Sealant type

[seacolt]

What type of sealant should I use to bed my fixed window frames to recently painted awlgrip. I don't want to do this a third time.
Thanks

 

[yachtsmanbill]

4200 or 5200 UV from 3M it wont yellow from the sunlight..., if that matters! ws
http://www.boatbuilding.net/article.pl?sid=08/09/22/1259202&mode=thread

 

[spartonboat1]

4200 or 5200 UV from 3M it wont yellow from the sunlight..., if that matters! ws
http://www.boatbuilding.net/article.pl?sid=08/09/22/1259202&mode=thread

Hey YB, wouldn't that be 4200 Ja, 5200 Nine? I thought the 5200 was for "below the waterline" and would not come apart in the future without damaging the part? My belief anyway...

 

[Maynard Rupp]

5200 won't come apart above or below the water line. I would not use 5200. 4200 will do the job very well. You should not have any external caulk on those frames but if you do want a bead on the outer edge it must be 3M #4000. That is the only 3M stuff that is UV proof. Don't forget to pump lots of caulk in each screw hole before you install the screw. Most leaks I have seen were from the water coming in around the screw. Just shove the nose of the caulk tube in the hole and squeeze a good amount out before installing a screw in that hole.

 

[Vincentc]

If the screw holes penetrate into a balsa core, I would not rely on sealant alone but would replace the balsa in the area of the screw holes with filled epoxy. Removing my window frames was a lesson in how well balsa can absorb water.
Vincent
43 DC Lilly Marie

 

[REBrueckner]

For the past 30 years I would have highly recommended white LIFECAULK, but after using some a few years ago...no more...it ended up cracking!!!!...

I spoke to an old time professional carpenter doing woodwork on a nearby sailboat a few weeks ago and he had the same experience....trouble with white Lifecaulk....
the black is the stuff so commonly used beween teak deck planks that seems to last forever. Maybe the white was a batch problem from the manufacturer, but I would not take any chances.

There are now 25 year and 50 year caulks for $2 or $3 a tube at Home Cheapo....I have used them several times for small jobs, as well as around the house, so far, so good....NEVER USE SILICONE CAULK...it's awful to clean if recaulk is needed and nothing sticks to it; it cannot be painted....

 

[Paul45c]

I'd second the use of 4200...you could also use Sikaflex or 101. They're both paintable and clean up easily, yet durable and not impossible to pry apart years from now when they'll need to be rebedded again.

 

[Walter P]

With all due respect Rob, I would be a bit wary of Home Cheapo caulking material on a boat. While they are probably fine for home or other land uses, on a boat they may fail. Boats develop leaks around all fittings eventually no matter how good the caulk because they are constantly moving and twisting. Even a solid boat like a Hatteras is subject to stresses which over time will cause caulked seams to fail. I would stick with products specifically developed for use on boats or else research the proposed HD product thoroughly before investing all that labor in vain.

Walt

 

[Jimmy Watts]

There is another product that I have found to work extremely good. UV-4000.
3m product especially designed to withstand uv rays. Its a little below 4200 as far as strength is concerned, but if the surfaces to be caulked are prepared correctly, strength is not that great of an issue especially since screws are going back in. UV-4000 stays fairly plyable with time.

Jimmy

 

[Banshee36]

I would also use TEF-GEL on the screw heads, it cuts the inevitale bubbling of paint at the the holes in the frame.
JW

 

[REBrueckner]

"...Boats develop leaks around all fittings eventually no matter how good the caulk because they are constantly moving and twisting...."

much less so if the caulk remains flexible...thats the most important criteria....and what do you think moves more: fiberglass or wood on wood in a home which absorbs moisture,dries, and also expands/contracts?????

"marine caulk" is a meaningless term except perhaps in underwater applications....I used white lifecaulk white to repair a crack in my swimming pool skimmer about ten years ago...that caulk is still soft, pliable, and in place....

I used some two dollar Home Cheapo "50 year caulk" about ten years ago and it is still pliable and just fine....