Bottom Paint??

[nemosuit]

I'm patching blisters and imperfections on the hull and gel coat of my 1978 MacV-22, and thinking about paint.

I'm seeing some poly paints say "For use above the waterline only."

For bottom paint, I'm seeing that there are different types because (in some) the ablative properties are affected by removal from the water: trailering, haul outs, etc.

So now I'm wondering: do I really need an anti-fouling bottom paint?

My use for the boat will be mostly day sailing; perhaps the very rare weekender. After which she'll be trailered back to my home, washed down, and stored in a dry shelter. I don't see much opportunity for marine growth to form on the lower hull.

Given those circumstances: is there some reason why I can't simply paint the entire hull (sides and bottom) with a good marine grade poly paint?

It's an older boat; not in the best of condition; and I'd like to get it back into the water with the best ratio of quality to economy possible.

What do you folks think?

VBR,

Pat

 

[MrBill_FLL]

if you don't keep it in the water for more than 5 days, I don't see a need for bottom paint... -not sure about poly paint... whether you could go over that later w/ something. I've got alabative... with a (2) barrier coats 1st.

go sail! and rub it down with a scrub pad! (even without paint) *unless you have bondo exposed.

I know Imron and sterling are used below waterline. (2 parts). and some epoxy paints... (even a 1 part type).

I'd ask a marina or locals on the paint... you sure don't want it flaking off... or not sticking... ugh!

sailnet has some good articles on paints.. or try the main board here....

 

[nemosuit]

if you don't keep it in the water for more than 5 days, I don't see a need for bottom paint... -not sure about poly paint... whether you could go over that later w/ something. I've got alabative... with a (2) barrier coats 1st.

go sail! and rub it down with a scrub pad! (even without paint) *unless you have bondo exposed.

I know Imron and sterling are used below waterline. (2 parts). and some epoxy paints... (even a 1 part type).

I'd ask a marina or locals on the paint... you sure don't want it flaking off... or not sticking... ugh!

sailnet has some good articles on paints.. or try the main board here....

Thanks Mr. Bill!

What I'm thinking of is marine grade Polyurethane enamel. Relatively inexpensive, comes in white, gray, colors, etc.

I'm downstairs working on the boat right now. On some of the blisters, the PO used what appears to be a proper marine grade epoxy filler. I've got just about all of those areas faired out and ready for paint.

But what I'm running into now is a whole lot of places where somebody used automotive Bondo, and didn't even mix it properly. Still gray in some places, and I can stick my thumb nail into it. :cussing:

I was going to take the stuff off with Jasco Gold Label paint and epoxy remover. Used it on Corvettes for years without damaging the glass. But that chemical process would require a lot of washing and cleanup afterwards. And the drydown time between spots would be time prohibitive.

So I'm down there with my 4" Makita and a stainless steel wire cup-brush, gently removing most of the soft mud. I seem to be getting away with it without damaging the glass below. No extreme friction heat, either.

Then I'm taking the last fine layer off with 60 grit on a 1/4 sheet sander. Using some marine grade fiberglass filler epoxy to fill in the blisters, and going on from there. But I had a thought.

QUESTIONS: in areas where the blisters are through the gel coat and the sub-surface laminate cloth is showing, should I coat those spots with fiberglass resin before putting in the epoxy filler; or should the epoxy filler sufficiently waterproof the spot all by itself?

Maybe I should paint over the repaired spot with a thin coat of fiberglass finish resin, to seal pinholes for better waterproofing, and be sanded smooth before paint? Or do you think that might flake off?

VBR,

Pat

 

[Sumner]

One thing I would do since you have done all the work on the bottom is use a boat epoxy barrier coat.

I'll be applying this stuff soon..

http://www.bottompaintstore.com/Tuf...-Primer-2GL-KIT-1284-2GL-KIT.htm?productId=42

... for $120-$150 I think it is well worth it. I'll be putting bottom paint over it for growth. The bottom paint won't do anything to stop further blistering, but the barrier coat will.

Good luck,

Sum

Our Trips to Lake Powell, UT - Kootenay Lake, Canada - Priest Lake, ID

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[nemosuit]

One thing I would do since you have done all the work on the bottom is use a boat epoxy barrier coat.

I'll be applying this stuff soon..

http://www.bottompaintstore.com/Tuf...-Primer-2GL-KIT-1284-2GL-KIT.htm?productId=42

... for $120-$150 I think it is well worth it. I'll be putting bottom paint over it for growth. The bottom paint won't do anything to stop further blistering, but the barrier coat will.

Good luck,

Sum

Our Trips to Lake Powell, UT - Kootenay Lake, Canada - Priest Lake, ID

Our Mac Pages

Mac-Venture Links

I'm thinking that's a good idea, Sum.

