paint compatibility question/problem

[jimmy]

I'm doing some repairs which involve a small corner of the cabin top which the previous owner had fiberglassed and painted with some kind of latex paint. My problem is that I don't have any latex paint and don't really want to get any since I prefer to stick to as few types of paint as possible and was hoping to use the same white marine enamel I use on other parts of the boat. I would also prefer to go sailing soon rather than strip the entire cabin top and paint it with enamel. So my immediate question is that if I touch up this part with enamel will it stick?

In the longer term, when I get around to repainting the whole top, are there any special considerations for cabin tops? It is currently a dull white and has some kind of texture that isn't particles, but some kind of painting technique almost like something had been peeled off it when it was wet leaving ridges and bumps (difficult to describe or photograph). I'm not sure if this is supposed to look like canvas (it doesn't) or is supposed to be non-slip (the cabin top rarely gets stepped on). Would dull/matt paint be desirable for sailing to prevent glare? Would it be worwhile to stick with latex? Although I am not crazy about latex I have to admit that aside from looking dirty and dull, it has held up well for the 4 years I have had the boat and I don't know how old it was when I got it (the paint).

Thanks

Jimmy
http://www.angelfire.com/indie/ealasaid/

[pipefitter]

Latex will stick to sanded oil base but not the other way around. I suppose it would stay for a little while as a touchup but i wouldn't paint the whole cabin top with oil without removing the latex. I dont see what is so bad about buying a little can of latex as you are only talking a few dollars. You have already spent more time posting the question here than it would have to run out and get some.

[Wild Wassa]

Something isn't making sense, to me ... (but then little does generally).

Latex (in the US), is what I call an acrylic based paint?

If so, oil goes over acrylic not acrylic over oil ... unless you use a linker like ESP over the oil ... this is not ideal for marine use and nothing beats wooding before painting.

It is common practice in the painting industry to use acrylic primers under oil based paints unless you have the time to use oil based primers of course.

Warren.

[capt jake]

Different terminology here on the other side of the world. I think we have crossed this conundrum (sp?) before. :) Boating terminolgy varies also I have noticed. ;)
Latex here has the term Acrylic added to it to denote improved durability, stec. Not sure about the axact make-up difference.

[pipefitter]

I remember the schedule for using 100% acrylic waterbased paint over raw wood being to use a coat of oil based primer or flat oil. The thought was that the oil based took longer to dry thus supposedly soaked in better. I think that has changed now being able to use a water based primer now as well. But initially,it was oil primer then acrylic. The acrylic did outlast alkyd topcoats and rarely mildewed or cracked. Acrylic is plastic and oil based paints dont stick well to plastic as far as I remember but I could be mistaken.

Also,maybe I am wrong about acrylic going on first as I have noticed it does soak in. But "latex" is basically vinyl. I dont think they are the same animal.It may be correct to use "acrylic" under oil based.

Ok,did some checking with a paint contractor I know. He laughed that anyone still uses alkyd. They use acrylic under oil to save 2 coats of oil based and the days of drying time. Also,he did say that when acrylic waterbased first came out,there wasn't acrylic primers as acrylic only came in low sheen. Not flat nor high gloss. Thats when I was using it. "Latex" is only used on raw masonry or wallboard anymore. They never use it on wood.

[capt jake]

My post was in reagrds to acrylic latex. It seems that 'technically' this isn't a correct name (though they market it this way).

[pipefitter]

There may very well be a paint that is both. When I was painting,there was only latex and oil. Acrylic was coming out at the end of my paint days or was just starting to be recognized by the old timers.Maybe thats why they label some as 100% acrylic.

[capt jake]

OK, I'm getting confused. :) I remember that you can't put lacquer over enamel, but you can put enamel over lacquer. :) No help in this case. ;)

[jimmy]

OK, I don't know exactly what kind of paint is already on there so maybe I shouldn't have used the word "latex". I know from scraping it off other parts of my boat that it is flexible and kind of rubbery unlike enamel which is usually quite hard as long as it has cured for a while. So I gather whatever it is I can't expect enamel to stick to it very well. Thanks.

[Wild Wassa]

Jimmy, if your paint is good and not with a chalky surface, if you rub a cloth with metholated spirits onto latex (or acrylic) based paints, the metho will dissolve the paint slightly and you will see it on the cloth. That is the best ways to help identify what you have ... if it is latex (now you have got me saying the word).

The expensive acrylic paints come with their primers in the paints nowadays. Ask you distributor if you need to use a primer. The reason why we use a primer under acrylics is to stop mildew ... that tell tale sign of mildew under the paint can be another way of identifying acrylic based paint ... if you are unlucky.

Warren.

[maa. melee]

Acrylic paint of oil may cause a disaster. An old clapboard house nearby, painted in oil based paint, got a coat of acrylic latex which lasted a while but then the whole lot flaked off, exposing bare wood...which I guess is good, since the house was now wooded and ready for new paint.

[pipefitter]

If oil based is sanded and washed with TSP,100% acrylic will stick well to it. Most people try painting over it without removing the chalk or keying the surface. Only time I ever saw acrylic fail with the peeling like you say,is when the dead paint wasn't removed. It will then,once started,will peel off in sheets like wallpaper. They make gloves and other microbial barrier implements from stretchy latex. Not the same as material as acrylic.

[Paul G.]

What about a primer coat of red lead then acrylic?

[Stiletto]

Some of you are answering a question that hasnt been asked.
Jimmy wants to overpaint a small area of latex with oil based paint.

My answer to the question is: Clean and sand it well and try it. As it is only a small area it probably doesnt matter too much if it has to be replaced next year.

Go sailing.

Fair winds.

[Wild Wassa]

"Some of you are answering a question that hasnt been asked."

Is that a problem?

It has already been answered, you are just repeating us. Pipefitter's first thoughts also needed attention.

Post some painting shots if you know better than the rest of us ... I paint oil over acrylic because I want my paintings to last a long time. The National Gallery of Australia collects my art. I sure as hell aren't giving them a dodgie job. I expect my paintings to last over 600 years ... before the conservators move in on them, to do a rebuild.

Oil over acrylic is standard practice ... it isn't a matter of giving it a try.

Warren.

[jimmy]

Thanks for all the replies, reguardless of relevance. I think I will just go ahead and try it as suggested since it is only a small area. If it peels right back off I will know better than to do the whole top. I'd rather go sailing and read through the mountains of info on painting when the weather turns bad again. Thanks

[Stiletto]

Jeez Warren, sorry if I stepped on your toes, I acknowledge you are an expert in the field.


Perhaps I should have just said I agreed with pipefitter.
I guess I included my distilled thought processes in my answer , what have I said that claims to know better than the rest of you?
If I have , then you should have called pipefitter on it as well, given that I basically reiterated what he said.

Apologies to all those I offended.

[pipefitter]

I didn't take any offense,stiletto. Some do reply abrasively and without the benefit of inflection via this internet,some are misunderstood. Some are even appalled that a subject may stray from the original question and it's like a rule around here. I don't think it's bad to hijack a little after the original question has been answered for conversation sake, afterall,the thread would just die anyways. I guess to Warren,it could have been possible to feel you were policing the thread after the fact with your opening statement. You ought to see some of the arguments I can get into with my gfriend on here for lack of better explanations. :)

[lesharo]

Latex is horrible to sand. As you mentioned it is rubbery, which is the qualityof latex and what makes it hold up so much better than oil. The oil over should be okay, but I can't imagine the finish quality of the latex being too good. Oil levels better, but also cracks better.