KNSB Rocket Motor Nozzle

[Jonathan Hamilton-Meikle]

Hi,

I visited the site of Nakka Rocketry and tried to use an excel document to figure out the best shaped nozzle for my rocket, but it didn't work for some reason.
Here are my rocket motor specs, maybe you can help me out with how to get the best nozzle design?
- Motor case: 3/4 inch PVC tube
- Length: 9.8 inches
- inner diameter is 3/4 inch, just to clarify
- KNSB (65:35 ratio) motor fuel
- I need it to burn for about 6-8 seconds, so let's not get the pressure too high, but this way I read it can still produce a thrust of around 8 Newtons

What would you guys think about a concrete nozzle? I have a 3D printer, so I could make a very accurate mold for it.

Thanks so much for reading this far down!!!

Best regards,
Jonathan H-M.

 

[gldknght]

It appears you are continuing to try to design and make your own motor at home, contrary to advice you were given in the first thread you started: https://www.rocketryforum.com/threa...otor-around-8-12n-thrust.152427/#post-1881369

You decided not to follow the very good advice given?

In this case, probably no one here is going to want to help you.

In the U.S. what you are doing is dangerous and in most states, illegal due to your age. No one here will help you with something that is illegal here.

 

[Jonathan Hamilton-Meikle]

I thought you meant that ingredients for rockets are not allowed to be advised or given here. I did not know that all in all rocket motors are not allowed.
Now I understand, thanks for clarification!
Btw I don't live in the US

Thanks!

 

[gldknght]

No, you missed my point entirely. What I said was "home made" rocket motors are dangerous, and in the U.S. building home made rocket motors is illegal for anyone under the age of 18. We won't help you do something that is illegal here, regardless of where you live. We also won't help you do something that very likely will get you hurt, even possibly killed, no matter how old you are or where you live.

Why not follow the advice given in your other thread and do things right, and do them safely?