Overhead Water Rocket Launcher Part 1

[mostaphobia]

hello ..... i searched for the PVC pipes , but unfortunately there is no place which sells it :S so i bought the CPVC pipe ...... i know that i can't do that bump with heating because it just melting , so i used a tape to make that bump , it is ok to use the CPVC ?!!

[loganmrlogan]

Thank you for posting this tutorial. Some of us are visual learners and this is exactly what I needed.

If you mentioned the size of the tire stem and I missed it, I apologize in advance. However, from watching the videos, I don't remember the size being mentioned.

If you are following the directions exactly, you should use a 0.453 snap-in valve stem. The other size I've come across is the 5/8 or 0.625 size, which will not fit.

Thank you again for taking the time to make this video.

[cassylandreth]

so like i need all the matierials by tommorow. what do i all need?

[MrTomcarnahan]

Another quick question ... can you recommend good links that tell how to make a simple but reliable "re-entry" system (aka parachute deployment mechanism)?

Fyi .... I am looking at ways to allow filling the bottle with water while it is already on the launch tube and just before pressurization.

[sciencetoymaker]

@MrTomcarnahan You might try something with lawn sprinkler shut off valves for filling with water on the launch pad. As for parachutes, they would seem to be so simple--it was the first science project I made as a young lad--but parachutes are actually very difficult to get to work reliably on water rockets.

Slater

[MrTomcarnahan]

Great tutorial, however I am having problems with the cable tie "hold back" trigger not working and the rocket releasing un-commanded. I have the bump, 8 cable ties, 2inch 1-/2 cover, but the cover does not fit snug over the cable ties and the rocket releases un-commended at 50 psi Any suggestions on improving my trigger to make it more reliable? The 1-1/2 pipe does not feel like it is fitting snug enough against the cable ties to make it sstrong enough ... thus it releases when IT wants to.

[sciencetoymaker]

@MrTomcarnahan I have not seen that problem before. You said "2inch 1/2 cover." Does that mean you used a two and one half inch(2 1/2") pipe? It should be one and one half inch (1 1/2"). That would account for the loose fit. Is that it? Can you send a picture (my regular email contact is at sciencetoymakerDOTorg).

Slater

Do you live in North America?

[MrTomcarnahan]

@sciencetoymaker

There must have been a glitch in the transmission. I used a "one and one half" inch pipe. Yes ... North America. Sorry, I will have to get a digital camera to send a picture. I even tried using more than 8 cable ties to get a snugger fit ... still no good.

[skittlenips]

yes trial and error if there bigger it still tends to go end over end or spiral with a bit of a tail whip and yes ill try to get the launch pad and some launches on by monday allthough my launch pad has a few flaws but its a work in process im currently making a putt putt boat with your tutorials whan i finish i'll have done all of your projects i look forward to seeing more of you videos.

[skittlenips]

I understand what your saying and the videos on now you can see it if you want ya and when it comes down I see what your saying so I try to take alot of precautions such as the stress ball for a nose cone please comment and tell me what you think on my video

[sciencetoymaker]

Well done! Great design and clear presentation! You should now be able to add your video as a video response on this page. You mentioned that the base of the fin must not be more than the diameter of the bottle. Is that based on experiments with bigger fins? What happens if its bigger?

I look forward to seeing your launcher and launches. Keep innovating and sharing!

Slater

[skittlenips]

other than that this video is extremely helpful i'll also post my design of a ground launch pad for a water rocket with this type you can use an air compressor and pressurize it up to 120 psi but i reccommend 100 psi for saftey reasons because the bursting point of these bottles is 180 psi

[skittlenips]

around this problem fill the top bottle or 1 liter bottle with spay foam insulation

IF YOUR STILL CONFUSED I WILL POST A SHORT VIDEO EXPLAINING THIS.

[sciencetoymaker]

It sounds like you're onto some interesting innovations. One caution I have is that a bottle that is more aerodynamic going up is also more aerodynamic coming down--fast enough to break a windshield or injure. That's why I mention water balloons in the video. I think we'd all like to see what you come up with in a video responce. I do ask that you test your ideas, too. Look forward to seening it.

Slater

[skittlenips]

for best results fill 2 liter bottle 5/8 or 1125 ml. also if you duct tape a 1 liter bottle to the 2 liter bottle it is more aero dynamic also if you duct tape something such as a stress ball to the caples 1 liter bottle it preforms better by not flipping end over end. but if you do the these add ons you also must put 3 or 4 congruent fins on the 2 liter bottle and if you do all of these things you'll run into the problem of the top bottle or 1 liter bottle being crushed after landing to get

[joeyo10]

thanks man im doing a scinece project on it over the controversy of how much water to put in ranging from dry run to 3/4 full any suggestions on what to do

[joeyo10]

i modified your design in which the pipe is not the same in the design i have only took into account your idea on the quick release and the bump thank you for replying if i have a leak between one of the tees how do i seal it? from the outside?

[sciencetoymaker]

I've never had a leak in a slip cement joint so I don't know, but I would try the easiest thing first: gobbing some cement on the outside and try to push it as far into the leak as possible.

Slater

[joeyo10]

um i modified ur design and made it shoot diagonal but i got a leak between the joints when i had glued them already what do i do please mail to my youtube account asap bty great tutorial!

[sciencetoymaker]

Do you mean a leak with the tee, end cap or threaded disconnect, or a leak where the rocket seals with the launcher? Be specific.

Slater

[sgtpepper1138]

The Bob Ross of rocket tutorial

great stuff

[xratzix]

Awesome tutorial. Keep up that very good work!

[sciencetoymaker]

Thanks for the encouragement.

Slater

[fireburst08]

excellent instruction.

calm voice.

everyone likes gets sprayed by the rocket lol.

[Ghostkamo]

well put together video

[halfbreedpatriot]

this is good. dude I hear a mild Christopher Walken which makes it even cooler.

[reeferdk]

everybody likes to get sprayed by the rocket... i lolled :D

[Mumblefilms]

I laughed too dude..

[ucerealb]

THXTHXTHXTHX

OMG this is just what I needed...

Oh, and can you update the website instructions? (You made me cut the pipe wrong and buy the wrong joints just to buy them all over again)

;-D

[ucerealb]

THANK YOU 1!!!!1

omg!!1!1!!!!

THat helped so much

[CRZBUILDER]

but this tutorial is very good

[CRZBUILDER]

your hairy hands scare me

[lacone3615]

Excellent. I am going to try this with my students since I teach space science. You don't need to use primer with PVC. Sanding is sufficient before glueing.