Windows leaking, 41 DS

[Dockhand]

Looking for anyone that has re-bedded the windows on a Deck Salon, I have done Windows on Hunter built in the 80's. What I understand is the Windows are Acrylic and Hunter used Dow Corning 795, like Sika 521 to bed them at the factory, which is a Silicone material. Hunter today has Acrylic Windows and uses Sika 295 which is a Polycarbonate material.
Question:
Is this what is being used in the after market and what problems may I have re-bedding these larger Windows?

[doublebubble]

G'day Dockhand, been or had been through this issue lately with our 50ft cat, we have replaced all our windows, 20 plus of them, and ran into the same problem, the windows are acrylic and I did use Sika 295 which just doesn't seem to adhere to acrylic very well at all, there was an external bead of 295 around the outside which I could see was just coming away from the acrylic, well that didn't work, six months later leaks appeared, the only sealant to use on acrylic windows is Dow corning 791.

Regards Rod.

[Bill O]

We used Dow 795 ~9 years ago to seal acrylic into the teak skylight and 2 other teak hatches and it still remains tight. Great stuff.

From the Dow 795 product sheet:
Weather sealing of most common construction materials including glass,aluminum, steel, painted metal, EIFS, granite and other stone, concrete, brick and plastics.

Here is a list of compatible (and non compatible) sealants for polycarbonate. Dow 795 is listed as compatible. https://www.palramamericas.com/docs/..._1_13_2015.pdf


Bill O.

[doublebubble]

791 was only used as a recommendation from a company named City Plastics whom were the people that cut out and supplied our new windows, Marga Cipta Acrylic, so far all good, ablit only twelve months, so fingers crossed.

Regards Rod.

[SaltyMetals]

On some versions of the Jeanneau 43 DS the saloon windows would start leaking because the box at the foot of the SS support post for the mast positioned on the keel was settling. Hence the mast and deck was settling as well, thereby distorting the fit of the windows. A costly repair. Not sure about the 41 ds.

Have you already tried Captain Tolley's Creeping Crack Cure? Absolute magic and saves a lot of time and expense.
Andrew
"Genial Bee"

[Dockhand]

When I talked to David at Hunter he was a great guy, but when I talked to their tech it's hard to know. When the tech at the New Hunter company tells me this is what they use today (Sika 295), I believe it. And what they thought the old Hunter used (Dow Corning 795), he should know. On my last boat I did them once and it lasted 17 years, so I would think I should get a least 10 after re-doing them.
Thanks, I'll look at the data sheet, anyone else has any info that will help me please post it or pm me.

[Cpt Mark]

I contacted Island Packet for a specific recommendation as they use acrylic for the windows. They said to use Silpruf scs2000 which is a GE product. It is industrial silicone. Think high rise windows bedded in and no fasteners.

Silicone. If yours were bedded with silicone before NOTHING will stick to it besides silicone. You cannot ever get silicone completely off. I bought this at an industrial adhesives store for $7 a tube.

[fworonkowicz]

after years of leaking windows and hatches on C&C 38 Landfall I used the silicone GE SILPRUF 2000 and since 7 years sailing on Chesapeake Bay and Florida no problem. Surfaces clean using rubbing alcohol. The exsensibility of Silpruf 2000 is +/- 50% and this adhesive silicon work well with acrilic . I buy usual on intrenet.

[ranger58sb]

For a quick and probably temporary fix, you might try a bead of clear Flex-Seal (as seen on TV) around the lenses. Some of us have used that as a useful stopgap (so to speak)...

-Chris

[Akapeterc]

I had a Shipwright re-bed two of my front facing windows in my deck saloon and when they replaced them they cracked I was then told by a glazier that once they are taken out that should been replaced as they will always crack with putting new pressure on them Sorry can’t help you with what they used to sell them but they don’t leak now