Cavitation burns on Fiberglass rudder

[backman]

I saw my bottom for the 1st time yesterday and found this. (I had a heads up already the rudder was fiberglass so it wasn't a total surprise but..

now what? Patch it up; send the prop out for balancing and on with my life?

Do I have to worry about a structural failure?

And for extra credit - why fiberglass?

 

[Blitzen]

Talk with Eric S. and have a stainless rudder made, you will improve water flow and gain speed.

 

[MDI45]

Backman,i had a glass rudder on my Wayne Beal and never had a problem...they were made in house i guess to save a few bucks...The only thing i worried about (which happen to a few guys i knew) was the pins would snap that held the glass rudder and shaft in line...but if constructed well i think there is nothing wrong with it.....i would just repair it....it alot less work then removing the whole thing

 

[captainlarry84]

Without knowing your boat I would guess that you have high HP and a large propeller. Fiberglass rudder are fine @ 15 knots with small wheels and reduction gearing. However when you up the ponies the glass rudders take a beating. We did a repower on a 35 Bruno from a 210 CAT to a 440 Yanmar. Needless to say the rudder did not last a season after the repower and it was replaced with a bronze rudder.
I concur in having on made in metal. They are thinner to allow water to escape easier and they can really take a beating against the high speed water flow. I like the way that Ken Flowers has designed his rudders you may want to inquire. Lastly I prefer Bronze over S/S however the cost of bronze is very high.
Removing the rudder is a pain. You will need to block the boat pretty high to swing it out. Plus the stuffing box has to be removed to give the rudder post play to swing out. Breaking the stuffing boxes loose from the hull is not easy.

 

[backman]

Yes. Cummins QSM 670 and a 26 X 26 wheel.

Pete Lowell who invented that down east prop aerator is a dock ate. I'll give him a look this winter and see what he says. savetsky picked up the trick from him and I really don't want to drill 2 holes in my hull!

 

[Blitzen]

Yes. Cummins QSM 670 and a 26 X 26 wheel.

Pete Lowell who invented that down east prop aerator is a dock ate. I'll give him a look this winter and see what he says. savetsky picked up the trick from him and I really don't want to drill 2 holes in my hull!

No need to put that aerator in, talk with Eric and put in a stainlless rudder.

 

[monktails]

Larry have the prop checked it looks like there is cavitation burn there also.