3M 4000 UV polyether caulk sucks!

[Keith]

This is what 3M recommends for outdoor use. It's white, supposedly resistant to sunlight, etc. I put some on about 3 years ago. Today, a lot of it is gone, the rest is rubbery in some places, powdery in some places, and gooey / sticky in some places. What a mess! The sticky stuff reminds me of uncured polysulfide. Took solvent to get it off the boat, tools, and myself.
*

*
OK, so that doesn't work and I haven't had much luck with Lifecaulk polysulfide either. I need something to caulk joints between teak and fiberglass, outside, preferably white but teak colored would work too that will hold up in sunlight. Any suggestions?


-- Edited by Keith on Wednesday 1st of April 2009 03:54:57 PM

 

[Baker]

Check Your choice of font. I am likely one of the youngest dudes on here and I can barely read that....

 

[Marin]

We've used 3M 5200 for a few "temporary" repairs to hairline gelcoat cracks and so forth and then found it easy to keep putting the permanent repair off. Some of these are in full view of the sky and weather and are some eight years old. The 5200 has yellowed just a bit but it has physically held up just fine. Of course this is a different climate that what you have in Texas so I don't know if the exposed 5200 would hold up as well for as long down there. You can paint over cured 5200 which would undoubtably improve its resistance to UV and the weather.

The most effective deck calking for teak decks is TDS (Teak Decking Systems). It's a one-part caulk and is so good Grand Banks is now using it to calk the deck plank seams in their boats at the factory. We've used it to reseam sections of our deck and it's holding up great. In these applications the color used is always black. I don't know if TDS is available in white.

One thing to consider is that some caulks are damaged over time by the application of certain cleaners.* I have never used 3M 4000 so don't know what might affect it.* But even deck seams like TDS can deteriorate if an owner uses an incompatible cleaner on the deck.* Is it possible you've been cleaning your boat with something that's been attacking the 4000?

-- Edited by Marin on Wednesday 1st of April 2009 06:04:16 PM

 

[FF]

Accept reality , boats need work , bedding or re bedding is part of the deal.

We use Dolphinite under any item that is flat enough to use it , as it cleans up in moments for the re bed .

Many new items have a good enough flange to use ribbon calk, this is sold in rolls , of various widths and thicknesses.

Really EZ to remove and replace.

5200 is a glue not a calk.

FF

 

[Keith]

This is a caulking job, not bedding. It's between a teak door frame and the fiberglass. Frankly, I think it might have been a poorly mixed batch of caulk. The white pigment was probably titanium dioxide. Since the caulk was just gone in places, powdery in others, flexible in others and also sticky in places, it acted like a batch that wasn't completely mixed. Who knows? At least it was fairly easy to get off, although I had to wear latex gloves and use Goof-Off to remove the sticky residue from everything.

I got several votes for Lifeseal, which seems to be a polyurethane / sillicone combination. Also some suggestions for various Sika products; I'll look at the latter when I head to the store today to see what they have, but will probably go with the Lifeseal, since I know it's readily available pretty much everywhere.

 

[Phil Fill]

4200 or 4000 does not have a good adhesion/holding as it is for bedding under pressure between two surfaces so they can be taken apart easily.* Calking was/is for sealing/filling between to surfaces.* However, some of to days calking have super adhesion like 5200,but then people complain it sticks to well?* I use 4000/4200 bedding deck railing fixture, and 10+ years ago used it to reinstall the bow thruster, which is still in good shape, but its between 2 metal faces and under pressure.


*
Furthermore, 4000, 4200 and even 5200 will not stand up to teal oils/dressings. Calking specially made for teak decks will hold up.* I for15+ years have used BoatLife-teak deck calking on the Teak decks and very satisfied.


*
I use 5200 to sell along rub rails windows things that require good adhesion with out pressure. Every year I have to take out and reply the 5200 in certain areas.* So like FF said calking require correct application and maintenance.**

 

[Nomad Willy]

I use Sekaflex 291 on almost everything and over the years come to trust it. I use it in place of 5200 for the usual reason. When I really need the high performance I do use 5200. Last summer I needed to caluk some hardware on the cabin top with the obviuous exposure to UV so I used 3M4000. Didn't even last into mid-winter* ..* leaks, peeling and mechanical breakdown. I have some wonderful HD tape so I pulled off the 4000 and taped over* ..* been dry since. We're quite serious about preping for paint or gluing/bedding/caulking so I don't think that was an issue but Murphy does follow me around.

*** Eric Henning