Launch Pad HELLFIRE

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Jeff278

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Here’s and dumb question for a Newbie (Which I am), Where’s the CP for this rocket and how far off from that point should this rocket balance?
And should it balance fully Launch Ready or Empty?
Thanks in advance for your Help!!
 
Good morning. Just laid my hands on a kit sold cheap but missing the manual. Tried to find it but had no luck. Regarding fin size and buildup hints would it be nice to have. Does by chance anyone has the maual or knows where to get it? Mailed the manufacturer also.
Thank you in advance.
 
Actually, your question is a really GOOD one to ask and unfortunately CG and CP (C of Area) are not indicated or talked about in the instructions on most if not all Low Power kits nowadays. Most kits are "fine as is" but occasionally they are not.

I'm not familiar with the "Hellfire" but here goes: Is it small enough (We are in the Low Power Rocketry section) to balance on a string with a loop in the string?

If so, the "swing on a string" test is something I ALWAYS do with Low Power Rockets.
1- install the heaviest motor in that you think you'll use, balance it on the string, repeat this test if you end up with a bigger, heavier motor later.
2- have at least 6ft or more string length to feed out and swing it around you, more string/length is better
3-(a) If it stays "Nose first", you're fine,
(b) if it spins, you're close to neutral-stability, and you probably want to add some weight to the nose, adjust your string to the new balance point, spin again.
(c) if it goes Tail-first and stays that way, you're definitely tail-heavy and definitely need to add weight to the nose, adjust your string to the new balance point and spin again.

***Rockets "can" be Too Nose Heavy but this is rare and usually take some effort.

Sometimes you can hang a rocket in front of a fan, but that often is not reliable due to the turbulence that comes out of most fans unless you make an enclosed wind-tunnel with turbulence reducing grids.

There are those who don't take stock in the "Swing on a string" test, but it's a simple quick low-tech method for small-enough rockets that generally works well. There are other considerations and flight properties affecting flight, RocSim is really good but I'm a low-tech, cheap Luddite.

Hope that helps-Paul
 
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Good morning. Just laid my hands on a kit sold cheap but missing the manual. Tried to find it but had no luck. Regarding fin size and buildup hints would it be nice to have. Does by chance anyone has the maual or knows where to get it? Mailed the manufacturer also.
Thank you in advance.
You're in luck...I have a kit I opened years ago and haven't started. Here's the fin template... I'll message you the directions.
Also these kits are looong OOP, so don't expect to hear from the manufacturer.
IMG_20220704_164353163.jpg
 
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