What "other" types of rockets have you launched?

[jqavins]

Foot on the launch pad, hook the double-handed sling to the two hooks at the top. Stretch the bands as far as you could reach---make sure it did NOT point toward your face!---and ease pressure on the pad. A hook at the bottom of the rocket would slide out of its slot and the thing would fling itself hundreds of feet up.

Hedgehog space program.

Doesn't really count as a rocket, but when I was a kid, we would take an expired CO2 cartridge from a BB gun, cut the nozzle off of it with a hacksaw, stuff it full of paper match heads, stick three out of the back as a "fuse", stick the whole thing in a steel pipe, light the "fuse," and let 'er rip. Very exciting.

How does that not count as a rocket? Propulsion by expulsion of gas from onboard combustion, said combustion using both fuel and oxidizer that are on board prior to launch (i.e. not air breathing). That's a rocket.

Two more I want to try but haven't. My father had a tool for puncturing the seal on seltzer bottle cartridges, a spring loaded pin in a tube with a simple hold-back to be released when ready. Insert the cartridge in the bottom of a rocket shaped object or the back or a pinewood derby car. Puncture the cartridge and off it goes. I'd have to remake the tool if I ever get up the time, energy, inclination, and tools all at the same time.

The other is another form of water rocket based on the dry ice bomb. Score a circle in the middle of the bottle cap so that it breaks out before the bottle bursts, but not too much before. Tape cardboard fins to the bottle for good performance, and tuck a launch lug under the label.

 

[NateB]

My first rocket was a little plastic water rocket with the hand pump. My son has a stomp rocket which you can see in my avatar. I've also made matchstick rockets, rockets powered by vinegar and baking soda, firework rockets ranging from the normal small bottle rockets to ones with 1" cored BP and whistle motors and 6' long sticks.

 

[Bat-mite]

How does that not count as a rocket? Propulsion by expulsion of gas from onboard combustion, said combustion using both fuel and oxidizer that are on board prior to launch (i.e. not air breathing). That's a rocket.

Well, there was no intention to achieve stability. There was no vehicle. It would be the same as putting a motor in a motor tube and igniting it. I don't think that qualifies as a rocket.

 

[prfesser]

Almost forgot one...

In grad school there was a guy who filled a plastic soda bottle about half-full of water, took it outside, dumped in some liquid nitrogen, turned it upside down, let go. The pressure from the vaporizing LN2 gave it good thrust. Went up about five feet...then went sideways. And the ice that formed clogged the "nozzle". The boom was pretty loud; one of the postdocs from India stuck his head out a window, eyes wide and staring and frantically asking "What was that? What was that?"

 

[NateB]

I took a rocketry summer school class in 6th grade. The instructor was one of the middle school science teachers and he attempt the same demonstration with a 2 liter bottle rocket with cardboard fins, a paper nosecone and filled partially with liquid nitrogen.

It didn't fly at all, it just expanded rapidly with an impressive boom and cloud of steam. We were inside watching out the window and the room full of us young boys were giddy. The dog groomer across the street was less impressed.

 

[viney266]

I had that Estes hydrogen power thing. My one and only attempt at using it was unsuccessful. It ended up in a Goodwill donation.

I bought that for my kids and if we followed the instructions to the letter it worked perfectly. It provided them with a summer or two of fun. They didn't go very high.

 

[Grog6]

A place I worked that did high vacuum stuff gave me the opportunity to participate in several non-standard rockets.
LN2 is such fun I saw a 5 gallon Dewar go out the garage door one day, still headed up, thru freezing up the opening temporarily, until it broke, fell over, and launched.
The best one was the valve and about 6" of pipe attached, that used to be the vent on a 250 liter dewar; someone shut off the "obvious leak" It clearanced a foot-wide hole in the roof, and was never seen again, lol.
The best one tho, was hydraulic; some Mechanical Phd's were making a test fixture, and got a piece stuck inside a housing, so they filled it with oil, and hit another passage with 250psi air. It left the building thru a wall and took a couple of windows out of one of their cars. 5 lb piston was not found. I calculated the hydraulic leverage was about 100:1. It was a miracle no one was seriously injured in those.


One I haven't tried yet: (Probably a good thing)
Most people don't know that LN2 is colder than LOX, so if you blow air into LN2, LOX will form in the bottom.
Another rarely known fact is that LOX is magnetic, so you can pull it out with a magnet; aluminum in HCl makes lot's of Hydrogen...

 

[Alan R]

Oh boy...
I built one of these back in the early 00's out of PVC and cable ties. Hooked up to a 12v electric pump. Pump 150lbs of pressure into a 2-liter bottle with a half tennis ball on top. It would go about 200' or so.
I even built one rocket complete with fins and a parachute bay but it was eaten by a tree during a public demo.
I also had this ... a really big rocket that I used to drive around ...

 

[cerving]

And of course, don't forget the Vashon Freon rockets, which were bought by Estes and marked as "Cold Power". Still one of the coolest model rockets ever (no pun intended...)

 

[Alan R]

oooh @Grog6 reminded me of this other one...
This one time, at summer camp ... we had a big fire in a barrel. My friend tossed in an old spray can. Instead of blowing up it launched just like a rocket about 100' or so.

 

[smstachwick]

Film canister rockets and water rockets. Both very fun but it’s much less common to turn those into highly technical and sophisticated things.

 

[Dotini]

When I was a small boy of about 10, I launched numerous gutter rockets.
These were made from a length of steel plumbing pipe (with one end capped) stuffed with zinc dust and sulphur, as I recall. My friend Barry and I would set them off in the street gutter, and they would hopefully skitter several hundred feet without leaving the gutter. Needless to say, I was raised with minimal adult supervision.