Loading Your Rudder

[Garn]

Just wondering if anyone can tell me how to grind my rudder. How much, what angle, etc. I have a Moomba.

 

Thanks,

 

Garn

[rodltg2]

You will want to start at the right trailing edge . A little can go a long ways so start small. You cant go back! I did this on my MB and it helped.

[T8skier]

So if the boat is pulling hard right do you grind on the left side?

[usaski1]

I have taken at least 1/8th inch off of my Moomba's rudder (on the right side) and it has not helped. Maybe it has, just a bit. Im going to grind it more this weekend. I don't know what the deal is. Essentially I've ground quite a bit with no results. If you oops, and grind too much, you can always grind the other side.

[DW]

Some info from a few threads randomly assembled. It makes a difference on which prop rotation you have, LHR grind on right side, opposite for RHR.

[thompjs]

The Malibu LX have a thick rudder, I used to grind quite a bit on those to get any effect.

[Garn]

So start with about 1/8 inch. At a 45 degree angle?

[Garn]

@DW I read the info you gathered and the part about attaching a piece of plastice to the rudder intrigues me. Any idea where exactly would you attach it? I believe it would be attached to the left side of the rudder. But would it be attached towards the bottom, middle, or top of the rudder? Also, where do you get the plastic? What exactly is a plastic shop?

 

Thanks for your help.

 

Garn

[BraceMaker]

"What exactly is a plastic shop?" more like a plastic supplier, If you need scrap plastic I have tons. But I believe "starboard" is more of an engineered marine plastic that is supposed to machine like wood/using woodworking tools.

 

Not that other products wouldn't work for the same purpose.

 

You would of course still be drilling into your rudder, so not for those who do not drill and tap straight holes.

[Chuck_Dickey]

@garn

 

if the prop is LH rotation, grind the trailing edge on the right (drivers side). Do not make it a 45 degree, it should be more rounded lead in and out. The more you remove, the more the boat will want to turn right. Personal preference as to how much, but you want enough to keep it from wandering as you steer down the lane. Tour/Promo boats have a fair amount of pull.

 

If you grind too much, you can not always fix it by grinding the opposite edge because it will fight the other side and you are right back to the wandering.

 

Grind, drive, grind, drive, etc.

[usaski1]

Also, don't know if any one has noticed, but tracking fins are not straight on a boat... Mine are, but apparently most tourny boats have some degree of bend in them. Anyone know the specifics of this?

[DW]

@Garn: The plastic can be either Starboard or maybe ABS, etc. A marine store will have Starboard or a local plastics supplier (yellow pages) will carry something that will work. You can attach anywere along the trailing edge (opposite of grind side). I would personally grind the rudder. Check out a newer Malibu as that boat has a rudder torque tab you could simulate with the plastic piece and you will notice it is not that big.

[Garn]

Those of you who attached the plastic to your rudder, do you have any pictures of it so I can see what you did?

 

Thanks,

 

Garn

[BraceMaker]

Garn, I tuned mine by grinding, but if you want a piece of 1/4 co-polymer plastic cut to a size, with two drilled and countersunk holes, I will mail it to you for 0$.

[usaski1]

Damn, I got fed up with my rudder not turning to the right, and shaved the @#$@ out if it last night... now it works, a little too well... Im hoping to god I can now correct my mistake with shaving the left side now...

[Garn]

@BraceMaker that is incredibly nice of you. I think I'll take you up on your offer. My email address is garnski@yahoo.com. Email me and I'll email you my address. Thank you so much.

[DW]

For a rudder that is pulling a bit too much, before you grind the other side you might try simply lightly grinding the trailing edge or putting a sharper corner on the newly ground side. This will also reduce the rudder drag some.

[usaski1]

I think I fixed it by doing both hand filling the left side, and putting a sharper edge on the right side. whew! No new rudder for me! Thanks DW