Modular rocket test launch

[bugwubber]

Did a test launch of a modular rocket the other evening.
The configuration was 7l total. 2 2l and 2 1.5l all joined with 1/2"cpvc couplers. Attached USWR box fins with VHB double sided tape.

I set the pressure at only 35psi for this test as I wanted to validate whether NBR (falling with style) recovery would work for a larger rocket.

The result was a bit unexpected- what looks like close to 100ft apogee on 35psi. Luckily was able to get it off my neighbor's roof.

The NBR recovery seems to be working so next step is to add the altimeter.

[youtube][/youtube]

[bugwubber]

᤾Guess I should run the simulator first next time. Forgot about this link. http://polyplex.org/rockets/simulation/

[Reptiglorandrockets]

Great launch! Was this your biggest rocket to date? I can't wait to see the rocket fly at full pressure. Do you have a problem with small couplings and a large nozzle?

[ptx]

Did a test launch of a modular rocket the other evening.
The configuration was 7l total. 2 2l and 2 1.5l all joined with 1/2"cpvc couplers. Attached USWR box fins with VHB double sided tape.

I set the pressure at only 35psi for this test as I wanted to validate whether NBR (falling with style) recovery would work for a larger rocket.

The result was a bit unexpected- what looks like close to 100ft apogee on 35psi. Luckily was able to get it off my neighbor's roof.

The NBR recovery seems to be working so next step is to add the altimeter.

Nice night launch. Looking forward to see it at daylight.

[U.S. Water Rockets1]

That video turned out pretty well for such a low light launch! Looks like it was really be spectacular at full pressure!

[bugwubber]

Great launch! Was this your biggest rocket to date? I can't wait to see the rocket fly at full pressure. Do you have a problem with small couplings and a large nozzle?

Thanks. I suppose Something Wicked was the largest for me. 16l, double nozzle rocket ski.

I think what hindered performance on Something Wicked was 1. use of bottom to bottom couplings and 2. the use of lamp rods for all the couplings including the lower ones that water had to pass through.

1/2" CPVC has an internal diameter of .602" or just over 15mm. I'm guessing that lamp rod has an internal diameter of 7.5mm.

So I'm just thinking that if I fill water above the first coupling- say 3 liters, that the rocket may get a bit of a "ramp up" effect to full thrust. That said, 15mm is more than adequate so it should still be a fast launch.

Bugwubber

[bugwubber]

Great launch! Was this your biggest rocket to date? I can't wait to see the rocket fly at full pressure. Do you have a problem with small couplings and a large nozzle?

Thanks. I suppose Something Wicked was the largest for me. 16l, double nozzle rocket ski.

I think what hindered performance on Something Wicked was 1. use of bottom to bottom couplings and 2. the use of lamp rods for all the couplings including the lower ones that water had to pass through.

1/2" CPVC has an internal diameter of .602" or just over 15mm. I'm guessing that lamp rod has an internal diameter of 7.5mm.

So I'm just thinking that if I fill water above the first coupling- say 3 liters, that the rocket may get a bit of a "ramp up" effect to full thrust. That said, 15mm is more than adequate so it should still be a fast launch.

Bugwubber

Actual measurements are 12mm id for CPVC and 7mm for lamp rod.

[bugwubber]

Did a test launch of a modular rocket the other evening.
The configuration was 7l total. 2 2l and 2 1.5l all joined with 1/2"cpvc couplers. Attached USWR box fins with VHB double sided tape.

I set the pressure at only 35psi for this test as I wanted to validate whether NBR (falling with style) recovery would work for a larger rocket.

The result was a bit unexpected- what looks like close to 100ft apogee on 35psi. Luckily was able to get it off my neighbor's roof.

The NBR recovery seems to be working so next step is to add the altimeter.

Nice night launch. Looking forward to see it at daylight.

Thnanks! Unfortunately it turned out to be really windy Sunday so no launches this weekend.

[Blenderite]

I would like to know how you made CPVC couplings to connect the bottles.

[bugwubber]

I would like to know how you made CPVC couplings to connect the bottles.

Here's a crude drawing of it. It is essentially taking the build process of the O-Ring Launcher tube that USWR published but instead of adding an o-ring, you sandwich a bottle and cap in it.

CPVC Coupler.jpg (43.07 KiB) Viewed 32 times

I'll write up a little how to and post it in the tutorials section.

Bugwubber

[U.S. Water Rockets]

I would like to know how you made CPVC couplings to connect the bottles.

Here's a crude drawing of it. It is essentially taking the build process of the O-Ring Launcher tube that USWR published but instead of adding an o-ring, you sandwich a bottle and cap in it.

CPVC Coupler.jpg

I'll write up a little how to and post it in the tutorials section.

Bugwubber

Is that going through the thick plastic of the bottle bottom? That should be very strong and resist flexing if it does.

[bugwubber]

I would like to know how you made CPVC couplings to connect the bottles.

Here's a crude drawing of it. It is essentially taking the build process of the O-Ring Launcher tube that USWR published but instead of adding an o-ring, you sandwich a bottle and cap in it.

CPVC Coupler.jpg

I'll write up a little how to and post it in the tutorials section.

Bugwubber

Is that going through the thick plastic of the bottle bottom? That should be very strong and resist flexing if it does.

Yes a 5/8" hole through bottom center. Had a bit of inspiration hit today. I was able to build and test a new coupling the same day. Will do some more testing before I post the change.



Bugwubber

[U.S. Water Rockets1]

Yes a 5/8" hole through bottom center. Had a bit of inspiration hit today. I was able to build and test a new coupling the same day. Will do some more testing before I post the change.
Bugwubber

Cool! That sounds interesting.