Bottom paint prep, chipped paint

[nickmerc]

You will probably be OK just sanding with 60 or 80 grit down to the barrier coat. Most likely the barrier coat will be a different color than the bottom paint. Just be sure to sand down to the barrier coat, not through it. If you do, you can patch it. Depending on how old it is you may want to sand down to the gelcoat too and start over.

My old bottom paint was not bonded well so I was able to use a scraper to remove it down to the barrier coat on 80% of the surface.

[T37Chef]

Jos,

BTW, there is a good soda blaster guy in the Pasadena area, your yard probably knows him, "The Sand Man". I think I paid $580 +- to have my 37' boat blasted.

[josrulz]

Originally Posted by T37Chef

Jos,

BTW, there is a good soda blaster guy in the Pasadena area, your yard probably knows him, "The Sand Man". I think I paid $580 +- to have my 37' boat blasted.

Would soda blasting take off the barrier coat too? And does he do soda blasting on location, as in outside of Pasadena? Not sure we really want to go that far at this stage, but it would be good to know.
Thanks!
-J

[sailingdog]

No, not if it is done right.

Originally Posted by josrulz

Would soda blasting take off the barrier coat too? And does he do soda blasting on location, as in outside of Pasadena? Not sure we really want to go that far at this stage, but it would be good to know.
Thanks!
-J

[chef2sail]

I have also used the sand man with great results. Took off alll the old paints with no damage to the barrier coat at all. Jos just curious...our bottom paint lasts two years and we are in similar areas. Do you do any maitainence on it during the year such as use a diver or dive and maintain it yourself. Can you touch up you chipped area and get another year out of your paint instead of just adding a few new layers to it?

Dave

[CLucas]

Good thread, especially since I'm also facing this project in the spring... Haven't priced out soda blasting but suspect it may be beyond my budget. Thoughts on sanding alone vs starting with a chemical stripper (e.g. Interstrip or Peelaway)? I have Micron Extra (abalative) on my bottom but have some areas where the paint hasn't adhered well and is flaking.

[josrulz]

Originally Posted by chef2sail

I have also used the sand man with great results. Took off alll the old paints with no damage to the barrier coat at all. Jos just curious...our bottom paint lasts two years and we are in similar areas. Do you do any maitainence on it during the year such as use a diver or dive and maintain it yourself. Can you touch up you chipped area and get another year out of your paint instead of just adding a few new layers to it?

Dave

Hi Chef, we had a diver under the boat about mid-way through the year, and when we hauled the boat, the bottom was actually pretty clean. I probably should have made the yard just wash lightly, because there wasn't much need to hit it hard.

I would think that if we sanded and touched up the keel and strut (which would mean another coat on them probably), and then just sanded and touched up where the chips are on the hull (not many), then we'd be good to go. The paint appeared to be in good shape before the wash.

I'm just surprised the power wash took off so many chips. Pounding into the chop on the Chesapeake didn't cause it, so it's not like the paint was just "loose".

It would be nice to get another season out of it, then I can sand off more or even soda blast it next year when it'll need more fresh paint anyway.

Just out of curiousity, since the chips are more on the keel and the strut, could the paint flaking there be a galvanic thing? Or am I thinking too hard?
-J