sanding bottom of boat

[Gerard1970]

Ok guys, I am new to the forum and would like to start by saying that you guys are very knowledgeable. I am new to the anti fowling paint and have a few questions. I recently bought a boat and noticed that the paint was chipping off the bottom. I have been scraping the bottom for 2days now and am slowly getting there. My goal is to start from scratch, since 2 different types of paint were used and not very compatible. I have sanded and cannot tell if I removed any gel coat. When I scrape it off, I am getting a smooth, Brown colored look. I am guessing I want to keep this, correct? Second, if I remove the gel coat by accident, what steps AND products ( sealer, primer?) Would I need to do/ use before new paint goes on? Thanks for the help

 

[sphelps]

Re: sanding bottom of boat

Take a rag wet with acetone and let it sit on the painted area for a while . Might be difficult to do under the boat but if you work at it it should take whatever paint off . Acetone will not take the gell off .

 

[Thalasso]

Re: sanding bottom of boat

Just sand it and remove all loose bottom paint. Then repaint. Most bottom paint is compatible. (Ablative with Ablative)The brown is probably a primer that should be over a barrier coat. No need to be scraping hard enough to gouge the gel coat or fiberglass. You don't need to be putting acetone on there.Acetone isn't going to set on anything for any length of time.It has a quick evaporation time If it's that bad where you need chemicals to do the job get it blasted and start over.

 

[Chris1956]

Re: sanding bottom of boat

Gel coat on the bottom will usually match the area above the painted part. If it doesn't match, it could be a primer or barrier coat.

Lots of boats were never primed or barrier coated. Usually the AF paint will fall off in large patches, due to residual mold release wax and improper hull prep.

 

[sphelps]

Re: sanding bottom of boat

Just sand it and remove all loose bottom paint. Then repaint. Most bottom paint is compatible. (Ablative with Ablative)The brown is probably a primer that should be over a barrier coat. No need to be scraping hard enough to gouge the gel coat or fiberglass. You don't need to be putting acetone on there.Acetone isn't going to set on anything for any length of time.It has a quick evaporation time If it's that bad where you need chemicals to do the job get it blasted and start over.

The acetone rag was to just determine which layer was the gell coat as to not sand any further . I was not suggesting you use it to strip all the paint . I assume the op was thinking the brown stuff was the gell .