J.A.E. .21 rudder length ?

[Andris Golts]

Hi all this winter im doing a steering system upgrade on the jae .21 i replaced the Futaba 3305 analog servo with a Hitec HS-5646WP digital servo swapped out the 2-56 steering pushrod for a 4-40 and replacing the TFL rudder that has some slop in the upper bushing with a Speed master mini rudder assembly SPDR-005-H which brings me to my ? . The length of the Speed master is 4'' a 1/4'' longer than the TFL . Doe's this matter ? What rudder length do most of these riggers run ? I also noticed the water pickup slot is 3/4'' higher on the Speed master. Would this make a difference for water cooling? Regards Andris Golts.

[jim82]

You can always cut the rudder down and as long as the water pickup is in the water it will do its job.

[rol243]

Its not bad to have abit more rudder blade in the water on the riggers as it does help in holding the rear from sliding in fast turns. my rudders are approx 1.5 inches lower than the rear of Ski on the JAE,s but 2 inches could possibly be better. keep your rudder throws low to a maximum of 1/4 inch left and right.

[Andris Golts]

Thanks for the replys. Regards Andris Golts.

[Rookieboater]

Your rudder length should be based on the depth of the prop when one of the blades is completely in the down position. If you base it on where water pick up or ski is then the depth could be too short/ I would go 1-1/2'' below bottom of prop as a minimum.
JMHO