We have a Moody 376, which has a bolt-on cast iron keel. The boat’s
hull had been coppercoated many years ago and the keel was regular anitfouled.
We decided to bite the bullet and get the whole thing redone with coppercoat in an attempt to avoid having to
haul out each year. We figured if the coppercoat lasts 4-5 years then the extra expense upfront will have been cancelled out and every year after that is a bonus.
The main concern, having read what I could on the
internet, was the preparation of the cast iron keel. The require for it to be treated properly to avoid rust is crucial. We got a number of quotations from various yards in
Greece (where we are). Based on a number of cruising friends giving very positive feedback about a particular yard, we decided to go with them.
They did the following:
- Sanded back the
hull
- Sand blasted the keel all the way back
- Used
epoxy filler to fill the expected unevenness of the keel
- Applied 4 coats of epoxy primer to the keel
- Applied 4 coats of coppercoat over the hull and keel
They did the
work over the course of 5 weeks. They let the
boat dry out for about two weeks before starting
work on it. They were supposedly watching the humidity and picking the best time to do the work. They sent progress photos as they went.
We returned to the
boat just before they applied the coppercoat, so I had a chance to see the primed keel and to me it looked really good - smooth finish (but I’m not expert of course!)
Anyway, we launched and here we are two weeks later and there appears to be a problem. On the port side of the keel there are 12 rust spots that have appeared - like pin holes where rust is “oozing” out. On the starboard side there is on pin hole spot, and one section where a rust line is appearing along the hull-keel join.
Having reread other people’s experiences with coppercoating a cast iron keel, it seems this is not good, especially after only two weeks of being in the
water. The flip side is people always say “cast iron keels are impossible to keep rust free to so things like this are inevitable”.
We don’t have an opportunity to go back to the yard that did the work, so that is not an option.
I’m trying to figure out:
1. Is this normal, or considered an acceptable outcome after two weeks in the
water?
2. Is it something that needs to be fixed (ie: I can live with the rust spots, but I can’t live with the coppercoat itself becoming damaged and flaking off)?
Thanks