direct drive tail

[steve28]

help please , Im trying to get a direct drive tail motor and prop to work on my BCP . problem is its too fast . I try and trim the rudder all the way zero and the prop still turns to fast and the heli yaws slowly , I end up having to give left rudder control to slow the tail motor so it holds in one place , Im using a G190 non - heading lock .

[steve28]

ok I think travel adjust on the rudder channel has tamed this beast

[steve28]

nope travel adjust on the tail redused to minimum and the tail still yaws but more slowly now , so i guess im close but damn why isnt the gyro doing its job properly ??

[steve28]

im going to try trimming down the prop to see if that works

[steve28]

F*ck I hate this helicopter nothing but grief , tried to trim the tail finally got it close to hovering with out having to give rudder then tried a piro , and there was absolutly no power to piro , and because Im testing it my basment it piroed into a wall and smashed it all to hell , the CF main blades are ruined and my bell hiller grips are toast . :arggg: :arggg: :arggg: :arggg: :arggg:

[Danyboy]

If you would have waited for an answer...

You wouldn't have ended up with toast... ;)

Ok, serious now...

Short version:
1. Be patient.
2. Know your vehicle.

Your problems lies with the proportional...
In your electronic-block on the BCP you have a dial for proportional. What it does, is change the amount of tailrotor that is being mixed of the main-motor. You can look at it like an extended trimming function for the tail. If your tail drifts, you should tune proportional until it's fixed.
Some minor tuning has to be performed on the transmitter during flight due to falling battery voltage, but that would only be some "clicks", like about ten at the most.
If you read your manual, it will tell you more about it... Major trimming should be performed on the Electronic-unit itself.

Another advice:
To safe money (and nerves... ;) ), I *always* have my training gear handy. Whenever I think something's not asound or I fiddle with settings, it goes on...

Hope it helps next time...

Cheers,

Daniel

[steve28]

your solution assumes Im using the stock three in one controller , Im not using that .
My BCP is all separates . Im using a futaba G190 non heading lock gyro and a 5 amp dc motor controller on the tail . The G190 has only got a gain trim for getting the wag out and thats it , my radio has revo mixing but that didnt work to get it sorted out . Im mothballing my BCP for now , its just too darn expensive to repair for what it is , frankly the blades shouldnt be more than 10 bucks a pop but the reality is there triple that price so My BCP can kiss my ASS if it thinks Im going to repair it . I always wanted the direct drive tail but I guess my setup wont allow it . sucks

[Danyboy]

Well, then the solution is still quite simple:
You need a mixeron-board... :)

And then, we're back to "know your vehicle"... ;)
Which not only involves knowing the looks of it, but also it's workings and those of its components...

The 3-in-1 mixes a "base-amount" of main-rotor to the tailrotor, since in hover you need some RPM there. The Gyro and stick-input do only modulate/correct the amount of what is sent to the tail...

If you simply and directly connect the tail-ESC through the gyro to the receiver, you have 50% power output with all sticks centered. Depending on engine-power and prop, you will have a different thrust than stock, so you might need to adjust center-point of tail on the TX.

Revo-mixing only comes into play when you have a non-rotating tail in hover which starts to drift/turn when applying or removing pitch/power.

What could be a solution (if you don't have a mixeron-board), is a mixer the germans call "dynamic mixer" (sorry, coming from there, do not know some specific technical expressions you guys use over there).
Opposite to the revo (which is called "static mixer" here), it will mix the tail not off the Pitch, but off the throttle, thus eliminating the mixeron-board. Originally designed to correct for engine-bogging with combusting engines on high-pitch or pitch-change situations, you might also "mis-use" it to accomodate your situation/configuration.
With this, you can mix amount of tail based on main-rotor (as the mixeron-board does).
Once you have a steady tail with 0°-pitch, you can go on with revo to eliminate yaw-moment related to adding pitch.

If you assume it's clear for everyone that you're not using stock-parts...
I can't and won't speak for others, but I can simply not know it, if you don't write it... ;)

So, what's your complete setup?

Cheers,

Daniel

[Pinecone]

a) Without 3 in 1 or mixer, ou need to set mid stick to not rotate. Do that via sub trims.

b) With non-heaing hold gyro and no mixer, you need to set a revo mix to mix out tail movement with throttle or pitch change (pitch changes torque, which is what the tail actually counter acts. IN full scale the pedals are called anti-torque pedals).

[carlo_the_wonder_frog]

What Pinecone said, use your subtrim on the rudder channel to get it locked in. If the heli is yawing to the right, then some negative subtrim should counteract that. I find that I have to reset my subtrim every time I plug in a new battery, but it only takes 30 seconds or so to get a good lock. Once setup the tail holds very well.