Strange appendage

If youre doing bottom work get rid of that silly deflector. They can injure a diver and dont really work well. Best to center the rudder, completely bog fill the rudder skeg gap then epoxy the rudder to skeg. Once cured take a hack saw blade and precisely cut thru the bog to release the rudder from skeg. Work the rudder back and forth to test if your cut was perpendicular...if not fine tune. You will now have a zero tolerance gap...no rope will jam. I havent used a deflector in years. My rudder skeg tolerance is close enough to wear the antifouling .

Also add a set of flaps..port starboard..to fair in the rudder to skeg.

Kelp cutter http://www.wdschock.com/boats/schock40/kelp_b.php

 

If it was my boat I would consider doing those things.

 

Oh...

 

Leave it alone.

"If it ain't broke, don't fix it."

-Tom

 

I agree that it is a line cutter, but I offer an alternate. It might be creating a small vortex or water flow disruption which allows some stress release at the rudder root.

Similar to this:
http://forums.pelicanparts.com/pors...6276-question-aero-experts-2.html#post1782976

 

I agree, it's likely a line cutter BUT, usually these are reverse raked with the sharp cutting edge near the base.

-Tom

 

I think this is most likely a deflector more than a cutter to stop weed getting between the skeg and the rudder.

 

Agreed.

-Tom

 

maybe an old type speed log, works on pressure or vacuum