While working on the V-berth joinery, I’ve been getting up close and personal with the porthole openings there. And the more I saw, the more I didn’t like.
It turns out that when the guys sandblasted the exterior, they didn’t do a stellar job on the porthole openings. The fairing crew did a reasonable clean-up on the flat surfaces of the aft porthole openings, and I’d cleaned up all of the aft stateroom porthole edges and primed them with AwlGrip Max Cor CF before painting. But we all screwed the pooch on the ones in the V-berth, and it was starting to show.
Ancient corrosion on the edges
That discoloration on the porthole opening edge is aluminum oxide, and it’s the last thing you want to see creeping under new paint. A rotary tool with a sanding drum cleaned up the edge just fine.
More ancient corrosion
That paint just popped off.
Sanding it back to solid aluminum
The entire edge in this area was thick with corrosion, and a bubble extended 1-1/2″ under the new paint. As I was sanding it back to where there was no more corrosion, I found orange barrier coat under the Awlgrip primer, and corrosion under the orange coat. Which means that was more ancient corrosion from before the boat was sandblasted. Everybody just missed these spots.
Filler in the round porthole opening…and what appears to be a crack on the right edge
There’s supposed to be a step all the way around this opening for the porthole to fit into. But the fairing crew loaded it full of filler and never cleaned up the excess on the inside. As it is in the picture, there’s no way to install the porthole with that excess filler there. The closer I looked, the more it appeared as if there’s a crack in the paint.
Sanding it back very carefully
Still looking for the aluminum step edge, and I’m getting closer to the crack
Just a bit more and I’ll be at the thing that sure looks like a little crack
HELLO!
As soon as the sanding drum hit the edge of what looked like a crack, the filler popped off, confirming that it was, in fact, a crack. The corrosion here wasn’t too bad, but it definitely would have spread once the boat is put into service.
The starboard side isn’t as bad
But there was corrosion under OE orange barrier coat right at the step
Cleaned up and ready for primer
Max Cor CF coats the aluminum and seals the paint edge
Done!
Dry fitting the porthole
That looks great with the porthole dry fitted. There are a few spots where the Matterhorn white exterior paint needs to be touched up, and we’ll spray blue in these spots at the same time. I hope to have that done this fall, once the temperature drops to a more reasonable level. By then, the V-berth joinery should be done and the room will get sanded with 320 grit and sprayed with ICA top coat. Then it will be ready for the final porthole installation.
It was unfortunate that I had to dig into the paint, but it’s better to find it now than to have much bigger trouble years down the road.
Next up in our 1969 Chris Craft Roamer 46 Refit: Even More V-berth Cabinetry III
1969chriscraftroamer46 