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[derekwarner]

Wallace.....simple L shaped wire connections joints like this & in this scale when multiplied x 4 in the dual linkage can provide say 3 mm slop of rudder movement

The resultant also causes electronic Rx dither attempting to catch up with the floating rudder

Please consider..........  say $10.00 US for a set of four DU-BRO ball & socket linkages ....available from all model supply stores..............Derek

[malcolmfrary]

The dual linkage does not quadruple the slop, as each linkage just sticks with its own.  If there was a link from servo to a lever, then a link from lever to tiller arm, yes, four lots of clearance to take up.  If the clearance is small in the first place, then four times very little is still not much.
Does a bit of slop in the linkage induce electronic Rx dither?  No way.  The TX generates a signal that the RX resolves to information for the benefit of the servo.  The servo takes up a position corresponding to that, and stays there.  If the rudder flaps about a bit, (nothing like the 3mm mentioned) it only puts a bit of loading on the servo gear train and does not reposition the servo which would cause it to try to drive back to the required position.  Generally, the linkage is outside of the control feedback loop.
In a high performance boat, a lack of play is probably an advantage by maximising precision, in a scale boat with much lower performance, it reality, it doesn't make a blind bit of difference.
Here in the UK, DU-BRO are all but unheard of, however, paper clips are a reasonable fit in the holes and readily available, about £1 for a few hundred.

[wallace]

HI TO ONE AND ALL  THIS IS A MESSAGE TO YOU ALL HOW PUT A REPLY TO MY QUESTION ABOUT THE RUDDER TO THE SERVO I WAS MADE UP WITH THE REPLIES I GOT MANY MANY THANKS TO YOU ALL.YOU ALL DESERVE A MEDAL.
I WOULD LIKE TO SAY THAT TODAY I HAVE FIXED THE QUESTION I ASKED.
I HAVE PUT Z BENDS IN BOTH ENDS OF THE WIRE FROM THE RUDDER ARM TO THE SERVO AND HAVE TESTED IT A FEW TIMES DONE IT AGAIN A FEW HOURS LATER AND I MUST SAY ITS ALL WORKING GREAT AND ITS NOT LOOSE OR POPPING OUT.MANY MANY THANKS TO YOU ALL.

[John W E]

hi there all

I always followed the practice of never putting metal to metal on steering gear /steering linkages whereupon the push rod goes through a metal tiller arm.

or...a metal servo arm.

Because I was led to believe that this could cause 'glitching' in the radio equipment - so - I have always avoided this practice, by using a plastic joining clip.

The above procedure I follow stems from the days of the notorious 27 mghz where they were very prone to outside interference, but, as I say, I still carry it on - even though I use 40 mghz now.   Just a passing thought that is all, if you ever have any problems with 'glitching' as in electrical glitching on your radio gear.  This may be the source of problems.

aye
john e
bluebird

[wallace]

Thanks John will remember what you say.  wallace

[derekwarner]

Wallace ....malcomefrary is totally correct ..in that

1) it is not a four fold error ....but a two fold error

2) my comment of a 3 mm slop was meant as a radial degree [arc ...dimension] as measured at the extremity of the rudder blade [this gramitical glitch is due to being humble convict stock from the first fleet to OZ in 1778]

You will see that 'bluebird' has offered experienced comments as    & relative to my  to my previous posting.......Derek

[FrankM]

So I'm a few months late - just happened across this thread so for anyone interested.................

Being a model yacht person, I use a lot of discarded carbon fibre fishing rod for masts, booms etc.  This tends to leave me with a lot of "little / skinny" bits in the spares box. 

So the BEST connection I have found between servo arm and anything (rudder arm or ............) is a piece of carbon fibre rod with a hole just about right for a 2/56 thread that takes a normal snap fit clevis.  Simply epoxy the thread into the carbon fibre rod for about 2cm at each end leaving about 2cm exposed.  That gives adjustment at either end on a rigid, stong and lightweight connection.  Clearly, you have to take a reasonably exact measurement of overall length of your connection and cater for the length of threaded rod you will use but you have the adjustment - just don't be TOO LONG to start with. 

Hope this is useful to someone.

Frank