Bottom paint

[rdhill]

I purchased a 1977 Com-PAC 16 last fall and have been fixing ever since. The bottom looks and feels like it has a coating of dried fresh water algae. I began to scrub it off with dry wall sanding sponges and soapy water and it comes off. However, the water turns blue on the bottom and the bucket. Am I ruining the bottom? Is the bottom paint poisonous? I will be in fresh water, at least this year. What should I repaint with? Thanks all. I just started reading posts and have learned gobs already.

[mikew]

Rd, the bottom paint you are scrubbing off is of the Ablative type - it has copper compounds in it that are toxic to marine growth and is designed to wear off and expose fresh surface to keep working. You can lightly scrub it and if there are no bare patches of gel coat showing leave it for another season. If most of it is gone you could scrub the rest off and leave it since you are in fresh water and may only get some algae growth ( if left in the water), or you could recoat it with new bottom paint. I keep my boat in a lake during the summer and have had good results with Pettit
Hydrocoat, a water based bottom paint. One quart covered my Cp-16 with two coats.

Mike  

[skip1930]

I agree with mikew

What your washing and scrubbing off is an ablative paint designed to 'fall off' taking with it the marine growth.

Way too much work, but if you ever get the hull down to clean-dry-and smooth white fiberglass consider an epoxy barrier coat and call it good enough for fresh, non-salt- water.

Give her a lick and a promise and slap on another coat [one quart] of any ablative paint and call it good.

Additionally ... wax on-wax off~wax on-wax off~wax on ... leave wax on below the boot stripe.

skip.

[MacGyver]

Just a note, sometimes highly chalked bottom paints will come off like ablatives. The color difference you describe is similar to this situation. At any rate it is bottom paint that is coming off, and that can / may be toxic. By washing it off, dust is not a problem, but having it on your hands is, although the absorption rate through skin is much less than that of in the lungs.

Be careful with paints you don't know, in any situation, in order to keep yourself safe. A word of safety, each persons body can take only so much of certain things, for instance, lets take Interlux 2000 for a moment for the example. Years ago we barrier coated outside, and was never told to wear masks. At some point I ended up getting horrid headaches, and learning more from the representative, I found we should be wearing organic vapor masks. Now, I am so saturated so to speak, that my body rejects it when I don't wear a mask, by making me sick. 2 other guys around the same stuff, don't have that issue, and only one of them will wear a mask like I now do just because it is safer. They have been around the stuff longer than I as well, so that shows that they are able to withstand more, before ultimately they are like me.

Just something to think about when working with paints.

Mac

[skip1930]

I don't think the really bad paints containing metal are sold anymore by law?

Really don't know. Or if they are, the cost has been artificially hiked up to a point where nobody buys them.

Knock off the loose stuff and slap on the new stuff.

skip.

[brackish]

I don't think the really bad paints containing metal are sold anymore by law?

Really don't know. Or if they are, the cost has been artificially hiked up to a point where nobody buys them.

skip.

Not so much metals as it is Isocyanates which is a component of the catalyst of many two part paints particularly polyurethanes.  Dangerous to the respiratory and central nervous system if sprayed on a regular basis without protection.  Trade names you would recognize would be Imron, Awlgrip, Perfection Plus, and others.  Really should use an air supplied mask if using every day or at least a good NIOSH vapor mask if using occasionally.  Different people have different sensitivity to them.

[rdhill]

Thanks for all the good info. I think this year I'll keep wet scrubbing and maybe paint when the boat goes in the garage for the winter.

[mattman]

Here is a link to get you started-antifouling paints contain a biocide and in no way harmless to us. Please read, do a little more research, and take necessary precautions.
https://www.auroramarine.com/ask-the-skipper/forum/antifoulingPaintToxic.html