Up till now, the work I've been doing on the hull was about 90% above the waterline, and whoever did it did a pretty good job. All I did was finish sand and prime those spots.

What I'm encountering now on the bottom of the boat is a lot of blisters that somebody tried to cover with ill-mixed automotive Bondo, which isn't even cured yet after God knows how long. It's still soft enough to gouge with a fingernail.

So, I'm using a stainless wire cup-brush on a 4" Makita grinder, and very carefully removing most of the bad Bondo. Then I'm following up with a 1/4 sheet sander with 60 grit and (again) very carefully removing the rest of it until I get to the laminate below. So far, I think I've cleaned out the parts I've worked on without doing more damage.

Then, I'm cleaning out the blister cavities of all dust and stuff by wiping them out with an Acetone rag and letting it dry.

Then I'm using marine grade, fiber-reinforced 3M filler designed for fiberglass boat repair. I'm finding it takes about two layers of that to get the cavities pretty level.

Very tiny pinholes that might remain after sanding the 3M are being filled in with regular Bondo, but mixed properly.

I'm shooting over the top of that with a generic white primer by Derusto, just to keep it clean and sealed. I can sand it off later if necessary.

I saw one repair method that talked about painting the inside of the blisters with fiberglass resin, before filling. Others didn't say that was necessary. What do you think?

Okay now, the Barrier Coat. Is this like a good primer that has waterproofing properties?

Will it work under a two-part polyurethane enamel designed for boat hulls?

Does it sound like what I'm doing so far will have a reasonable chance of protecting the hull, or should I still prime with Barrier Coat before shooting the top coat?

What painting over the top of the repairs with a layer of fibrerglass finish resin, and sanding before doing the Barrier Coat? Good idea, Y / N?

Your opinion is muchly appreciated. Thanks.

VBR,

Pat

 

[beamreach]

I've always used Marine Tex Epoxy to fill blister cavities after I dried them out and cleaned them with acetone as you have done. Marine Tex fills it in one application and doesn't sag. Tapeing over the patch with a wide piece of masking tape helps it make even better contact while setting up and reduces the need for much fairing. Epoxy barrier coat for sure. Maybe two coats.

 

[Mick]

Just to through a little more into the mix. I have used the Rustoleum marine on a flying scott I had. It was only the topside paint but was well impressed with it.
They also have bottom paint. all of which are reasonably priced. You can get it through home depot. If not on the shelfs then they will order it for you . Takes about 5 days to get it in.
One thing on their paint check out the dry time between coats. Adherer to it.

 

[Sumner]

I do some car body work and use epoxy primers and high build primers designed for autobody work, but for the boat I would go with the barrier coats designed for that job like the one I gave you a link to or something like Interlux....

http://www.jamestowndistributors.com/userportal/document.do?docId=325

....or some of the other products like from Pettit.....

http://www.defender.com/product.jsp?path=-1|10918|296162|11453|311507&id=105646

I picked what I did because it required the fewest coats, was least expensive, and seemed to have the easiest application procedure. You need 2-3 coats of it. Some of the others require more than 2-3 coats. If the boat was going to be in the water all of the time I might of gone with one of the others.

If you put on the barrier paint then why not just use a bottom paint over it that would also give you protection against slime and growth? A hull paint won't. Use the hull paint above the water line.

Pick a bottom paint that works well with a trailerable boat and will work on a boat that is out of the water for some time. I'm using ....

http://www.bottompaintstore.com/Cukote-Biocide-Plus-Self-Polishing-Bottom-Paint-GL-3500-GL.htm

....since it was recommended for Florida and it is fairly hard so won't rub off as easy on the trailer bunks and is designed to work again after being out of the water for extended time periods.

There are others and if you want a brighter finish go with one of the Pettit Vivid colors...

http://www.defender.com/product.jsp?path=-1|10918|296162|11000|311497|368328&id=737847

... I almost went with it and would of it I had the boat on and off the trailer more. Check with the locals and see what works best in your area for a "trailered boat" (not one in a slip). Also all of this paint like automotive paints has to be applied withing certain time windows to achieve the proper bonding. Read the tech sheets and see what you feel comfortable with. They aren't cheap, but no paint is now and you did buy a boat didn't you and you know the old saying about boats, a..........

Good luck,

Sum

Our Trips to Lake Powell, UT - Kootenay Lake, Canada - Priest Lake, ID

Our Mac Pages

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[MrBill_FLL]

to me it depends how long you will keep the boat... flip it in a year or two, or keep if for 5+ years.

-sure don't want to have to come back to this....
my time is valuable... materials, not so much over time...


(-the old saying only a rich man can afford cheap tools comes to mind...)

imho, do it right and cry once...

 

[Sumner]

.......imho, do it right and cry once...

