering ring four inches from the bottom to create a parachute
bay. I glued a loop of 300 lb kevlar line to the bulkhead with 90-minute epoxy to
which I would attach the recovery system.
The parallel boosters consist of 6 3/4 inch
lengths of BT-60 (from a Patriot kit), two Deuce nose cones (one from the kit and one from
my Secret Santa parts package), and two motor mounts (again from Secret Santa package). The motor mount is installed so that the motor
will be flush with the bottom of the booster when launched.
More about this when I describe the booster retention system.
The key feature of the boosters is the
mounting system. The mounts consist of
two-inch pieces of plastic stock which nest inside the plastic stock on the sustainer. The two-inch stock is mounted on a one-inch piece
of sheet styrene stand off that is the same width and thickness as the square stock.
Launch Lug Alignment:
I used 3/16-inch launch lugs. The upper lug is
glued to the BT-70 tube and the lower lug is glued to the fin as shown below.
Body Tube Wrap:
The payload tube is finished with a wrap of
white label paper. I used MS PowerPoint to create a 10" X 7" box in which I
placed the graphics. NASA for obvious reasons, FlisKits the prime contractor, Boeing and
Lockheed Martin the subs, Apogee for component and simulation support, and Estes for
propulsion. The BT-70 tube has a circumference of seven inches so this went relatively
Booster Retention System:
The most unique feature of this model is the
positive retention system designed to keep booster attached in the event that they light
late or not at all. The system consists of two wire nails inserted into each booster,
CAd and epoxy puttied into place. I then tie a small loop of beading elastic to an
18 loop of sewing thread. The thread is attached to the top of the styrene stock on
the sustainer, led under the booster, and the beading thread loop is attached to the two
nails. The elastic takes the slack out of the thread loop and holds it in place until the
motor exhaust burns through the thread. I attach the thread-elastic loops with the motor
in place and run the thread beneath the nozzle and hold it in place with the plastic
ignitor cap Motor thrust holds the boosters in place and at burn out they fall away and
deploy 12-inch mylar parachutes.
Below is a schematic that shows the retention system:
First flight was on a pair of central C6-7s and
C5-3 motors in the boosters. Boost was moderately slow and the rocket turned slightly into
the 5-8 mph breeze. The long burn of C5-3s kept the boosters attached until near apogee
and they separated and deployed their chutes. The C6-7 delay was a little too long as the
sustainer arched over and headed down. Ejection was a couple seconds after apogee and the
24-inch mylar cute brought the sustainer to a good landing. Only damage was a chip from
one fin due to landing on hard turned earth. For the next flight Ill use C6-5s and
Although I didnt use all the parts that
came in the Deuces Wild kit, I did launch the parts I didnt use in the payload
Link to a full size
picture of the finished model.