Rudder set-up Question

[kacordy]

I'm trying to dial in my new PT P-spec, 2030 etc. For the boat to run straight on its own down the strait, I have to adjust the rudder a little left. Is the turn fin pulling the boat right? So it needs left rudder? Or do I need the put a few degrees of left or right angle into the strut. I would assume for optimal performance, less drag, the rudder should be completely straight down the straits, less drag.

What is the correct Theory?

As always I appreciate the help, Allen

[ray schrauwen]

Rudder needs to be straight. Turn fin needs to be parallel to the boat center line or it could be pulling to the right. You can shim it causes the boat to go straight or build a piece of aluminum inside to tie the turn fin to with a bolt & nut system to make fine adjustments.

Nice paint.

[flraptor07]

That thing sure is purdy! Ray is dead on, turn fin needs to be adjusted so it runs strait with the rudder neutral.

[kevinpratt823]

I find the same thing with my Whiplash(built by Ray ), and figure it's primarily due to prop walk, especially with higher pitched lifter props. To me it seems that with the rudder offset to the left compensating for the drag of the turn fin on the right, something will need to be trimmed at least a little to compensate for prop walk to go straight. I also have always trimmed the rudder, looks like I have some turn fin shimming to experiment with this season.

[ray schrauwen]

I want it back

Biggest mistake of my life!

I find the same thing with my Whiplash(built by Ray ;) ), and figure it's primarily due to prop walk, especially with higher pitched lifter props. To me it seems that with the rudder offset to the left compensating for the drag of the turn fin on the right, something will need to be trimmed at least a little to compensate for prop walk to go straight. I also have always trimmed the rudder, looks like I have some turn fin shimming to experiment with this season.

[ray schrauwen]

I have to build an ML335 before June 22... fun WOW!

[Flyguy55]

A prop that is not razor sharp will also cause prop walk to the right .

[ray schrauwen]

Thinning a prop also cuts down on walk.