Love it, have to remember that one ,

Sum

 

[MrBill_FLL]

^


hey, that doesn't mean you can't go sailing now...

you can just wash it down... if the bondo is soft, getting it wet might actually help loosen it up..

(does sailing season shut down in the winter? -if not, might as well finish what you started, but going out sooner may make the work seem sweeter!)

 

[nemosuit]

Thanks guys! All makes good sense and I will look into the links provided to find the best paint I can get for the job.

Got the boat cheap and was trying to keep the restoration costs to a minimum; but I realize paint is probably going to be one of my major expenses.

Home Depot in Hilo doesn't have boat paint in stock, but I'll see if i can get them to order it for me.

Otherwise I'll either need to have it shipped in, or drive to Kailua Kona to buy some. Big factor there is which is more expensive, convenient, etc.

But no, we won't be sailing her just yet, Mr. Bill. I've got her pretty well dried out, under a temporary structure we set up next to the house to keep her out of the rain, the bad Bondo is coming off without too much effort; and I want to get her faired and painted before we go to the ramp.

Besides, vacation ended yesterday; I'm going back to work this evening. Will continue the repairs a couple hours per day before going in on my work days; and maybe some on the weekends. There's still a bit to do, but I think at that rate I can have the hull ready for paint in a couple weeks, maybe. We shall see...

As always, many mahalos!

VBR,

Pat

 

[Sumner]

......... I've got her pretty well dried out, under a temporary structure we set up next to the house to keep her out of the rain, the bad Bondo is coming off without too much effort; and I want to get her faired and painted before we go to the ramp...........

Hate to be the bearing of bad news, but you might want to check with some of the yards there about what you are doing. I've read of blister repair (google it) that to be successful needs the hull very dry, like dry to the point it has been out of the weather for months and the hull checked for dryness. I guess you have the possibility of trapping moisture in the blisters with the barrier coat and then still having problems down the road.

Of course life is compromises, so you might just have to try what you are doing and see what happens.

Our boat doesn't have blisters now, but the longest we have had it in the water has been 3-4 weeks. I'm doing what I'm doing to try and avoid all of the problems of dealing with blisters after the fact.

How long has your boat been out of the water? I'd probably just do what you are doing and see what happens. I can't see waiting around 6 months to a year to get it moisture free.

Good luck,

Sum

Our Trips to Lake Powell, UT - Kootenay Lake, Canada - Priest Lake, ID

Our Mac Pages

Mac-Venture Links

 

[Sumner]

On getting paint, there surely are West Marine stores over there and I'm sure checking around you would find other local suppliers of paint. Lots of boats in Hawaii and they need paint,

Sum

 

[nemosuit]

Just to through a little more into the mix. I have used the Rustoleum marine on a flying scott I had. It was only the topside paint but was well impressed with it.
They also have bottom paint. all of which are reasonably priced. You can get it through home depot. If not on the shelfs then they will order it for you . Takes about 5 days to get it in.
One thing on their paint check out the dry time between coats. Adherer to it.

Thanks Mick!

I checked with Home Depot in Hilo today, and they said if we can get the SKU number for the paint they will order it for me.

I don't expect you to have the SKU number for the paint (if you did, that would be great) but if you could tell me the following, I can try to find out on my own:

NAME AND LOCATION OF HOME DEPOT STORE YOU BOUGHT FROM.

ABOUT WHEN YOU BOUGHT IT (How long ago?).

NAME AND TYPE OF PAINT.

ANYTHING ELSE YOU CAN TELL ME: Price, available colors, etc.

I think with that informaton, if I get them on the phone, I can find out the SKU number and have my local HD order it.

Would probably save a lot of money in shipping costs!

Would really appreciate the help.

VBR,

Pat

 

[nemosuit]

Hate to be the bearing of bad news, but you might want to check with some of the yards there about what you are doing. I've read of blister repair (google it) that to be successful needs the hull very dry, like dry to the point it has been out of the weather for months and the hull checked for dryness. I guess you have the possibility of trapping moisture in the blisters with the barrier coat and then still having problems down the road.

Of course life is compromises, so you might just have to try what you are doing and see what happens.

Our boat doesn't have blisters now, but the longest we have had it in the water has been 3-4 weeks. I'm doing what I'm doing to try and avoid all of the problems of dealing with blisters after the fact.

How long has your boat been out of the water? I'd probably just do what you are doing and see what happens. I can't see waiting around 6 months to a year to get it moisture free.

Good luck,

Sum

Our Trips to Lake Powell, UT - Kootenay Lake, Canada - Priest Lake, ID

Our Mac Pages

Mac-Venture Links

Thanks Sum! I think you're right. The videos and articles I've seen about blister repair do speak of drying them out. Some say the boat should be tented; recommend heaters, moisture checking instruments, etc.

