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Heli #4 (update)

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All I can say is this thing looks sick and very very very confusing to build, looking foward to seeing a video of you flying it Ralph, or is this just another one for the shelf, LOL!!!!
 
Let me guess, you're going to use Easy Off to strip the black ano off so you can polish the aluminum, right?

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:hehe: Sorry, no, even though I have Easy Off in stock. I already have a bling polished rotor on another heli, but this one is black for the scaler. I even ordered black blades instead of the white stock blades.
This isn't bling, this is the THING!
 
Yep dosnt look like they took the design from the Align T-rex 450 at all lol
 
You nailed it. It's a Trex clone.
All the pre-flight checks and low hovers have gone well. It's almost dialed in.

Canopy got another paint job, with twin stripes and some aluminum.
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CX 450 and her little sister, the Belt CP 400.

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weezracin said:
I always wanted to know what happens when the bat dies or they run out of fuel?

Autorotation. Same as a full sized heli. After learning to hover, that's the second thing you learn. The electrics are programmed for an RPM that will allow a soft decent at the low voltage cutoff point, but if something should go wrong, both the electrics and the nitros are put into full negative collective as they fall. That means the rotor is spun like a fan by the air it's falling through, and about 10 feet from the ground you put in positive collective, enough for a controlled landing. You only have one chance since your RPM will run out quickly.
 
Ralph,

What can a 7-channel radio do that a 6-channel won't when it comes to a 3-D chopper? What do you need in a heli radio in order to take advantage of a 3d heli? What exactly makes a 3d heli "3d"? Sorry, for all the questions but I want to learn more about 3-D heli flight.

I bought a CX2 a couple years ago and did pretty well with it rather quickly I feel. I'd like to get into a 3D heli maybe next year but I have no idea what to look for. If I did go ahead and get back into heli's I'd like to build a nice kit with all the tough alloy parts like your and add my own radio. I'd like to get a Futaba FAAST system since I'm partial to Futaba products to begin with.
 
Well, for starters, here's what I've been working on:

The Agusta Westland A-109 fuselage arrived as well as the 4 blade flybarless rotor and fiber blades.

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fs6.webp


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Windows are now in, and since it didn't come with any side windows I got blue tinted acrylic instead of clear.
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Landing gear is in, and I'm waiting on more wheels. I have the aluminum hub on the nose gear, but had to order more for the rear so I could replace those cheezy plastic hubs and foam wheels with scale duals.
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The nose wheel is now operational and I'm still working out the hardware for the rears. The gear retracts.

On a 7 channel radio intended for planes or helis, one channel is intended for retracts or flaps. In a heli, if you want to control the gyro gain from the radio, there's a channel for that. Since this is a scale project, and won't be intended for 3-D flight due to it's weight, I'll set the gyro with it's manual adjustments and have another free channel to either run the rear gear with that switch, or use it for lights.

Now, the difference between a standard heli and 3-D is in the rotor AND radio. The small helis and the cheaper ones use a fixed pitch blade that's pretty much just a fan. A 3-D heli has a fully operational rotor just like a full sized one. That means each blade adjusts to positive OR negative collective as well as cyclic pitch.
That allows you to flip the heli inverted and fly it or skim the ground with it while it's upside down, since the rotor blades are now moving air in the opposite direction. That's also what allows it to auto rotate and land in an engine out condition.
The radio allows for 3 different flight modes of 'throttle up' as well as dual rate controls. These are all set according to how extreme you want to get, as well as settings for gentle or scale characteristics.
 
I can only assume that going from a 2-blade rotor to a 4-blade rotor simply allows the heli to move more air and therefore be more maneuverable?
 
In this case, I think its more of a bling factor. Adding blades won't really do much for manueveralbility, it will help in creating more lift. (providing you have enough power to swing the blades)
 
Maybe for his heli yes, but what about an all out performance oriented 3D heli? Do people run 4-blade rotors? I'd imagine you could change direction in a hearbeat if you can move twice as much air, provided like you said, that you have plenty of power to move them.
 
I have never seen a 4 bladed heli in competition, only 2 blades. Although I will admit that I am not very knowledgeable in this sport. Tracking and balancing a 4 bladed set up sounds like more of a pain than the gains that could be made with one.
 
High performance 3-D helis rely on the flybar and paddles for super quick response time. A 4 blade rotor is for scale since there is no flybar, and the rotational mass of a 4 blade slows down the action. There's also more movement in the blades of a 4 blade head since there's no flybar to advance the motion of the heli. The flybar provides MOST of the action while the blades provide the lift, while a 4 blade has to do it all. 4 blade or 5 blade heads without a flybar are also more unstable since the flybar also acts as a gyro of sorts, similar to the weighted arms on a Huey.
Depending on the stability I get when it's all together will determine if I need to add another electronic unit as a stabilizer. They go for over $200, but act as a "Fly by wire" setup, the same as in the performance military helis and jets.
 
Thanks, MGT. The best, or worst is yet to come. I have to tear down the heli and start fitting it into the fuselage once all the retracts are set up. There are no directions with it, other than that it will fit most 450 sized helis. I'm on my own with making spacers and mounts for everything, but so far I'm really pleased with how it's turning out.
I only wish it had been raw fiberglass instead of a pre-paint, because I've found flaws that irritate me. Well, eventually it will get torn down and rebuilt, and I'll do a custom paint job at the same time.
I installed a 40 amp ESC instead of a 30 just in case I have to go with a larger motor. I have a feeling I'll be needing a few upgrades once it's ready for testing.
 
Reacting immediately to the stick input before the larger blades can react. The flybar and it's paddles can move VERY quickly and to greater extremes making the heli far more maneuverable than one without a flybar.
 
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