Rotors

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kjhsscioly
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Re: Rotors

Post by kjhsscioly »

illusionist wrote:Do hobby stores give you discount if you buy in bulk? :D Cause I would love that. Last time I went they had the crapiest balsa... Maybe I should learn to cut my own 1/16 x 1/16
It is actually really easy. C-clamp a metal ruler to the table, over a sheet of balsa. you can measure or eyeball the distances, and cut with a sharp blade.
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Re: Rotors

Post by illusionist »

Okay, I just tried it out with 1/32 sheet balsa, and it worked quite well! Tomorrow I'm going to go out and get a sheet of 1/16 and I'll try it out. I don't have a ruler long enough, but I'll find something else.
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Re: Rotors

Post by wlsguy »

I would buy a "master airscrew balsa stripper". It is the cheapest balsa astripper available but works pretty good. Many hobby stores have them.
Because it's plastic, it will eventually become loose but at $5.69 from Amazon, just buy another one.

You can then take your scale with you to the hobby shop and weigh each sheet of wood before you buy.
It's much cheaper than buying sticks individually.

I know this should probably be in the "Building Techniques" forum but, since people were already discussing balsa stripping, I thought it would be ok
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Re: Rotors

Post by illusionist »

That one actually seems extremely easy to use. I'll ask my coach if we can purchase one for the team.
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Re: Rotors

Post by illusionist »

Well, I've gone from having a 1.26 gram fixed rotor, down to building my latest rotor: 0.56 grams! :D (Both of them with covering).
So the helicopter ends up at around 3.5 grams. Should I use some of the weight to use stronger spars for the rotors? I haven't yet done a test flight, so I am unsure of the performance.
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Re: Rotors

Post by chia »

NIce! That final weight is what I was aiming for, but it ended up around 4.04 because of the motor stick >.>
How would you go about making the spars stronger once you've built the rotors? Just glue, or reinforcement wood, or what?
Either way, unless they're made of really weak wood, your rotors should stand up fine against anything and probably won't warp much in flight. I would use some of that extra weight for ballast at the bottom. Balance the whole helicopter on your finger on the motor stick... is the center of gravity halfway up or more? Even if it isn't, ballast at the bottom can't hurt.
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Re: Rotors

Post by illusionist »

Thanks! I found one motor stick that is perfect, and I can't find another one like it (I hope it doesn't break).
I meant to make them stronger the next time by using denser wood for the spars. Right now, they bend somewhat when I blow on the blades, so I'm worried about warp during flight...
As for ballast, I will definitely put it as close to the bottom as possible.
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Re: Rotors

Post by lllazar »

My motor stick is insanely strong and it weighs like 1.8 g. But my rotors are light enough that copter is like 3.75g without clay.

Btw do u guys attach the clay before flight and then remove it afterwards? Clay loses mass due to the water evaporating to form equilibrium with the atmosphere.
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Re: Rotors

Post by kjhsscioly »

We have this clay that came with my Wright stuff kit last year. It is some special stuff that doesn't lose any mass over time, and stays wet indefinitely.
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Re: Rotors

Post by thewinner »

Yeah, I have some of that stuff too. But I'm not sure where you get more of it.
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