Which Sealant/Caulk to use??

I've used both. It seems both are good but each have their drawbacks. The 3M 4200 UV is good, but seems to also dry out and crack after a year or two. Better keep the acetone away from the 4200. Deteriorates it pretty bad. The Life Seal is great, but it seems to mildew over time.

I've used them all and prefer the LifeSeal. I also dislike 5200 as it yellows and molds quickly and is a bear to ttake off. It has it's place but not as a caulk line. Stay away from the lifecaulk however as it skins very fast and is hard to get a smooth caulk line with.

I'm a big fan of 4000. Lays down well and doesn't yellow.
Whatever you do, don't use 5200!

+1......go with Sikaflex.

Every boat I've encountered with the black Sikaflex around the windows, always rubbed off on chamois and people's clothes when they rubbed against it. Keep in mind Sea Ray uses a lot of products because they fit in the total budget better than using the absolute best product for the job at a higher price.

5200 or lifeseal. Most are using lifeseal from what i know.

I've always preferred 295UV for caulking, not gueing.

I recently received a free sample of Fixtech. According to the brochure it's way better than everything else (of course). I just sealed the drain of my roof terras with it and will have to wait a year before I can make my mind up. Has anyone used it yet?

Rather than start a new thread, I thought I would try reviving this one. It's been about a year since the last post and much of the original information was very helpful. I am looking for any "new" or updated opinions about which caulk to use. I have a 2000 406 Carver ACMY and am interested in pretty much redoing all of the existing caulk. Everything from the trim on the rubrails to the joints where the bridge connects to the bottom half of the boat.

Essentially:
1. Are there any new opinions on which caulk to use (sounds like LifeSeal was the best)

2. Could anyone elaborate on the "acetone to smooth out the sealant.." I've never done this before but am pretty handy. I just want to make sure I'm doing things as properly as possible.

Thanks in advance to all who take the time to respond.

thanks RC - As I read the thread earlier today, I was hopeing it had multiple pages with banter both ways debateing the merits of one product over another....unfortunately there was great info but no real banter. Judging from you original post your project boat with the SikaFlex should be almost 2.5 yrs old now. I assume it's still holding up well, with no yellowing. (congrats). I appreciate your reply and I will post in this same thread what I ultimately use.

thanks again

Well I just used 3M 4000UV for caulking bridge seams and am very unhappy with the results. I've caulked a ton of flybridges and stuff and the 4000 was like trying to spread mud around and just couldn't get a good caulk line with it. I'm kicking myself for not using lifeseal which I usually have excellent results with.

Most important part is prep work. New Caulk will not stick to the old so when you think you removed all of it go back with adhesive remover and you will find there is still residew there.

Sika products are equal players with 3M and others in the caulking / sealant market, I would not typically consider the use of this product as a down-grade or cost saving measure.

Look for other non-marine sources for black sealant / window glazing, I have had good success with a Dow Corning product. The commercial window glazing market is on a scale way beyond marine............

It was prepped properly. There was zero problems with adhesion, the problem was even if you caulked a foot, you couldn't smooth out the caulk line....it just made it look worse no matter what you did.....wet finger......acetone.....etc..... it was like trying to spread mud around.....

I agree with that. The yacht window guys I've seen don't use "marine" products to seal windows with any more. And they sure don't seem to use them for the frame-less windows on larger yachts.