paint problem

[GC]

I have a problem with the paint above the water line. I used 3M marine sealant 101 caulking for my seams. The problem is I used a good oil based alkyd enamel paint. It went on just fine but the paint has never dried over the seams even after two weeks. It appears there must be something in the 3M caulking that reacts with the paint not allowing it to dry. Any suggestions, what exact paint should I be using to solve this little promlem.

Thanks

[Bob Cleek]

Yes there is a problem with paint drying over polysulfide seam compounds. I don't know that there is a solution from the direction of a paint that will stick to it and dry properly. You may be looking at removing that 101 and using a proper seam compound for the job. Sorry... maybe somebody else has a solution.

[pipefitter]

What is the sealer/caulking actually doing?Is that what makes the boat watertight or is it for smoothing seams for painting?What kind of planking method?If the caulking is just for the paint above waterline,you can use an exterior siding caulk that is compatible with the paint.Even if that goo were to dry,it would end up shrinking differently than the paint and the paint would develop hairline cracks over the caulking.After a time,slivers of paint will fall out of the joint when you wash the boat etc.Also,any of the modern "paintable" caulks with the many years of life expectancy labeled on the tube are kind of strange to use on detailed paint surfaces and are really designed for use with water based paints.It does last a long time though.It shrinks to nothing,skins over enough to paint it but still stays soft for a long time.

Oil based painters caulking will shrink and crack and would need to be replaced about every 3 years which is about the life of an exterior oil paint job,realistically.Not good for large seams but it does one of the neatest jobs and is about the easiest to remove when it is repaint time.

Some can tell you of better products but the ideal product is what lasts as long as your paint does.I dont want a 50 year product on something I have to redo every few years. It ends up being hard to sand around or scrape around and gets damaged from the process.

To add...Oil based painters caulking will come out of the joint in crispy chunks and the remaining leftovers can be quickly removed to nothingness with a heated putty knife.The modern caulks will leave films and parts that have to be carefully razor bladed off and doesn't sand worth a damn.Anything that you don't get off will scream out at you when you repaint/recaulk.

[ 01-13-2006, 01:49 PM: Message edited by: pipefitter ]

[Peter Malcolm Jardine]

The original compound between the seams on your Chris is not polysulfide. The carvelling lines were filled with a much more stable compound, I believe interlux still makes a compound like this, altho the name escapes me.

I don't know what sticks to the 101, but you seams topside will blob in and out with the weather unfortunately.

[imported_Jimmy]

I took a quick look at the 3m website and they made mo mention of being able to paint over this product, which makes me think it is very difficult or impossible. Hopefully somebody knows of something that will work, otherwise you will either have to live with your choice or replace all of it with a proper seam compound.

[GC]

Interestingly enough just below the water line where I used this same product and painted over it with Interlux anti flouling paint everything worked just fine. The paint completly dried over the caulk. The products were sold to be by a marine store I thought was knowledgable, I told them what I was doing and they sold me the items including the 3M 101. Tell me what should they of sold me, could someone advise the proper caulking. Its only 1/2 painted so its not to late to get the 101 out and the proper stuff in.
Thanks

[imported_Jimmy]

If the search engine was working properly you would have hours or days of reading to do on seam compounds. Try doing the alternative search method. When I do it I will use either red lead putty or one of the similar prepared seam compounds like the one by interlux, but there are lots of people who wouldn't go that route.

Oh, also, we are talking about seam compound, NOT caulking. If you used that 3m stuff as caulking your boat probably isn't safe to leave the dock.

[ 01-13-2006, 04:43 PM: Message edited by: Jimmy ]

[Bob Cleek]

The proper product to use is Interlux topside seam compound (white). Finish dings, etc., with Interlux glazing compound, or the equivalents. 3M 101 is not intended for use as a finish seam compound. It is made for use between the seams on caulked decks, and for that purpose can only be considered as "fair." Teak Systems seam compound is a much better deck seam product. Don't expect that just because you buy something from a "marine store" they know their ass from a hole in the ground. That guy in the "big box" chandlery might have been selling shoes the week before!

[GC]

I contacted 3M they said the product is OK to use
and can be painted. The paint must be a two part flexible catalyzed paint. The choices are to remove it recaulk & repaint or leave it and use the paint they suggest.

[corob]

HI all, you just need to seal the caulking before you paint. I forget what its called, but the stuff in the caulking that keeps it flexable, sucks all the dryer out of the paint.
Seal the caulking with Capitans varnish-It really works great to seal epoxy for painting too.
Corey

[Bob Adams]

Get some of the 2 part paint they suggest and use it as a "primer" on the seams. Funny, I've had this problem on 3M polysulfides, but never with Sikaflex.

