Hybrid rocket GOx and polyethylene test fire

This rocket was made using steel plumbing parts, copper gas fittings, Gaseous Oxygen from a portable welding kit, and polyethylene tubing; all of which were purchased from Home Depot. The purpose of this test was simply to see I could build a hybrid rocket like the one in eerrp's hardware store hybrid rocket video.
http://www.youtube.com/watch?v=pX4NPKNjSAE

I used a chunk of cotton string coated in nitrocellulose (ping pong balls melted down with acetone) as a kind of fuse to get the rocket started.

Once the rocket got going I could see some cool little shock diamonds that are not visible in the video, but unfortunately the polyethylene melted pretty quick and started clogging off the nozzle. After sputtering for a bit and blowing a few smoke rings the nozzle got clogged the and GOx started coming out the back of the rocket from the copper gas fittings. You can see the molten polyethylene coming out the nozzle near the end of the video.

Category:

Howto & Style

Tags:

• Hybrid
• Rocket
• Rocketmang
• GOx
• Gas
• Gaseous
• Oxygen
• Polyethylene
• test
• fire
• rapid
• combustion
• clogged
• nozzle
• flame
• smoke
• burn

[TheWisey1234]

Where can i find parafin wax

[Rocketmang]

@TheWisey1234

Arts and crafts stores?

Candle stores?

I found mine in big slabs from a crafts store called "Michaels"

[TheWisey1234]

Hey i am wanting to build a rocket with a GPS and a hybrid engine can you give any idea on fuel.

[Rocketmang]

@TheWisey1234

I suggest paraffin wax with a burn stabilizer added.

Just melt it, mix in the stabilizer, and pour it into your mold. (pipe with a rod running though?)

Use powdered charcoal for the stabilizer, not too hard to find/make (fire pits? bbq briquettes?)

Use nitrous oxide or oxygen for your oxidizer.

NOx is available from auto supply stores (a bit safer)

Oxygen from welding supply stores (burns faster, dangerous)

BE SAFE!

Always test rockets in a blast enclosure (see my other videos)

[nedbk]

You realize the only difference between a rocket motor and a pipe-bomb is how quickly the pressure is vented, right?

If the nozzle clogged long enough to let the pressure build up above the rupture strength of the pipe...BOOM!

ALWAYS do tests like this behind a barrier. Don't stand there with a camera watching a pipe-bomb burn!

[Rocketmang]

Thank you for your concern, I do realize the potential risk involved. I have also investigated the burst pressure of schedule 40 steel plumbing pipe and determined that the pipe was in no danger of exploding with the energy invested in this test. In future tests I do employ a blast shield.

[858954]

wow that what i called a perfect fart!!

[drewricomakeubu1]

it needs pepto bismol

[labantolaban]

where could i get polyethylene?

[gazzguy]

i,m a rocket man:(

[wesg77]

i for one will certainly not be going to space on that little thing .!!! i am much too fat , build a bigger one please.

[cheeseboat15]

Too much oxidizer, not enough fuel. However, there was a point when the rocket was performing well