Bottom paint removal

I am about to haul out my 1984 E38 and want to strip the bottom paint off to bare gel coat (2 coats of paint applied every 2 to 3 years). I would like to hear any ones experience in doing this with paint strippers such a Peel Away. Thanks, Peter

No easy way

I tried the stripper...Big messy job, goo and glopp everywhere. The stripper bubbled and loosened the first coat and maybe a bit of the second. (IT DID NOT JUST PEEL AWAY!), and yes I followed the directions, covering it with plastic and all).

The stuff was very expensive and I was disappointed. (Maybe I was hoping for a miracle). Other folks, I guess have had better luck, but my luck ran out along with the stripper.

Well, to be honest my boat is vintage 1974 and probably never been stripped bare. I spent at least two full days grinding away with 36 grit disc and a variety of other nasty measures including a heat gun and scrapers. (I seriously considered a sand blaster, blow torch and dynamite). I never did get it completely bare but I did get all the loose paint off and feathered the rest. I am kind-of a perfectionist and so it was hard for me to admit defeat but this was like trying to shovel all the sand off the beach.

Someone else (I know), is going to write-in and say how easy it would have been if I had only used Zip-off instead of Zap-off.
Well...I say, shove-off, there ain't no easy way.

I have'nt used any chemical strippers but did have my last boat sand blasted, water line to bottom of keel. We used crushed walnut shell and it took about one hour to remove 13-14 layers of old paint. This did not damage the gelcoat and left the bottom completly clean of any bottom paint. Saved a lot of time by not having to sand.

To good to be true?

Walnut shell sand blast? Hey that sounds good. I really did consider sandblasting but dismissed it because of damage to the gel coat. My E27 is still on the blocks so maybe I can be a perfectionist afterall. How best should I protect the new paint above the waterline whilst-ye-blastaway? (Probably should have blasted first). That bottom grind was the most miserable thing I've ever had to do. Thanks for the tip.

Very miserable

Like others, I took all the paint off my 1974 E27. I opted for the sanding method, and just went nuts with the nastiest grit I could find. It did take a while (week) , but it was definately worth it. I saw some wierd colors under there. Think of all the weight you save! I ended up adding an epoxy berrier coat first, and added a pigment to it, so in the future, when it comes time to sand paint again, I know when to stop.

We used crushed walnut shell and it took about one hour to remove 13-14 layers of old paint.

Click to expand...

Who is the "we"? Is this a DIY job (if so, where did you get the equipment) or did you hire a professional? Thanks.

The we I talk about is the owner of a company that does commercial painting and sand blasting for the oil fields in north eastern alberta.

Then I guess there's not much chance of getting him to pay me a visit in Connecticut! Thanks.

I'm presently doing a bottom paint strip right now on my '84 E-28. I really just meant to do my usual spot scraping and sand-off of the chalky stuff before putting on this year's coat. Don't know what the previous owner had on the boat but I've been putting on West Marine's most basic stuff at $35/gal on sale. Works OK in Connecticut's modestly fouling water over our too short season.

I ended up being able to take it off easier than I thought so I'm doing a general job.

What works pretty well for me is a wallpaper scraper with an already used blade. It has about the right balance of sharpness (or lack of) and stiffness. I hold it at a very shallow angle with one hand while putting heavy pressure on the head of the scraper to push the blade against the hull. I have put a few scratches but this was primarily while I was learning to keep the blade at a shallow angle. It's effectiveness might depend on the paint you use but it seems to just blast this West Marine stuff off.

In about 3-4 hours of work I've managed to clean off most of the starboard side including the keel plus most of the port side to a couple feet below the waterline. The complex curves near the stern are a bit trickier and I might have to use straight sandpaper there. Once advantage of scraping is that the chips produced are easier to clean off myself than the dust from scraping so I don't end up as Mr. Blue Smurfman. I have to admit that my right arm was so sore after the session that it's taken me two days to be able to lift it.

It's come back so far I even considered doing a bit more sanding and using stripper to clean off the little bits left and putting on a barrier coating. But that would probably entail a couple extra weekends of work and I'm itching to spash her in the river and run down to Noank. Also, I've already bought this year's bottom paint. If I went with a barrier coat I'd probably have to use some other type of paint. No sign of blisters on the hull so far. Maybe if I was planning on an extended cruise to southern waters it would be worth it.

Pressure Washer

I found that I was able to blast off a few layers with a basic $169. pressure washer from the local orange home improvement chain. It took some experimenting with attachments vs. closeness, but I was able to get some success. I am holding off on perfectionism until next year, when I plan to take it all offf and put a barrier coat and aim for a smooth bottom, and new paint. I like the pigmenting idea. I am putting the Makita that has been discussed on my birthday/Xmas wish list. (This describes it best, I have never used the seller, no thoughts, just found the picture to send to my honey to make sure I get the right one: http://www.mytoolstore.com/makita/mak08-02.html ). I want the cheaper one, it looks like it has better speed control. Then I will be able to sand, polish, and buff to my hearts contentment! Just my $.02 .

Watch out if your going to use a sander like that to sand the bottom of your boat!!! That will make the surface VERY unfair! I use a tool very much like that to grind into fiberglass for repairs of cracks that go through the hull... its more for removing material quickly and deeply... not removing material like paint.

What works great for removing paint is the following:

Use a stripper like Zip Strip, or one of those ones not for fiberglass... get a plastic scraper... and don't let the stripper sit on the hull for over 5 minutes... that combination will take off the old bottom paint quicker then marine strippers. However, I have had some real good luck with the expensive interlux stripper last time I used it. It actually ate up an epoxy barrier coat that was 10 mils thick.

If you are going to want to sand your hull clean of paint though, there is only one tool that I would recomend... a dual action sander for an air compressor, vibrating sander, or a random orbital sander.

A disc sander that is direct drive to the pad like you show is usually called a disc "grinder", not sander. I actually bought a 4 inch version of the one you show. The 7 inch gets to be very heavy to hold above your head after a while of grinding.

Walnut shells huh?

I took my 84 30+ down to gel coat with the old Richard paint scraper with the corners of the blades ground off. Worked ok but there seemed to be a black barrier coat that was factory applied. had to use chemicals to get this off. The only thing that I can say with certainty is that I will NEVER DO THIS MYSELF AGAIN!
Cheers!
Graham Cole

Graham,

But by doing it yourself one time you'll appreciate what your buying when you hand over those big boat bucks the next time you get a bottom job done.