Building techniques

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Littleboy
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Re: Building techniques

Post by Littleboy » April 3rd, 2011, 7:11 am

I have always cut my ribs for wright stuff and never had a problem with it.

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Re: Building techniques

Post by lllazar » April 4th, 2011, 5:21 pm

Lamination of the motor stick is a pretty good idea, i've found, to add more strength to it. For example, i use a 1/8 x 1/4 piece of medium density balsa and then i laminate high density 1/16 x 1/8 balsa to the bottom side. It works like a charm, and btw i use titebond for the lamination, but that's because i have no mass problems and i easily build way under 4g, and titebond III used carefully can add not much more weight than super glue and the bond will be as strong as oak.

Many will say: does it need to be this strong? Well, it's just that i'd rather not risk my helicopter's success to the chance of it breaking at competition :)
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Re: Building techniques

Post by andrewwski » April 4th, 2011, 5:40 pm

Ribs should cut pretty easily out of balsa sheets. Just make sure you have a sharp Xacto blade and don't try to cut through the entire thing at once - make multiple cuts, each one deeper than the last.

1/32" is really easy to cut but also breaks relatively easily. 1/16" takes a little more effort to cut but is pretty strong.

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Re: Building techniques

Post by kjhsscioly » April 4th, 2011, 8:06 pm

I have always found i better to use 1/16th , because the weight lost by using thinner wood doesn't seem enough to justify the weakness. Especially with airfoils because the curve isn't with the grain of the wood.

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Re: Building techniques

Post by genius98 » April 5th, 2011, 5:09 pm

my helicopter only has one side rotating. so far its my best helicopter. but the problem with it is that it dosnt fly long and when it goes up it goes in like a circle kind of way. it also does not fly high enuff. help?

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Re: Building techniques

Post by genius98 » April 5th, 2011, 5:11 pm

oh yea, and my helicopter also has 2 sticks holding it strate insted of 1. keep in mind of that plz

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Re: Building techniques

Post by genius98 » April 5th, 2011, 5:15 pm

and guys, how light should it be? cuss i use a frame for the rotors and its like more than 20 g. does cutting down the weight make a difference? if so how light should it be and how would u build it?

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Re: Building techniques

Post by thewinner » April 5th, 2011, 5:41 pm

20 GRAMS?!!! :shock: How does it even get off the ground?
You should be aiming for around 4 grams. Weight makes a HUGE difference, especially when you're cutting 16 grams off. If you can cut down to around 4 grams, expect at least around a 1 minute flight.
As for building a better heli, what exactly do you mean by 'frame'?
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Re: Building techniques

Post by chia » April 5th, 2011, 6:54 pm

genius98 wrote:my helicopter only has one side rotating. so far its my best helicopter. but the problem with it is that it dosnt fly long and when it goes up it goes in like a circle kind of way. it also does not fly high enuff. help?
oh yea, and my helicopter also has 2 sticks holding it straight instead of 1. keep in mind of that plz
and guys, how light should it be? cuss i use a frame for the rotors and its like more than 20 g. does cutting down the weight make a difference? if so how light should it be and how would u build it?
A split motor stick (that's what a motor stick with two sides is generally called) is perfectly fine.
Did you mean 20 grams for the complete helicopter, or for the rotors...? Either way, that is far more than necessary and in fact is almost certainly hurting your flight time. Are you using basswood? With the right dimensions of wood (1/16 x 1/16 for rotor pieces, maybe 3/8 by 1/4 for the motor stick, less if you're using two pieces for the motor stick) balsa wood should be fine - basswood spars can be used for the rotors if you really want.
Also, what do you mean by one side rotating? One rotor is being turned by the rubber and the other is permanently attached to the motor stick? Or something else...?
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Re: Building techniques

Post by kjhsscioly » April 5th, 2011, 9:23 pm

Genius, is heli a division b event in your state? because ordinarily, it is a C event. With 20 grams, your rubber won't have the power to pull that much weight off the ground. When the weight minimum is 4 grams, you should build to as close to four grams as you can, it will help massively. Also, where is that mass coming from? with a split motorstick, you should use 1/8th square pieces for both sides, and it should be balsa. Be very cerful, because basswood is sold on the same shelf as balsa, but it can be four times as heavy. Also, be spare with glue, using superglue in minute drops, or wood glue. Covering should be as light as possible as well, because otherwise it can add a great amount of weight.

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