Help painting the hull mistake? Hubby might kill me that I'm taking on too much!

[1966 Contagious]

Hello,
New to painting boats, just made the mistake of doing a little sanding on my 1966 50' hatteras, after finding out I should have deglazed the wax off first. Thank goodness it really wasn't a lot of the boat. Is that going to make that big difference before I deglaze the rest of my yacht. I used 100 grit on a grinder sander. Now how do I fix that mistake help help : ) Let me say I'm a toolmom, handy went to school for carpentry/cabinetry, I'm cheap don't want to pay 80.00 hr yard labor. This all started because the rub rails are really looking cruddy and I was worried it can wait another 2 years to be painted, since it's hauled out for bottom paint now it needed to be addressed. I plan to rent a scissor lift for all the work. Going to use Pettit easy epoxy paint.

[MikeP]

NEVER sand before using an appropriate solvent to remove wax. Otherwise the sanding just moves the wax into the sanded paint and subsequent painting will fail. If silicone is involved, it is EXTREMELY difficult to eliminate and fish-eyes in the paint are the typical result and hard to repair.

PrepSol - http://pc.dupont.com/dpc/en/US/html/...9295_3919S.pdf - was the "goto" solvent for pre sanding for as many years as I can recall but I have to admit I haven't done that work in the last couple of years so there may be something else that is now considered a better choice. In any case, solvent wash BEFORE sanding is mandatory for good paint work…whether it's a boat, a car, an airplane, or your new DIY bucket sub-woofer!

[1966 Contagious]

Thanks Mike or do I call you Skipper? I know that now and yes I will never do it again. It was a few small spots. So how do I fix it?

[bostonhatteras]

Sodium hydroxide, otherwise known as lye, obliterates silicone. It is one of the few compounds that will. Purple industrial cleaner at Home Depot is a good source. Water sheeting on a surface indicates a lack of wax. Beading of water indicates presence of wax.

[Cricket]

100 grit paper is very aggressive for sanding anything that's going to end up finish coated. It's going to take a lot of priming and sanding to fill the gouges from 100 grit. I'm Assuming your sanding the wood rub rails? Unless you're just touching up the bad spots that's a pretty huge job for 1 person, especially if you run into some surprises along the way. Don't forget to post some pictures.

[1966 Contagious]

I only used 100 on the hull in areas that were chipped or cracked and then I will epoxy them by feather ing them out and lightly sand them. Probably 10 small spots that I used it on. So the wood rub rail has some cracking and peeling paint to fix. I feel better after reading everyone's input. I will use a good cleaner and then deglaze it.
After I deglaze it i have heard that acetone is a great last cleaner right before painting is this correct?

[davidwigler]

Do you have a sister?

[jim rosenthal]

The paint system you are using should have a final cleaner specified. I'll defer to Mike and the more experienced painters here, but when I was painting the topsides of my boat (rolling and tipping AwlGrip) I used their degreaser-prep solution- AwlPrep. I did not used acetone or lacquer thinner. This is not the same thing that you use to remove wax or silicone.

It sounds like the problem you now have is twofold- deep scratches in the finish, plus wax or silicone in them. I suppose the answer to that is to first scrub with a degreaser and then alternate sanding and degreasing until you have a reasonable surface for beginning to prime for a finish coat. If I were sanding that area I think I would be using 220 and finishing with 320 before I started laying on any paint.

[MikeP]

What Jim said is probably the best advice - use the prep/degreaser solvent recommended by the paint-maker. As far as cleaning the sanded areas, all you can do is use the solvent liberally and work it using a rag with a decent bit of nap - like a washcloth. It WILL remove the wax though it may take a lot more rubbing/solvent than it would have if done before sanding. If there is wax with silicone (or silicone in any form at all), then, as noted, it will be much more difficult and will probably require a solvent designed for that purpose…or lye! I did not know that lye would eat silicone!

As far as sanding grits…well 100 does seem a bit heavy but if that's what's needed for the initial work, then so be it. It means, of course, that more sanding will be required to get to a grit where primer/paint can be applied without showing sand scratches. 100/240/320 or 400 will do the job.

[1966 Contagious]

Do you have a sister?

Yes but she is not a toolmom : ) And has a boyfriend : )