Rocket Science

Launch 6

This is a Real Player movie of Launch #6 with my very first home-built cable-tie launcher. Things were going so well I thought I'd commit the event to posterity in glorious video...enjoy.

There were 5 test launches prior to this. I couldn't find my bike pump, so I borrowed one from my neighbor. He gave me a nice 12v, 250psi pump with big guage right on the front. He also loaned me his kids for a little while.

The launches scaled up like this:

  1. 16 oz. bottle at 40 psi - straight up, a flawless flight going slightly higher than the roof of the house.

  2. 2-ltr. bottle at 40 psi - about the height of the 16 oz. bottle, it dropped back nicely right in the front yard. My neighbors son pulled the string.

  3. 2-ltr. bottle at 60 psi - I let the neighbors daughter pull the string. She yanked it, the center portion of the launcher tipped over parallel with the legs, the bottle now laying horizontally on the sidewalk... thankfully pointing away from us. I yanked the string so the kids wouldnt go check on it. the bottle travelled down the street to the neighbors drive. the launcher shot back about six feet. Kids got wet. They loved it.

  4. 2-ltr. bottle at 80 psi - after some minor modifications (a couple of screws quickly threaded into the T's) to the launch base so it wouldn't rotate over to horizontal, I pressured the 2-liter to 80 psi, added some fins I had created at one other time and launched a nice shot approx. 100'.

  5. 2-ltr. bottle at 100 psi. - recover and reload, do it again. This one shot considerably higher than the previous and the bottle has been temporarily lost in the backyard or on the roof. If I recover this, I will have a fin detail. Fins were made from another 2-liter bottle section, they're simply cut with a knife and folded out. i have a template for it somewhere. very easy set up.

  6. 16 oz. bottle at 80 psi. - I cant get this bottle pressured over 80 psi. Leak in the bottle? bad o-ring? bad air line seals? leak in the manifold? Dont know yet, I seem to have developed a leak in the system during the last 100 psi launch, the system wont go that high anymore. But that's the least of the problems ... check out the video above, it's kind of amusing.