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2 Stage Baby Bertha

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nomopbo

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It's still nekkid, but here it is. I was inspired by the SemRoc FireFly.
 

OKTurbo

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Kinda funky....

I like it!!

John
 

eugenefl

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What's cool about this design is that the 1st stage will make the liftoff "draggy." I bet once that second stage ignites that BB will kick into turbo mode! Cool design.
 

vsergeev

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Originally posted by nomopbo
It's still nekkid, but here it is. I was inspired by the SemRoc FireFly.
I think it looks awesome!

I just recently bought a baby bertha kit, but now I'm thinking I should have got two. Next time I go to the local rocket shop I'll grab another. I've already seen way too many cool baby bertha mods.
 

gerbs4me

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Awesome:)
you done a great job, lets see that thing in action
 

powderburner

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you should probably add a balsa or spruce laminate with the added grain running spanwise at the main leading edge of the booster, or else laminate the booster fins with card-stock

the existing wood grain is running in a 'weak' direction and will probably snap at touchdown

nice design, looks like it will be a fun flier!
 

cummins

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This is very cool looking. I wish I could come up with cool designs like this.
 

astronboy

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Oh yes, I LOVE that versatile Baby Bertha kit. Although I am building 6 prototype Goonys right now, I have not staged it yet, but I guess that should be next.....

Nice job. My only question is... will the booster tumble, :)
or
lawndart? :(

Fred
 

nomopbo

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Originally posted by powderburner
you should probably add a balsa or spruce laminate with the added grain running spanwise at the main leading edge of the booster, or else laminate the booster fins with card-stock

the existing wood grain is running in a 'weak' direction and will probably snap at touchdown

nice design, looks like it will be a fun flier!
Great Idea! I tried to think about the grain direction and make sure it didnt run parallel with the ground, but I see what you are saying.
 

nomopbo

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Originally posted by astronboy
My only question is... will the booster tumble, :)
or
lawndart? :(

Fred
Good question, I was wondering this myself. I figured the only way to know for sure was GO FOR IT! (and build it strong enough to survive):cool:
How to you figure this out before you build anyway:confused:

Thanks for all the good feedback! It was a fun build. I will let you know how it flies.
 

astronboy

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rocketdad0934

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looks great I like it my question is what does it weight at lift-off? the reason for the question is that I built a neat thing with the fat boy kit only to discover later that the c6-0 is only good for 4 oz and in the transfer the rocket layed over and land sharked into the next hill. may I suggest a 24mm d12-0 might save your wonderful creation. happy flying and many safe recoveries!!!!!:D :)
 

nomopbo

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Another good point. This did cross my mind as I was building the booster to withstand a lawndart incase it didnt tumble! (thicker balsa and a bit of epoxy) (Also nose weight) I dont have a mail scale, so again my attitude was GO FOR IT! We will see come Wednesday.

All good questions, but I am impressed with how much I have learned since I had asked myself all of them. I wish I had a better answer other than "let's see what happens."

I will let you know Wednesday! Wish me luck!:rolleyes:
 

slim_t

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I would think that the Baby Bertha is light enough to be boosted by a C6. It is a good bit lighter than a Fat Boy, as long as the nose weight isn't too much. This is just my opinion though.
You could just get a cheap kitchen scale to weigh it with. They aren't as accurate as a postal scale, but close enough to predict what the rocket will do.

Oh, and there's nothing wrong with the "Go for it" attitude. I do that sometimes to. Some people refer to it as "Experimental", so I usually like to test these designs when I'm alone. :D

Great design by the way.

Tim
 

astronboy

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I agree. I usually test fly new designs alone, even if I designed the rocket using Rocsim. The tough part is getting liftoff photos while launching alone!!

My only criticism, (in a firendly way) is that I believe that a booster should be as light as possible (esp if it might lawn dart in!!). I do not use epoxy on mine, as it adds so much weight. As long as you are not flying on a parking lot, the booster should be OK.

I am curious as to how this little guy flies. Please let us know..... and take some pictures!!!

Boy, that Baby Bertha is great kit-bashing fodder, huh?

Fred
 

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