Rudder damage discovered after bottom paint removal to gelcoat

[Verano]

Recently purchased 2000 34mk2, decided as part of our total rigging refit to strip back 22 years of bottom paint and sleep better at night knowing what the previous 2 owners had done or not to the boat. We discovered grounding damage to the keel and rudder(could be 2 years old, or 18), both repaired at the impact sites. We discovered on the rudder there is a hairline crack from the post down about 10 inches on the leading edge, I am assuming this damage is from the impact and has resulted in water penetration, but to what extent we do not know. I understand there can be other ways for the crack to have formed and for water to have entered as well.

In any event, before getting everything barrier coated I'd like to make sure I do a proper repair, the yard suggested to die grind it back and lay up some new glass then barrier over top. Any thoughts? I put my moisture meter all over the rudder and found no elevated readings, and no water came leaking out when they walnut blasted the bottom indoors over the winter and exposed the crack. I don't know if this crack has been stable for 10 years, or if it happened last year if that makes any difference.

Photos attached. Thanks in advance for any knowledge!

 

[sail sfbay]

My reo cents...yard has the right approach.

 

[dmax]

Interesting crack, not sure if an impact would cause that as the forces are exerted on the leading tip at the bottom and aft of the post at the top. As the yard says, I would grind it out and inspect the depth of the crack and look for evidence of water intrusion. Most likely you could just patch it up and be good to go. A 2000 Catalina will have a Stainless Steel "flag" inside the rudder (prior to about 1990 they were steel) so you shouldn't have any internal problems as long as the glass hasn't delaminated (doesn't look like it). I would also drill a couple of 3/8" holes in the bottom of the rudder and see if any water drains out - if it does, let it dry out for as long as possible. It doesn't look bad and the rudder looks like it's in good shape overall. I would take the opportunity to bevel the glass out where the rudder post enters the rudder and fill it with 5200 to ensure that no water enters there. Also, make sure the top of the rudder post is sealed (can use foam) so that rainwater doesn't come in through the post.

 

[RitSim]

I had a C30 and did this repair as well as some "bubbles" (3" x 8") under the skin. I had cracks, as you did, on the leading, trailing edge as well as the top flat and bottom. I did my repair at home over the winter so I was on saw horses. After the normal sanding and prep I used 6" fiberglass tape topped with 3" tape. I chose the tape so I didn't have to deal with cut glass cloth edges. A key part to my repair was to wrap the resin saturated cloth with saran wrap. The wrap allows you to smooth out any resin accumulations. Be sure to make the saran wrap COMPLETELY smooth with no overwraps or wrinkles. When cured, the saran wrap comes easily off leaving a smooth even surface. You may have to add some additional 2nd coat resin to the tape edges- use the same saran routine, Sand and fair as reuired, barrier coat and bottom paint. Good Luck

 

[Tally Ho]

I had some cracks on the leading and trailing edge of my rudder (O’Day 322 ). I sanded both edges down, then glassed over the leading and trailing edges to seal them. My cracks did not extend so far up the rudder though.

My boat is back in the water (2nd year), and no issues so far.

Good luck with yours.

Greg

 

[Verano]

Thanks all for the input, watched a few Youtube vids about rudder construction etc, along with the helpful suggestions I think I have a good course of action. Will start with some drain holes and see if anything comes out, if not, will grind, patch, barrier and splash.