Wednesday, September 5, 2018

Vashon Valkyrie II Build, Part 11, How's It Work?

There's been a few questions about how the Vashon rockets operate.
For a manual launch: 
The plug is pushed into the nozzle. The "Safety Pin" is pushed through small holes in the plastic nozzle extension, locking the plug in place.
The rocket is filled with Freon while venting off  pressure allowing the engine to be completely filled.
When ready, the safety pin is pulled, the plug blows out and the rocket is launched. You are right next to the rocket when the pin is pulled.

For the electric launch - 
A thin wire is wrapped around the gray lead wire at the base of the plug. The wire is held by friction between the nozzle and plastic nozzle extension. The safety pin is slid in place.
After the rocket is filled, the pin is slid out. The plug is still held in place by the wire.
When ready, the lead wires are touched to a battery. The wire is melted, the plug blows out and the rocket is launched. The electric launch allows you to be farther away from the rocket when launching.

The separator/timer is another matter.
When the rocket is being filled, gas pressure expands a "spring" (formed piece of flat spring steel) that grips the inside edge of the parachute tube.

The rocket is launched. The pressure expanding the spring decreases and the parachute tube falls off. No ejection charge, just cross your fingers and hope the parachute falls out and opens up.

Between the engine and the separator module are paper "timer disks". Start with three disks. Add or remove a disk to increase the delay from 3 to 5 seconds after boost until the parachute tube falls off.

2 comments:

  1. So that's how those worked - always wondered how they arranged to deploy the 'chute from something that started out pressurized. Ingenious. Thanks for showing us that. Wouldn't a large but soft spring above the 'chute help ensure that it came out? Wouldn't take much.

    I remember going into Levine's in downtown C'Springs in (probably) 1976 to spend my birthday money on a cold power product and was talked out of it by the guy behind the counter; "the EPA is banning the propellant so you'll have a shelf queen." Or words to that effect - don't waste your money!

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    Replies
    1. Hi Tim,
      Estes used a spring in their "cold power convertibles" line of rockets. The problem was (and the thing I hated) the spring was always out when the rocket was on the shelf. It looked like a broken toy. The spring was only in the rocket when pressurized and during the boost phase.

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