Scratch building BAR

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apburner

APBurner
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So I am a BAR. I was certified to level 2 back around 2000 now I am back. I was going thru a bunch of my old stuff
and found a scratch built rocket I had not flown but was built like a truck so I used it to certify level 1 a few weeks ago.
ugly end veiw postable.jpgUgly side veiw postable.jpg
I t was successful So now it is painted and all pretty LOL. Anyway I have found a 4 inch body tube in my stuff that
already has a 38mm mount installed and it is just begging for some strange fins to go into it. So this is what I have come up with.
I am just beginning to learn open rocket So there may be some flaws in the design. But I think it's pretty close.
Oh also I don't really care about the drag of the holes and they might make this thing whistle reallt loud. :-0
 

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Whoa, those are the craziest fins I've ever seen! What will you make them out of? Your Rocksim file says they're 0.118" cardboard. That can't be right.
 
You're going to glass the fins? Are you going to glass them first then cut them out? I hope you have a scroll saw.

yes I have a scroll saw. I wouldn't attempt those fins any other way. I don't think I will
glass these. though I may throw a layer ofglass on the leading edge.
 
yes I have a scroll saw. I wouldn't attempt those fins any other way. I don't think I will
glass these. though I may throw a layer ofglass on the leading edge.

Personally, I don't think you need to glass these fins if you're using 1/4" birch plywood. Unless you're planning on some extreme motors.
 
Nope not gonna get stupid. This is going to be my altimeter learning bird. I've never used an altimeter and and there for by extension have never done dual deploy either.
So thats what this ones going to be.
 
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Nope not gonna get stupid. This is going to be my altimeter learning bird. I've never used an altimeter and and there for by extension have never done dual deploy either.
So thats what this ones going to be.

Sounds reasonable to me.
 
So I cut my first fin on this thing. Really a simple cut with a scroll saw. But I was thinking. If I take a chisel to the leading side ofr the trailing hole and cut it into the shape of a whistle inlet I might be able to get one whale of a whistle out of this bird. And if I cut all six the same then it will spin fast also because of pressure differential. This could be one of the coolest sounding rockets I've ever made.

flame fin.jpg
 
So I cut my first fin on this thing. Really a simple cut with a scroll saw. But I was thinking. If I take a chisel to the leading side ofr the trailing hole and cut it into the shape of a whistle inlet I might be able to get one whale of a whistle out of this bird. And if I cut all six the same then it will spin fast also because of pressure differential. This could be one of the coolest sounding rockets I've ever made.

Very clean cuts on the fin! It looks great! I'm very curious about your whistle experiment. It'll be interesting to see if chiseling it makes it whistle more. I love it when they whistle!
 
So do I and that is why I am going to give this a try. Also The cuts were very easy. I have been a scrollsawer for many years. And I love to do inside cuts. :)

You're obviously talented with your scroll saw. There is an art to it. It's a skill I never acquired. My best whistler is Tank Girl. I think rockets with split fins tend to whistle more.

[YOUTUBE]EnMFhBn4CYk[/YOUTUBE]


P1010156.JPG
 
So I finally got back to this project for a while and carved out the parts of the fin I wanted to look like a whistle and then painted them red. Well The back of the fin is actually a knife edge with both front and back coming to the middle. But the center is cut all the way to the other side. What do you think. And the paint it just a test it is obviously not finished nor final.

flame fin painted.jpg
 
So I finally got back to this project for a while and carved out the parts of the fin I wanted to look like a whistle and then painted them red. Well The back of the fin is actually a knife edge with both front and back coming to the middle. But the center is cut all the way to the other side. What do you think. And the paint it just a test it is obviously not finished nor final.

View attachment 142373

Wow, way above my cutting skills. Paint job looks a little like tail feathers on Foghorn Leghorn.
 
Paint job looks a little like tail feathers on Foghorn Leghorn.

That is fantastic. I love Foghorn. I would love to hear this thing whistle. But if it just sounds like "Ah Say, Ah Say" That would be OK too. LOL
 
This picture gives a better idea of what I am doing. I wish I new the aerodynamics of a whistle better I could design this thing to scream.
flame fin unpainter.jpg
 
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