Bottom Cleaning

[rtheriault]

What is the most cost effective, efficient and environmentally friendly way to remove bottom paint? I’ve read about Farrow blasting but is it commercially available (in Canada)? What are the best alternatives. Our yard does not allow open sanding.

 

[Comodave]

We had a previous boat soda blasted. It worked very well.

 

[syjos]

I hand scraped Sandpipers 40' bottom with a carbide scraper. Took 5 days.

There was 24 years of accumulated bottom paint, 1/2" thick in places.

Wore a full face mask for personal protection but was not required by the yard to tent the boat since there was minimal dust.

Had the hull blocked extra high to ease scraping.

 

[O C Diver]

When I did my refit, I chose to take the bottom down to the gelcoat and then apply barrier coat and finally bottom paint. If that's your intention, sandblasting is probably the most time and cost efficient. It did a very good job cutting through all the layers of paint on my boat

Ted

 

[Datenight]

I did the green boat, a 37' trawler with a scraper and paint stripper. This was in the days when methylene chloride was the active ingredient. Not sure how well todays stripper will work.

Did not bother with "marine" stripper as it is very expensive, took a long time to work and was not as effective. I did rinse each section with water to neutralize it as I went along. No negative reaction at all with the fiberglass.

A tarp was laid out under to capture the detritus. Since it was dampened with the stripper no problem at all with dust. When finished I sanded the bottom with a Fein 6" orbital sander and vacuum. In my opinion the Fein machines have superior dust collection. Next was barrier coat and paint.

Not sure what you mean by open sanding. Can you use with a machine with dust collection and a vacuum? Would a tarp under the boat and plastic taped above the waterline and draped satisfy them?

It's not highly skilled work but it is tedious and wearing on the arms.

Good luck,

Rob

 

[Comodave]

I stripped one boat, never again. Way too much work and what a mess. I had one soda blasted and it was great. They charged $35 per foot. When they were done I had about 2 hours of touch up sanding and it was ready for the barrier coat. Way better and so much easier.

 

[Bmarler]

I hand scraped Sandpipers 40' bottom with a carbide scraper. Took 5 days.

There was 24 years of accumulated bottom paint, 1/2" thick in places.

Wore a full face mask for personal protection but was not required by the yard to tent the boat since there was minimal dust.

Had the hull blocked extra high to ease scraping.

what yard, if you don't mind my asking? i don't think i could do that in olympia.

 

[syjos]

what yard, if you don't mind my asking? i don't think i could do that in olympia.

Hylebos Marina in Tacoma in 2010

The yards do not get as concerned with scraping since less airborne dust.

I swept the scraped paint debris off the tarp every 15 minutes to avoid kicking the debris around. And to rest my arms.

Sanding required a dust collection system. Without a dustless sander, tenting would be required.

 

[rtheriault]

Thanks for all the comments and suggestions. Does anyone have experience with CO2 or the Farrow method.

 

[Datenight]

I stripped one boat, never again. Way too much work and what a mess. I had one soda blasted and it was great. They charged $35 per foot. When they were done I had about 2 hours of touch up sanding and it was ready for the barrier coat. Way better and so much easier.

i dont think i would do it again either!

Rob

 

[Comodave]

Yes, it was pretty brutal and it was in Tucson so it was only about 110 degrees…

 

[Bmarler]

Hylebos Marina in Tacoma in 2010

The yards do not get as concerned with scraping since less airborne dust.

I swept the scraped paint debris off the tarp every 15 minutes to avoid kicking the debris around. And to rest my arms.

Sanding required a dust collection system. Without a dustless sander, tenting would be required.

olympia (swantown) doesn't allow any kind of removal without a vacuum system, scraping included. the exception would be if you tent. i had a crew needle gun the entire bottom of my steel boat inside a tent i made, and was lucky to get approval for that. they wouldn't allow any blasting, tent or not. i'll be trying out different yards in the future to try to find one that's a little more relaxed. they're just so darned close to me, the convenience is nice.
i was cleaning up every night to try to keep the mess to a minimum, but it was really touch and go. the crew had little regard for keeping the mess contained and we ended up actually scrubbing the asphalt and vacuuming up all the sludge. i have no idea what all the debris weighed, but it was absolute torture.