This is a new kit I got as a gift, the BSD 38 Special. Above is the stock kit which consists of nosecone, 10.75" payload bay, 34" booster tube, fins, 38mm motor tube, couplers, bulkheads, centering rings, parachute and assorted hardware.
I had just designed my first scratch build in Rocksim about a month ago with a similar sized rocket and decided to modify this kit for dual deploy with a similar design to my scratch build.
First I took the booster tube and cut it down to 26", with a piece of that left over scratch I cut a 5" section of body tube for the avionics bay. So the new design went to a 3 piece instead of a 2 piece rocket with the center piece being an avionics bay for electronics and dual deployment.
This new design also takes the rocket from 57.75" to 60.5" total length, just under 3 extra inches overall was added to modify for the dual deployment design I wanted.
Next I proceeded with construction, the motor mount was built, fin slots were cut in the booster tube for the stock fins and the motor mount was then installed.
The rear centering ring was left off so that internal fillets can later be applied.
On the other end I installed a piece of 1/4" tubular kevlar for attachment of the recovery system.
Next the through the wall fins were installed. Then internal fillets were applied using Aeropoxy with milled fiberglass.
External fillets were than applied. While these were drying the avionics bay was built.
This bay is a 5" section of body tube with two 6" coupler tubes inserted into it. The key switch used is one that is available from Binder Design, I've used this switch with one of their avionics bay kits and have been very happy with it so I incorporated it in with this bay.
Each end is comprised of a coupler bulkhead plate and an airframe bulkhead plate. The bay is held together by one section of 1/4" all thread. Each end has a 1/4" U-bolt attached for attaching to the recovery harness as well as one electronics terminal for attaching leads to the ejection charges.
The lower section of coupler and bulkheads are epoxied in place, the upper section is not so that it can be slid off to facilitate working on the altimeter, after that is done it is then slid back on and the upper bulkhead assembly is secured via the hardware. The lower section has both the key switch installed into it as well as 3 1/8" ports drilled into it for the altimeter.
Here are the main parts together. The nosecone is held in place for dual deployment by 3 shear pins. The payload section is held to the avionics bay by 3 plastic rivets.
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On the left is the 38 Special completely assembled, and on the right painted and decals applied. Ready to fly, first flights should be this spring, 2005.
Built January 2005.
Diameter 3", Length 60.50" and Weight approximately 60 oz. 38 mm motors and dual deployment recovery.
Maiden flight 8-6-05 at Walcott on an AT J350. Nice flight to 4,943' and dual recovered drogueless to a BSD 45" nylon chute at 500'.
