Salon Window caulking, sealing and maint.

[Sonosailor]

Fer sure this is a cat issue, but it may be only boats like mine. I have an FP 35, 1996 (Tobago). The black goop used to install and seal the large, curved plexiglass windows leaves terrible black streaks down the windows and over the deck. It is most noticeable after a rough passage, when salt water has gone under the sun-shade. It can get worse if you use cleaners near it. Has anyone found a product to seal it off or stop the deterioration? I'm hoping someone has used a caulk or wax product that can slow this down.

[schoonerdog]

that would be a second for me. What I did do was reseal a window with a better product called super silicon. It has far better UV resistance than the sikaflex that is typically used. If someone does know of something that can seal in the sikaflex I'd be interested as well as I have several more windows that I'd prefer not to reseal.

[cabo_sailor]

A heavy rain just passed through and all the odd gods know we can use the water BUT it also physically reminded me that a couple of my ports need attention. (Why did it have to drip on the instant oatmeal?).

Oh well, on my list and when I get to it I plan on using butyl nitrate tape as a sealant. I've used it on one port and it seems to be working just fine. A friend who used to be in the telephone repair business swears by the stuff. Of course, he does tend to swear quite a bit about everything!!

Personally, I'm starting to agree with the camp that silicone is not the thing for boats. We'll see. I must admit a 50 foot roll of the tape for $5 from a motorhome website makes it an attractive option.

Rich

[Christian Van H]

You are right on, Cabo! As long as the windows are mechanically fastened, Butyl ROCKS!!!

[mikereed100]

Originally Posted by Christian Van H

You are right on, Cabo! As long as the windows are mechanically fastened, Butyl ROCKS!!!

I used this stuff to seal an a/c unit on top of my motorhome. It was a crappy motorhome so the roof sagged, which meant that the a/c unit lived in a small lake of it's own making for month's at a time. Never leaked a drop. When the a/c died it was real easy to remove it (try that with sikaflex) and there was no sign of water intrusion. I always wondered why I didn't use it on my boat. I plan to use it to seal all of my hatches on the new boat.

Mike

[Christian Van H]

Hey Mike! New Found Metals recommends Butyl cord caulking for all their porthole installations. One secret of installation is to keep the tape / cord cool until you apply it. If this stuff gets hot, GOD HELP YOU! You'll pull tiny little black strings all over your nice gelcoat, curse like a sailor, and just for fun you should roll around in some feathers too!

I'm going to start a new thread, asking whether Butyl caulk makes a good sealant for diesel tank access ports...I think this stuff is great!

[schoonerdog]

The butyl tape and cord sound like a great idea, a couple questions, and thank you for th response!

how should it be applied and can it be used to seal existing window or hatch without removal?

I think the original question was whether it could be put on top of the sikaflex that was breaking down. Which type and where would we get it?

[GordMay]

Butyl glazing tapes temporarily adhere to surfaces, by means of their inherent tack, but for proper long-term performance, they must generally be compressed between surfaces. Think gasket.

[mikereed100]

As Schoonerdog points out, Sonosailor's original question remains, how to stop deterioration of the existing caulk? Assuming there are no leaks I wonder if it could just be given a coat of paint? This also begs the question, what is the best uv resistant caulking for windows?

Mike

[cabo_sailor]

For my installation I will be removing the exterior rings which are sealed with silicone. To facillate the removal I will be using a product called "Debond". The stuff is amazing. It almost seems to turn silicone, life caulk, or 5200 brittle. Makes it very easy to remove.

The butyl tape I'm using is not black but grey. It comes in a ribbon about 1 in wide and roughly 1/8 in thick. I got it online from a motor home supply company. Fifty feet was about $5. In the past I've used the windshield sealant for cars but it was black, goopy, and a bit too thick to my mind. Plus it was much more expensive.

As to stopping deterioration of existing caulk, I personally don't believe you can. You might get lucky and slow it down a bit or even stop leaks for a little bit but they will return. Remember the old adage "If you don't have time to do it right, when will you find the time to do it over?"

As to UV, since this is the stuff used on cars for windshields I suspect, with no data, that it will be just fine. I've read articles in Good Old Boat of people using this to bed deck fittings in. Many years later, no leaks and the material is still flexible. Because of this, I don't think you should even consider having paint adhere to it long term.

Hope this helps,
Rich

[SurfNRG]

Sorry, but don't have an answer to how to deal with your already existing sealant but I did just replaced all my windows on my Wildcat 350 and am very happy with Boatlife's Life Seal (not Life Chaulk). It has UV protection and everyone I've spoken to that have used this product is extremely happy with it. Life Seal is compatible with polycarbonates like Lexan or Macralon which is what I used. I assume it would work equally as well with Acrylic. Abrade the surface to help adhesion. A technique I used to keep the "goop" from overflowing to the inside upon the application was running a closed cell weather stripping tape (Ace Hardware) along the edge of the frame where I installed the windows. The outer seal was also with Life Seal and has not bled as yet and I'm not expecting to do so (knock on fiberglass). I used a couple mechanical fasters (screws with larger washers) in the areas that had an extreme curve. I learned the hard way that it's best NOT to drill through the polycarb (thermal expansion will get you) but instead drill between the two panes and use the washer to hold the windows in place. Of course, the panels are also held in with the Life Seal. I would also coat the back of the washer with Life Seal so you have a cushion between the stainless washer and polycarb. Kind of went off from a solution to your problem but if you need to replace or re-install I would certainly go with Boatlife's Life Seal. Great product! Here's a few pics of the install. PM for other pics if interested.

[Hatchmasters]

Sealing acrylic to aluminum, stainless and fiberglass is my life's calling. Do yourself a favor. Use either Sika flex 295 UV with primer or Dow 795. The builders use it, the yards use it, I use it, and you should try it.

Do what makes you happy, but if you want a leak proof, flexible and UV stabilized seal consider the two products above.

I use 795.

I haven't used the black death (butyl) for 10 years. Look into UV stabilized double stick foam tape.

Tony "Hatchmasters" D'Andrea

[delmarrey]

For my windows I used Butyl tape to seal it against the backing and then put Boat-Life sealer over that to seal in any runniness (is that a word?) when it gets hot.

[schoonerdog]

I've heard from several sources, builders of my St Francis for instance and other boat builders that the Sikaflex 295 black actually is NOT UV stable. In fact, I pretty sure that is what was used to install our present windows and is causing the black weeping now. I've heard that the Silpruf SCS 2000 is UV stable and doesn't leak.

[Sonosailor]

Okay, I'll buy that there is little that can be done to stop the dirty black marks coming from my existing sealant. So... can I hear from anybody who has successfully removed the large acrylic windows from an FP or similar cat for reinstallation?

I've tried to dig out the calking from a 2 sq.ft. window facing the cockpit, so I might use the space for an air conditioner while on the hard in Trinidad, and after a day of trying, I actually gave up!!

Ideas? I'm willing to listen to those who have not yet done it, if they have an innovative idea to try. I'm thinking of some wonderful disk that sits on a drill or dremmel, that digs that black gook without scarring the wondow or the fibreglass. Does something like that exist?