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[bigfella]

Hi All

I have a problem which the answer is probably staring me in the face, but here goes.

I have a problem with space inside my boat, so much so that a servo wont fit standing up as it should so I have to lay it on its side. This servo is for the rudder and makes the servo perpendicular to the rudder arm.

I have those Universal ball couplings for both rudder and servo horns. My question is, both the rudder horn and the servo horns have various positions for placement of the couplings, either close to the center or the ends, Which is better for maximum performance?? Both at ends, one at end one at center..etc there are so many different combinations and the fact that the servo and rudder are on different plains. I know the answer is probably a simple one but hay I am simple

Regards David

[Circlip]

What "performance" are you after bigfella? max TORQUE or THROW?
 Servo first, holes nearer centre give max torque but reduced throw.
 Rudder arm, holes nearer centre give more throw.
 If you connect outer holes on servo to inner holes on rudder you could get into a mechanical lock up, and inner holes on servo to outer holes on rudder, not enough movement of rudder. So max power from inner holes on servo. Set ALL electronic gizmo's on transmitter to NEUTRAL before setting linkage up.

[bigfella]

This is the sort of thing I do not know. I would like the max amount of steering available. How ever I can assume that if you played it safe and used somewhere in the middle of the two options. This sort of thing is all new to me.

Regards David

[MikeK]

It is a case of 'suck it and see', but I have found with yachts that it almost always ends up with outside holes on servo to inner on rudder, but depending on the type of of horn on the rudder, care is necessary to avoid lock up as Circlip advises

Mike

[bigfella]

Is there any problem in regards to the servo being on its side and the rudder horn and servo horn being at 90degrees to each other.

[Circlip]

No problem as long as the servo is not stalled due to lack of free end movement, before the EASY ball joints you could see some real wire "sculptures" to connect the bits together, but you just had to be carefull not to jam them.

[tigertiger]

Is there any problem in regards to the servo being on its side and the rudder horn and servo horn being at 90degrees to each other.

Think about using ball joints. Perhaps on both ends. Rather than a 'z' bend in the end of the rod at the servo end.

You beat me to it Circlip
 

[Circlip]

He is Tiger, but the position of the ball joints still need to be level/square to the arms they are fastened too to get free movement.
 To try to clarify verbally, in side elevation the holes in the arms are going to be at right Angles to each other but in plan view you should try to have the vertical line of the servo arm in line with the centre hole on the rudder arm.
 Double mod Tiger Bigfella before you ask, NO snakes, too much backlash.

[malcolmfrary]

As long as the servo is exerting a straight push and pull, it doesnt matter whether it stands up or lies down.  The rudder doesnt usually do anything extra going beyond 45deg either side, which is convenient as that is what is usual for a servo.  I have never liked increasing the rudder throw by "gearing up" due to the latch up problem mentioned before, and usually go for the outermost holes.  This is because my linkages consist of wire which is a loose fit in the holes, so that slop becomes a smaller percentage of travel.

[Telstar]

Hi

I have a problem with space inside my boat, so much so that a servo wont fit standing up as it should so I have to lay it on its side.

A slightly different approach  Have you looked at a low profile servo (like the Hi Tech HS 77) these have the same 'footprint as a normal servo but only about half the hight.  (23 x 44 x 25 mm).    I use one as a sail winch in a small sailing boat where I only have 45 mm between hull and deck, perversely the rudder servo is a standard servo on its side, with ball ends on the linkage , I had to suck it and see before I got the rudder throw I needed (something like 30^o either side
Happy New Year
Tom