[GC]

Thanks for the comments, I will discount Jimmy's comment on the boat no being safe to leave the dock. I feel it will be more prudent to take the info supplied by the 3M engineer as more thought out and factual. I was able to seal the seams using an industrial formulators flexible cold cure marine epoxy. It went on fine dried properly, the sealant remained very stable and most importanly the paint dried just fine over top. The boat will see only fresh water use on calm days so I am confident this system should work fine.

[imported_Jimmy]

Discount my comments if you like, although I think it is a little rude to say so. I was just making a comment on your terminology while at the same time trying to make sure you didn't make the mistake of replacing your caulking and seam compound with just the 3m stuff. Caulking (usually cotton) is a structural part of the hull and leaving it out is a big mistake. The fact that you used the 3m stuff in your seams indicates you may not be working with the best information, but I won't bother giving you any more advice if you are just going to discount it. Good luck.

[Thad Van Gilder]

hmmm. yes, I have to agree. a carvel planked boat without cotton in the seams is a bad idea. But is it a carvel planked Chris? I dunno. GC didn't say. Most of the Chris's I have worked on are batten seamed, in which case, there in no need for cottom and cotton would probably be bad for the battens.

-Thad

[imported_Jimmy]

Fair enough. It would have been more polite to indicate that the boat had been properly caulked before putting the 3m gunk in, or that the construction method did not use caulking, rather than saying he was going to discount my comments. Although it seems like he either didn't read them completely or didn't understand them.

[GC]

Sorry to upset Jimmy. To say the boat was unsafe and should not leave the dock was at best a speculative comment and maybe should not have been made. Certianly if you feel the 3m product is inferior to that of others is a valid comment but to suggest it would create some sort of a castastrophic failure thus suggesting the boat should not leave the dock, well that was a reach at best. I simply took your comment to the engineers at 3M and was told by them the product under those conditions is a stable product and that its properties are very similar to another 3M
products that haved proved to be very good in the marine field. This one unfortunately is not easily paintable. In any event no one has been able to suggest an exact product that can be or should be used. We have heard about products from interlux seam sealers, to common exterior house hold exterior calk. I am in the middle of the praries in Canada where interlux products are not readily available. Several products shown on US web sites are not even available here. The interlux catalogs of two marine suppliers on the west coast do not even show the products advertised on the Interlux web site. I have to work with products readily available to me. Once again sorry to Jimmy but when the statement about being unsafe to leave the dock was made I was left no choice but to follow up with 3m.

gc

[imported_Jimmy]

I don't have much to go on, but judging from what you have written is still seems like you don't understand what I was talking about. I'm not trying to be mean. I highly suggest you do some reading about caulking wooden boats. The work "caulking" does not have the same meaning as elsewhere. The phrase "not safe to leave the dock" was poorly chosen and diverted attention away from the issue, for which I appologize.

[ 01-16-2006, 10:55 PM: Message edited by: Jimmy ]

[Thad Van Gilder]

we still don't know if the planking is carvel or batten seam...

[GC]

Thanks again guys I do not know if its carvel or batten seam. Prior to painting the boat I took a tool and removed the loose material between the planks. The area between the planks was between 1/32 and 1/16 of a inch and maybe 1/8 to 1/4 deep, this leads me to believe the planks are of carvel design. I replaced the material with the 3M 101 sealant. Once sanded it gave me a nice level surface to paint the product boned very well. The areas inquestion are about the width of a quarter, as mentioned its not very deep. I was only concerned with removing the loose material and did not put alot of pressure on the tool when doing this job. I may be using incorrect terms when I reffered to this process as caulking the hull. This is also why I was suspect when Jimmy suggested the boat was no longer safe.

gc

[imported_Jimmy]

If you didn't pull out the caulking (cotton or black yucky stuff that used to be cotton) then the boat isn't any worse off then when you started and it is mostly a matter of opinion whether you used the right stuff or not.

[pipefitter]

I mistook you for someone else or some other post.I thought you had built a glued lap boat and was using caulking to tidy up the joints for paint.I caulked around the trim on the interior of my boat.I use 3M products at work but not when associated with paint. Nor did I know what kind of boat.Sorry for the misinterpretation.

[GC]

No cotton or black yucky stuff at all just some dried out seam compound of some sort. Thanks again for the comments, sorry for the earlier confusion, by the way how many coats of paint is generally required below the water line. I am using interlux anti fouling paint.

[imported_Jimmy]

That depends on a few things like what kind of Interlux bottom paint (they make many kinds), whether the bottom is aready painted or has been stripped down to bare wood, where the boat is, etc. I use Interlux bottomkote xxx and I usually put on 2 coats every year (as per the instructions), although I know some people who only use 1 coat. I suspect in fresh water you could get away with one coat, but it is probably better just to follow the directions. If you have stipped the bottom down to bare wood, you usually put a thinned coat on first.