NS,
I have the
boat in a small
DIY yard here. Had the yard staff do he blasting. We used sand, for better or worse.
I had a couple of places where there were plate issues. One in the keel where there seemed to be voids in the concrete fill, and one in her haunches were I had a persistent
winter time only
deck leak. The keel holes I ground out and patched (not quite done, gonna do a little exploration there) and the haunches will need a bit of plate replaced.
I painted with PPG Ameron 302 zinc primer with PPG 235 BarRust on top. Not done, still have coats to do. After applying the first two coats of 302 I got some
blisters in the paint. Don't really know why.
We blasted one side, I wiped it down with acid, then with acetone, then painted. Next day did the other side. PPG gurus were nice, confusing, and not overly helpful. They think I got some contamination from salts on the surface either from the acid not being totally cleaned off of from the sand, or from the old paint, or...
Under the blister there would be paint on the
hull, usually. So it almost looked like a blister between coats. Weird. Never seen this before.
The verbal paint instructions are difficult. Blast, pressure wash with
water, dry with compressed air, paint before you get rust blush. If you did this it would take a LOT longer and be a LOT more expensive. When I asked about blush from
washing the said "Well, ya know, a little blush is OK".
The wiping with acid and acetone was real tough, nasty. So maybe I didn't do as good a job as I could. The boat had clear plastic covers, the dust is incredible, the acid wash was not too bad. The acetone wash was bad. Freaking cold on the hands and you MUST wear a proper ventilator, fumes are horrible. Then the first coat of paint goes on under a tarp which holds the paint fumes, which are again horrible.
I can't imagine doing the process PPG recommended. You would really need a closed shop to do the
work or you would have to tarp and remove each step, then there is the
water run off, and disturbing the dust with the compressed air. Practically I don't see how I could have done it much different than I did.
Also, they questioned my use of the zinc primer. I explained that is what boat builders recommend. They said it was OK but not where they would use it. Damned if I know where they WOULD use it.
Anyway, I ended up
sanding out
blisters on maybe a quarter of the hull, touched up the paint, then found some more blisters, sanded them out, then used the 302 and (because of the different color or texture?.) found a few more blisters which I just cut out with a knife and painted.
I have no complaints with the paint. Stuff happens.
Now I have a bunch of
interior work to do. The leak got water under the spray foam so some of that has to come out. Which meant I had to remove the
fuel tank, in 5 pound pieces. I will convert my empty keel voids to diesel
tanks. I got Ted Brewers blessing on that idea. That will provide good protection to the steel in the tanks. And essentially provide a double hull.
I also found some issues with the
engine mounts I won't go into. I'll have to redo the stringer attachments. The
engine is out while I treat and paint the areas underneath.
Slow going since December. Lots of
family obligations and bitter cold.
Hope I answered your questions. If not ask more.