Building materials, covering

jander14indoor
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Re: Building materials, covering

Post by jander14indoor »

First, it REALLY isn't that important to have a tight covering. You risk FAR more indistorting your frame than you gain in any smoothness of the covering. And smoothness is HIGHLY overrated, why do you think golf balls have dimples!!

Second, consider a hot hair dryer before you use a lighter. MUCH less likely to burn your helicopter up and easier to control.

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Re: Building materials, covering

Post by thewinner »

Frogger4907 wrote:
Kovu wrote:Whenever we put mylar on it seems to not be as tight as it should be, any suggestions on how to make it tighter?
Hold a lighter under it and slowly move it closer until it tightens, be careful too tight will rip your frame apart, or put a hole right threw the mylar.
NO. The helicopter is made out of (hopefully dry) wood, don't set your house on fire just to make your helicopter look prettier. And, as long as it isn't too loose, having a covering with some amount of give is actually preferable to having it perfectly tight.
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Re: Building materials, covering

Post by Frogger4907 »

thewinner wrote:
Frogger4907 wrote:
Kovu wrote:Whenever we put mylar on it seems to not be as tight as it should be, any suggestions on how to make it tighter?
Hold a lighter under it and slowly move it closer until it tightens, be careful too tight will rip your frame apart, or put a hole right threw the mylar.
NO. The helicopter is made out of (hopefully dry) wood, don't set your house on fire just to make your helicopter look prettier. And, as long as it isn't too loose, having a covering with some amount of give is actually preferable to having it perfectly tight.
Umm yes? it isn't to make it look prettier having it tighter reduces Drag, resulting in longer flight times. The flame would be at least 3 inches from the copter, and unless its soaked in Gasoline, I'm thinking you are going to be dumb enough to light your house on fire.
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Re: Building materials, covering

Post by thewinner »

Yeah, I was kind of exaggerating on the fire part. :lol:
But having the covering have at least a little give is a benefit, since it catches more air that way. And if you have the covering really tight will distort the airfoil, if you are using it in your design.
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Re: Building materials, covering

Post by Frogger4907 »

thewinner wrote:Yeah, I was kind of exaggerating on the fire part. :lol:
But having the covering have at least a little give is a benefit, since it catches more air that way. And if you have the covering really tight will distort the airfoil, if you are using it in your design.
But you shouldn't rely on the lack of tension in the film to develop the air foil, but on the shape of the airfoil you that should be made with the frame.
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Re: Building materials, covering

Post by thewinner »

I know, I'm just saying a little bit of give will provide a higher efficiency for the whole rotor.

Let's stop now.
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Re: Building materials, covering

Post by lllazar »

Ok just some last thoughts on the flim tightness - i actually ran some tests on it and unless your film is really loose, the flight time shouldn't vary that much..Just my two cents, keep it tight (it's quite easy to do, i do this without even using a cradle and my rotors come out close to perfect) but don't fret over tightness...really balance on the rotors is a lot more important.
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Re: Building materials, covering

Post by Sanias »

personally i have been using 1/16*1/16 al the time, and for the covering, i use tracing paper :p
weight reduction to its finest point!!!!
you dont want ur helicpter to be lifting any dead weight so i want to make it as light as possible
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Re: Building materials, covering

Post by illusionist »

1/16 square balsa is also the choice of many of us here. However I think mylar is a better alternative, even though I personally use flimsy grocery bags.
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Re: Building materials, covering

Post by kjhsscioly »

illusionist, which grocery bags do you use, like by store? everything I have seen is too heavy.
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