In the summer of 2015, while departing for the Netherlands, I hit the concrete footing outside Fort Blockhouse in the entrance to Portsmouth Harbour. There’s no excuse for it — I was cutting a corner inside the channel marker, confusing it with the next one out.
This Google Maps image shows the footing quite clearly, but not the channel marker. In reality, this concrete is hidden under water, but you can see how nasty it is.
Here’s a photo I took much later at a very low tide.
It was a big knock for Tammy, but I didn’t get to see the damage until I hauled her out in early 2016.
Oh dear. That’s the forward edge of the starbard keel, about half-way down.
And that’s a bit further up on the inside.
I ground away the damaged fibreglass. The hole went right through the skin, revealing a black wet fibrous substance behind. I’m still not exactly sure what it is, but I suspect it is some kind of resin encapsulating the keel ballast.
The material stayed wet, so I decided to investigate by digging a small hole into it.
The hole wept a black fluid, which kept flowing for two days, gradually slowing down. Once it stopped flowing, I stuffed tissue paper into the hole to encourage the moisture to wick out of the material, and eventually it dried up.
What was left was slightly fibrous and crystalline.
I decided not to worry about it any further at the moment. The next time Tammy is ashore for the winter, I may drill holes into the bottoms of the keels to drain them and then re-seal them in the spring, possibly with some kind of shoes attached. The undersides of the keels are looking worn, as you can see in this picture taken while she was on a crane later that year.
Here are both the holes, cleaned up and dry. Some of the fibreglass along the forward seam was looking a bit dodgy, so I decide to patch that as well while I was working. You can see where I’ve cut a groove between the holes.
With that done, I started to lay up glass to repair the hull. As I’ve seen recommended in several videos, I laid down a large patch first, then added smaller patches until I’d built up a repair.
I then ground away the excess to restore the keel shape.
With hindsight I could’ve added another layer of glass.
Finally, I applied clear gelcoat, then sanded the result smooth. I somehow forgot to take a picture of the smooth result!
You might wonder why I chose to use clear gelcoat. Well, these repairs are below the waterline, and will be covered by antifouling, and I didn’t see any cosmetic reason to hide them. I’d rather be able to see clearly where my repairs are and perhaps see into the top layers of layup for problems. I also have no motivation to hide my mistakes and repairs, as you can tell by this blog!
This year I dried out Tammy at Portchester Sailing Club, to inspect and clean her bottom, and that gave me a chance to look at my repairs.
There’s no sign of any problems, and I’m happy that Tammy is seaworthy. I plan to make a more thorough investigation of both keels when she comes out this winter. In particular, I think I’ll make some small inspection holes from inside the boat and send in my dad’s endoscope to see what’s there. I’ve read articles from Corribee owners saying there are quite large voids above the ballast, and even one suggesting they might be a good place for water tanks.
If you have any suggestions for improvement, or ideas about what’s inside my keels, I would be very interested to hear.