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Pumpkin drop event

building a new Hobby King 550 flybarless

... still taking deeper breaths and switching between 500 and 550. Basically I keep on telling myself: what the hell :) so it will be a 550 probably.
For the gyro, could you let me know if, in principle, the kds flymentor can be used as a standard fbl gyro? I am keen to buy it because I imagine that I can choose whether to have a stabilisation systemor just the slightest gyro contribution possible.
Any ideas, comments on this? Thanks!

Ak Flyer

Fly the wings off
From my quick read it looks like you can use the gyro alone or activate the camera and use the stabilization system. That's not a bad deal. Still more expensive than some. I haven't heard anything about this unit so I'd be more inclined to use something with a reputation. What have you heard?
I read a couple of resentments but it was more about: i dont know how to fix the swash mix. That kind of users basically. While I do have lots of affinities with complex electronics.
Otherwise it would be the ZYX, but the cost is similar. At least kds is not the absolute junk of brands, so right now I would be keen to try it, especially since i have a full windows interface to fiddle with.
As long as it can be used as a standard, fbl gyro system, then I am happy.
And please excuse me if i keep on touching all kind of topics at random. It s just that I dont want to "buy and learn". I am taking advantage of forums so to "ask and learn", and then buy the right stuff only...

Ak Flyer

Fly the wings off
No problem. Personally, I really like the Skookum 540. If I manage to build the G30 V2 that I'm wanting, I'm most likely going to use the 540. I have heard really good things about the BeastX system as well. My heli guru at the hobby shop says that he's tried a bunch of different ones and prefers the BeastX.
I like your support! By the way, whereas servos (evidently) and also esc are to be chosen for the correct size, there is no such issue for a gyroscopic system, right? A gyro is a gyro is a gyro I guess... or? From a 250 to a 550 could I use the same unit?

Ak Flyer

Fly the wings off
I like to help. I've enjoyed the questions.

For gyros, that's pretty much the case. I have a Futaba GY520 gyro on my 400 and it says right on the box that you can install in in anything from a 250 to a 700. I'm sure you could also use it on 800's and bigger gassers or tubines as well. Since all it does is detect rotation and signal your tail servo it really doesn't matter how big it is. From what I've read, the Skookum, BeastX, Align, Futaba etc all tell you that you can use them on any size heli. The only thing I can think of that may limit you is high amp draw stuff. I'm talking high torque digital servos, may cause the cheaper units to get hot. That's only a guess, but something I would look into before building an expensive heli. For a 550 size I think you should be fine with anything.


Junior Member
Why do all these people need over 2200 head speeds on helicopters these days, nitro's fly fine enough and the 30-50 size's only get to 2200ish head speed at most.

Electric helicopters have 2 main schools of thought, you are either building them to run the motor at 100% throttle the entire time (Making sure the motor won't overspeed the blades at full throttle.) or you are building them to be run at around 80% throttle with a 20% motor torque left increase on hard maneuvers. From the limited FC3 experience I have flown and seen in you want a consistently lowish RPM that never deviates, high RPM's cause twitchy and unpredictable behavior in maneuvers and the increased gyroscopic effect can make the helicopter seem 'stiff' in the sky. Its much easier to smoothen out a lot of maneuvers at a lower head speed.

::EDIT:: BUT NOT TOO LOW, if you go down too far they tend to wobble out of hard stops, its a balancing act.

And yeh, I still don't understand this 'high headspeed' thing for electrics. They get incredibly twitchy which makes them fun to throw around in 3D but otherwise makes them difficult to control, as a rule of thumb most 30 size and higher helicopters will fly quite well on 2000-2200 rpm for beginners. Although I did put 2400 onto the X50n Flybarless a few weeks ago with a pinion change and lets just say its a scary powerful nitro, I don't need that much blade power with where I am at.