This work for L3 project is really stretching my skillz. Since I am using electronics to control deployment of the parachute, I get to experiment with black powder, that’s gun powder people. Makes me feel like a mad scientist. With this rocket kit, it uses nylon screws to keep the nose cone in place.
As part of my design, I have to determine how much black powder is needed to properly deploy the recovery system. So I need enuff umph to break the shear pins, blast off the nose cone, and eject the parachute. I calculated some rough estimates based on the rocket diameter and tube length, however I did not know how to take into account the shear pins. G recommended a ground test.
Here’s the set-up. The rocket rests on wooden holden with lots of blankets to cushion any parts and protect G’s house from destruction. There are wires leading from the charge in the rocket, hooked up to a battery, with a continuity key/launch button. G’s done this before so has the process down, and all the right equipment to make it easy.
Here’s a video of the ground test http://www.youtube.com/watch?v=pYIZfPW9pY8
Be warned this is my first video, so excuse my lameness. The 2g of black powder was clearly not enuff. I will re-test at Plaster site with 3g.