Mhz Mystic S turning problem

[ED66677]

that can only be too much play in the rudder linkage or servo horn! it's not brutal it's smooth in both direction!

[RaceMechaniX]

If the turning problem is happening at such very low speeds I have some new guesses:

1. It appears the motors are turning at different speeds to cause such a drastic direction change at low speed. Are you certain the ESC's have the same throttle curve? Are they connected with a Y connector or are you using a third channel mix in the radio? If using the third channel mix in the radio I would bet it's incorrect. I also assume you are not trying to use bias throttle control to steer the boat.

2. At low speeds you can hear the props cavitating a lot. It may just be that one is hooking up a little more than the other casuing the turn.

3. have you tried any other props to see if the problem gets worse or better?

Tyler

[bjornar]

that can only be too much play in the rudder linkage or servo horn! it's not brutal it's smooth in both direction!

I have tried to go faster, then the turning is brutal. I cant understand its in the linkage or servo horn. I have tried to turn the rudder by hand, and its not possible. At this low speed I cant see how its possible its the rudder. And its turning when I drive straight when its no load on the rudder...

[bjornar]

If the turning problem is happening at such very low speeds I have some new guesses:

1. It appears the motors are turning at different speeds to cause such a drastic direction change at low speed. Are you certain the ESC's have the same throttle curve? Are they connected with a Y connector or are you using a third channel mix in the radio? If using the third channel mix in the radio I would bet it's incorrect. I also assume you are not trying to use bias throttle control to steer the boat.

2. At low speeds you can hear the props cavitating a lot. It may just be that one is hooking up a little more than the other casuing the turn.

3. have you tried any other props to see if the problem gets worse or better?

Tyler

1. I have tried different esc`s and reset them some times. So the throtle curve should be the same. They are connected with Y connector. What is Bias Throtle?

2. I was thinking of this, but it happens from straight driving and to both directions.

3. I have just tried the Graupner K 40mm props. I have a couple of 35mm 4 blade I can try tomorrow...Its starting to get late here in Norway.

Bjørnar

[BakedMopar]

If you are certain that there is no slop (even a few degrees) in you rudder then we need to look at other possibilities. You could try to connect your power wires from both esc together so both escs see the same amount of power. This is how I run my twin cat. That's the only thing I can think of. Try it if it don't work then I'm just as stumped as you!

[RaceMechaniX]

Bias throttle- would be if you decrease on esc in a turn to let the outer most motor run faster to help it steer. Think of a tank or caterpillar tractor. This is not the case if you are using a Y connection to both esc's.

I agree that linking the two batteries together is a good idea, but it looks like you have a very tidy set-up with good equipment so I guess there will be little difference, but its worth a try.

TG

[xkos]

I have the 44 inch mystic and after a couple of tests i realized that the hull turns better when you are moving fast...

[bjornar]

Bias throttle- would be if you decrease on esc in a turn to let the outer most motor run faster to help it steer. Think of a tank or caterpillar tractor. This is not the case if you are using a Y connection to both esc's.

I agree that linking the two batteries together is a good idea, but it looks like you have a very tidy set-up with good equipment so I guess there will be little difference, but its worth a try.

TG

Then I will make the link between batteries and try different props.

[bjornar]

I have the 44 inch mystic and after a couple of tests i realized that the hull turns better when you are moving fast...

Ok, but it should not turn like this when I drive slow straight forward.

[bjornar]

Now I just tried new props and adjusted the hight of the props. Not better. Tomorrow I will try to get the batteries hocked together.

[bjornar]

Hi again,

Then I have tried to hook the batteries together and another set of props and its still the same problem. I am thinkin...can the weight make problems in this hull? It weights 3,5kg (almost 8 ponds).

Bjørnar

[ED66677]

where's the COG?

[bjornar]

where's the COG?

CG is at 28%

[ED66677]

did you get a chance to test swapping L/R prop and flex?

[bjornar]

did you get a chance to test swapping L/R prop and flex?

No, that one I forgot. I will try, thanks.