Cleaning the bottom of all paint to barrier coat

[Cmount]

Anyone have any recommendations to clean all the paint off the bottom of the boat? I was originally going to soda blast but in reading am a little scared. I am now thinking paint remover. Any guidance would be appreciated.

Nasty job for sure, but I think I need to do it as even though I sanded heavily last spring. The paint was still chipping off when I can out for a quick summer short haul wash down with the pressure washer.

Who knows, may pick up some speed as well.

[todd brinkerhoff]

Soda blasting is the preferred way and quickest. I haven't found a great paint remover, and you end up sanding A LOT.

[jimbo36]

Soda blasting is the preferred way and quickest. I haven't found a great paint remover, and you end up sanding A LOT.

x2 on that advice.

[comodave]

I have done the stripper and sanding route... Not much fun, terrible work. My F32 had a very thick buildup of bottom paint. I had it soda blasted and it came out great. It was not cheap, but I have had 2 shoulder surgeries and would not even consider the stripper and sand method. It was worth every penny to have it done.

[captainmaniac]

A lot of marinas have rules about what you can and cannot do, as a result of the 'hazardous waste' that needs to be disposed of (because of the stuff that is in the existing antifouling paint) ... Check on what options you will be allowed at your own or a nearby facility before going too far down the path.

When I did mine I tried a different kind of stripper system (Peel Away - you apply stripper to the paint then put a special paper over top, keeps the air out, traps the stripper in, etc... After 24 hours you just peel the paper off and the paint is supposed to come with it), but thanks to a leaky shed roof and some rain, the system failed catastrophically... Don't know if Peel Away itself doesn't work, or just that when you manage to get bunch of water in between the paper and hull the paper (and all the stripper attached to it) fall off, and almost on top of you!

Anyways... plan B was manually scrape and sand. Total job time : 100 hours, including the re-paint (Primer, and 4 coats Interlux Micron CSC).

[comodave]

I tried the Peel Away, could not get it to stay adhered to the hull long enough to get all of the bottom paint off. The sheets would be too heavy with the stripper and the bottom paint to stay on the hull. It was pretty expensive as I remember and I still had to do lots and lots of sanding. The sanding is a horrible mess, you get covered with the debris and it is not good for you. I think that it cost about $900.00 to get the bottom soda blasted. I spent several hundred trying to get the stripper to work on the previous boat and still had days of sanding. I will never try to do the stripping again.

[captainmaniac]

I tried the Peel Away, could not get it to stay adhered to the hull long enough to get all of the bottom paint off. The sheets would be too heavy with the stripper and the bottom paint to stay on the hull. It was pretty expensive as I remember and I still had to do lots and lots of sanding. The sanding is a horrible mess, you get covered with the debris and it is not good for you. I think that it cost about $900.00 to get the bottom soda blasted. I spent several hundred trying to get the stripper to work on the previous boat and still had days of sanding. I will never try to do the stripping again.

Can't remember my costs for the Peel Away attempt, but do know that after scraping and sanding - even with ventilator on - I was blowing blue snot for over a week. I have socks that are STILL stained blue from the old antifouling dust, so many years (and so many washes) after the fact. A bit worried about what's inside my lungs, but I will probably die from something else so what the hey.... When I tried the system I applied the stripper and paper, and then used painters tape to tape the edges of the paper together and to the hull. I figured things failed because of the rain water, but maybe the whole thing was fundamentally flawed. Having said that, I had 2-3 people tell me it was an awesome system and worked well... so don't know for sure.

[jimbo36]

What kind of barrier coating will you be applying?

[Cmount]

I spoke to Pettit yesterday at the Newport Boat show, and since I like the hydrocoat product, I will be using their barrier coat. apply three times. Pettit Protect in grey to be different than the gel coat.

[P-Dogg]

Why do you want to apply a barrier coat? Do you have a problem with blisters?

[Cmount]

I won't know until I get the 38yrs of build up off, but I think that is the best plan once I am down to the glass.

[jimbo36]

Cmount, you would be correct. until you assess what needs to be done to remove the old anti fouling the condition of the existing gel coat will determine what needs to be done prior to bottom paint. We do several bottoms for customers every year. Blasting is our method of old coating removal. We have 2 companies that provide this service to our marina. Soda blasting is an option along with co2, walnut shells and other materials but we find sand to be the best. A light powder like sand is as gentle as soda and less expensive. It is important to hire a blaster who does primarily boat bottoms as we find them most knowledgeable as they proceed and can judge how aggressive they need to be on each job. Blasting will remove some gel coat in the process so a barrier coat is a must. If the bottom required a harsher blasting (ie; blisters) we fair out and skim coat with epoxy x2, than apply 4 (minimum) or 6 coats (recommended) of InterProtect 2000. A combination of white and grey for each coat helps avoid missed spots. The directions must be followed to a tee between coats using the fingernail method. No matter what, it is a big job. Many areas require anyone removing anti foul have a license and proper disposal of the old paint is necessary by law. Good luck.

[LandVF36]

I don't know what you read that was negative about soda blasting, but for me, its nothing short of a miracle! I have had far too much time with strippers and sanding to ever do it again. Also, if you do continue to sand, you are crazy if you don't have a positive pressure mask. Just a strap around the neck is never going to save you. Bottom paint is some nasty stuff. You should also have a full body suit and shower immediately afterwords (and throw away the socks).
A couple years back, I had our F36 soda blasted. The guy was all suited up in a pressurized suit, and took her back down to the gelcoat. There was not a single blister, and I liked it that way. So, I put 3 coats of epoxy barrier coat back on. If you do this, use a different color for each layer. I went with white, gray, white so that over time I knew if I saw gray, i needed to do some work again. It turned out perfect and instead of the annual flaking I used to have, i just do some clean up at the keel and some "lipstick" around the waterline each year.

[yorklyn]

I used a chemical stripper. Trust me have someone soda blast it for you. Its money well spent.

[Cmount]

Thanks to everyone who has posted. Please continue to do so, I think I will look for a soda blaster.