Mid powered rocket challenges

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mbecks

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I'm graduating on to mid powered rockets but have run into some difficulties. Iv'e only built a mid powered rocket around an E9 so that could be my issue right there. The issues I'm having are because the motors are so heavy I have to ad weight to the nose cone to make it stable. With all the extra weight my bigger E9 goes no higher than a D12. As seen here: https://www.rocketryforum.com/showt...g-some-friends-excited-about-rocketry-(video)

with th that said is all I need to do to over come this is go for a higher thrust?
 

dhbarr

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I'm graduating on to mid powered rockets but have run into some difficulties. Iv'e only built a mid powered rocket around an E9 so that could be my issue right there. The issues I'm having are because the motors are so heavy I have to ad weight to the nose cone to make it stable. With all the extra weight my bigger E9 goes no higher than a D12. As seen here: https://www.rocketryforum.com/showt...g-some-friends-excited-about-rocketry-(video)

with th that said is all I need to do to over come this is go for a higher thrust?
It's a balancing act, literally. More details about your mid-powered builds ( such as how much they weigh and the surface area of your fins ) would be good starting points.

I can also recommend you find a somewhat local NAR and/or TRA section to meet with other interested and interesting people. Even if you decide not to go back, you should have a pretty good time :)

Cheers!
-dh.

PS: Check out OpenRocket
 

TopRamen

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It depends. I do a lot of the lower end MPR stuff, but I would never consider a BP E motor for any of my rockets because their of thrust curve.
If I'm going to use a motor that weighs what the BP E motors do, I'll just use a composite that will safely fly my rocket.
Most of my MPR models, (TLP Style rockets), need a little nose weight because they have wings, and while a few of them would fly safely but low on a D12, an Black Powder E would not cut it.
The best example of this would be the TAN-SAM, which uses a cluster of 2 24mm motors. The added initial weight of the BP E motors is enough to lower the velocity both off the rail and to apogee, that even a 3 second delay would be too long, and my rocket would come in like it did when I used D's with the 5 second delay, deploying its gear too late to fully slow down. It flies great on D12-3's.
 
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Cabernut

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I was wondering what you were up to... It's cool that you're sharing with others.

Another way to add stability is to make the rocket longer as well. Moves the CG and CP farther apart.

I'll 2nd on the OR recommendation. Tinkering with OpenRocket would be a useful tool at this point. Use the right tool for the job. As you go higher in power you will need to know ahead of time where the CP is as well as rod clearance velocity, etc.
 

mbecks

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Dhbarr
i tried contacting both by phone and email several times CAR which is the Canadian version of NAR, so unfortunately I think my local branch no longer exists. That means I get to make it up a bit more which is fun as well.

Cabernut
Im a heavy duty mechanics but started school a while ago to further my apprenticeship so unfortunately my usual good Income is nil while in school that's why my content has slowed considerably. I'm starting on a rocket powered hydroplaning boat so that should be fun once it's in full swing.
I have some nice long tubes so I think I'll try a long rocket with a e12 and see how that goes. Guess I got to build a bigger launch rod now to. It will be a fun summer.
Mad for open rocket I prefer to stay away from so ware use. I realize it's a great tool but is just not the way I enjoy challenging my self.
 

DavidMcCann

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E9's really need a long skinny rocket. It's a specialized motor, not general purpose like D12's. I wish Estes was more clear about that, but they pretty much just market it as "moar powah"
 

dhbarr

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mbecks

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Edited

dhbarr

Uhhh yes you are correct I made a mistake. Following that link my memory was jarred as to what happened. I just tried to send several emails but it has one of those anti bot things where you type in the word you see. No matter how careful I am it says "test string did not match". Even though the word is usually something obvious like "north". It may be a site issue but I'm not to sure either way I cant send the email. give it a try and see if you can get through for me if you would like I'm not sure why I cant get through. thanks.
 
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dhbarr

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dhbarr

Uhhh yes you are correct I made a mistake. Following that link my memory was jarred as to what happened. I just tried to send several emails but it has one of those anti bot things where you type in the word you see. No matter how careful I am it says "test string did not match". Even though the word is usually something obvious like "north". It may be a site issue but I'm not to sure either way I cant send the email. give it a try and see if you can get through for me if you would like I'm not sure why I cant get through. thanks.
I couldn't get the site / form to work, either :-/
 

mbecks

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Oddly I got it to work on my phone, but it won't work on my computer. We will see if I get a response.
 
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