Instructables
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I was making a water rocket. The way I build them is by splicing and making rosin couplings one as a time and testing them. Then I make another one. I tested this one up to 100 psi before and launched it at 70 psi before the failure happened. It failed at only 40 psi. This was a normal launch, so there was about 2 1/3 L of compressed air. The splicing failed. Unfortunately, I didn't get a video of it exploding. I've learned a few things from this experience.
1.Neighbors don't like loud sounds
2. Always film what you are doing
3. Fix leaks (I think the cause of the failure was because there was a tiny leak in the splicing and I was too lazy to fix it
4. 40 psi is a lot of power(see pictures)
5. Get ear protection(I estimate at 100-120 db)
6. Put on payload at last second
if you use glue its allways good to reienforce with tape to make a stronger seal
Lftndbt5 years ago
Ok, I can see what your issue is from the 4 th picture... You left it in the water for too long whilst shrinking it didn't you? The insert end in that pic is just not right at all... We your shrinking it is very very important you do not distort the bottle at all. it looks like it is crumpled and the top leading edge is definatley not square. It appears you were a bit hasty and had the water boiling. or did you use Aircommand method of the blow torch? Now that I am thinking of it, it would be hard to get that much distortion from water shrinking.

Msg me back and I'll help you out.

Check this out if I haven't linked you already. http://leftindoubt.synthasite.com/
Go to my H20 rocket section. Poseidon has 13 spliced joints using sika...
hi, starwing123 (Lui). Nice try on the splicing and coupling. The neighbors must hate you now after like that huge explosion. The splice looks a bit messy, but why is it black glue, don't you use PL premium? It's supposed to be yellow. Good luck on your next launch!
He would have used Sika flex, as I suggested to him.