I think I'm pretty lucky in this regard. The boat sat at mooring for a long time, but hasn't been in the water since 2008. Most of what I'm encountering are spots that were already opened and filled. The most of what I'm having to do is remove (what I consider to be) bad filler and replace it with marine grade stuff. So far, everything seems very dry.

We do have the boat "tented" under a portable carport-like structure; it gets fairly warm in there, and everything is good and dry. I also have a large fan on the forward hatch, drawing air through the boat.

It's an old boat with a considerable amount of repair work needed to the hull. We got it practically free, considering the trailer is worth more than we paid for it. I'm trying to do an economical job of restoration, to get it back in the water and use it to learn to sail. So far, everything looks pretty dry in the spots I'm treating, and I think it's going to be OK for the intended purpose. Fingers crossed!

VBR,

Pat

 

[nemosuit]

On getting paint, there surely are West Marine stores over there and I'm sure checking around you would find other local suppliers of paint. Lots of boats in Hawaii and they need paint,

Sum

Yep, we have West Marine on the Kailua-Kona side of the island. Very expensive and shoots a day driving there and back. I'm looking for other, more economical ways to go. But it just may turn out I'll have to go over there for my paint.

I've been looking at The Bottom Paint Store you mentioned for a while now. If I can get a deal on shipping, that might be my best bet. Also trying to work a deal with Home Depot.

Many mahalos for your info! Muchly appreciated!

VBR,

Pat

 

[Sumner]

.......... So far, everything looks pretty dry in the spots I'm treating, and I think it's going to be OK for the intended purpose. Fingers crossed! ........

You are probably fine. If it was me I'd go ahead and do the repairs and start sailing.

On the paint, I realize it is expensive, but figure the cost difference from paint you know works and what others have used over 3-4 years and it isn't much, especially considering the alternative of having to try and take it off or repair it and do it again. When I do car work and now the boat I bite the bullet and try and get good stuff to begin with. The difference between $100 per gallon paint and $200 is only about $33 per year over 3 years. What is that 2 maybe 3 trips to MacDonalds.

I couldn't find where Rust-Oleum had a barrier paint and not much info on the anti-fouling and use on trailer boats. Some anti-fouling paints have to stay in the water to work and can't be dried out. I'd check on that if you were considering their paint.

Now for my new favorite saying courtesy of MrBill ...

imho, do it right and cry once...

c ya,

Sum

 

[nemosuit]

You are probably fine. If it was me I'd go ahead and do the repairs and start sailing.

On the paint, I realize it is expensive, but figure the cost difference from paint you know works and what others have used over 3-4 years and it isn't much, especially considering the alternative of having to try and take it off or repair it and do it again. When I do car work and now the boat I bite the bullet and try and get good stuff to begin with. The difference between $100 per gallon paint and $200 is only about $33 per year over 3 years. What is that 2 maybe 3 trips to MacDonalds.

I couldn't find where Rust-Oleum had a barrier paint and not much info on the anti-fouling and use on trailer boats. Some anti-fouling paints have to stay in the water to work and can't be dried out. I'd check on that if you were considering their paint.

Now for my new favorite saying courtesy of MrBill ...

imho, do it right and cry once...

c ya,

Sum

Yep on all counts. The idea of doing all this work, and then have it peel off, scares me. Looks like paint will be expensive. Just going to have to say, "That's how it is," and get on with it.

And if I sell the boat, I can always say to the prospective buyer that we bought good paint.

Gotta work tonight, but I'm heading down to "the tent" right now to do a couple more spots before I have to go to the "real" job. Thanks again for the input.

VBR,

Pat

 

[MrBill_FLL]

just some searched results from sailnet... it use to be a great resource..

http://www.sailnet.com/forums/gear-maintenance/67881-painting-florida.html

http://www.sailnet.com/forums/gear-maintenance/67677-boot-top-blistered-awlgrip-imron.html

http://www.sailnet.com/forums/gear-maintenance/67486-what-not-do.html

http://www.sailnet.com/forums/gear-maintenance/67503-tips-barrier-coating-interprotect.html

I'm sure no expert, but I do read a bit... I would think about epoxy paint.

if are going to spray, you can spray gelkote, but you have to clean the gun fast or get some cheap ones... even a few of those disposable ones. (rattle can type sprayer, but you add the mix)

or just barrier coat the bottom, and put an epoxy bottom paint or alabative on it.

but and Enamel? hmmm... I'd really ask on some other forms first... (like main board here, sailnet, or the boats us forum.)

someone must have tried this already...

(also google roll and tip painting

http://hubpages.com/hub/Roll-and-Tip-Method-of-Painting
http://hubpages.com/hub/How-to-Paint-Fiberglass
http://www.youtube.com/watch?v=4NKrw8iuQRs
http://www.videojug.com/webvideo/how-to-roll-and-tip-while-painting-a-bettle-cat

ymmv....