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  Topic Review (Newest First)
03-26-2012 11:10 AM
maccauley123 I used Dow 739 to bond mine and after two years no problems. If I were to do it again I would try 3M VHB tape. Supposed to be awesome stuff. Found it in a Good Old Boat article.
03-26-2012 10:59 AM
Re: Replacing Leaky Windows

mitiempo, thanks for the article. Great info there.

JanetGroene, great point. I'll be on the lookout. My entire deck is solid fiberglass so I think that will be beneficial to me, but I'm not exactly sure how strong it will be against rot, I imagine more so than woodcore or similar construction. Guess I'll find out.

Another good tip, thanks sailormon.

Love these forums. I'll try to photograph and document the project in a post when I complete it. Hopefully will be able to start and finish before the end of April. Thanks again everyone.
03-25-2012 02:04 PM
Re: Replacing Leaky Windows

I had mine replaced professionally, but was thinking about doing it myself, and found that different types of plastic sheet goods can be bought at a substantial savings on Ebay, and some of them will even cut it for you, if you provide them a template.
03-25-2012 01:43 PM
Re: Replacing Leaky Windows

Don't overlook the fact that water from previous leaks could have channeled long distances within the boat. When you get the old windows out, make sure there isn't rot in unexpected places. Good luck.
03-25-2012 01:40 PM
Re: Replacing Leaky Windows

Here's a link to a comparison between cast acrylic and polycarbonate by Select Plastics, the largest marine hatch restorer in the world. Acrylic -vs- Polycarbonate

Tony knows his business very well and recommends cast acrylic which all major hatch producers also use.

Dow 795 or Sika Flex 295 UV are the adhesives of choice.

Cast acrylic will outlast polycarbonate by a large margin.
03-24-2012 06:02 PM
Re: Replacing Leaky Windows

consider using butyl tape as the gasket. I would also recomend using 4200 for below the waterline. yse I know your portlights are above water but when it is blowing like **** ,raining and the decks are awash it might seem like you are under water. Also, Captain tulleys is also helpful once everything is in place since it helps to seal tiny gaps, if present. We rebedded our portlights about two years ago now and seem to be rock solid.
03-24-2012 02:36 PM
Re: Replacing Leaky Windows

You guys are great ! Thanks, very helpful indeed. I'm happy the tinted acrylic came recommended. Can anyone suggest a supplier, or perhaps a store that might carry it locally, like a Home Depot of sort ?
03-24-2012 11:30 AM
Re: Replacing Leaky Windows

I have done the paint thing...but more recently have spreading a layer of black DC795 to create the same effect and a better seal. Use the darkest acrylic for best effect. However you end up attaching the lens be careful not to overtighten.. Leave a "gasket" layer under the lense.
Good luck - and don't forget to mask everything inside and out to ease cleanup and for clean finished look.
03-24-2012 11:25 AM
Re: Replacing Leaky Windows

LifeSeal is good stuff, but Faster here on SN recommended Dow Corning 795 when I was re-sealing our windows and now I wouldn't use anything else. Fantastic stuff for sealing poly/acrylic to fg.
03-24-2012 10:59 AM
Re: Replacing Leaky Windows

Try this article:


I did it following don Casey's excellent book this old boat. Came out great.

Acrylic is more scratch resistant, but far weaker and only a little cheaper. I used screwed in 1/4 inch acrylic because I couldn't find a local source for lexan, but if I were going offshore 1/2 inch through-bolted lexan would be my choice. Check out don Casey's book it gives the formula for hole spacing and distance from the edges. Just make sure you use a really dull drill bit for the holes, and a jigsaw blade that is meant for plastic, otherwise the stuff will crack. Drill the screw holes oversized to allow for expansion. Do not use silicone, use butyl. It is easier to use and lasts longer. A router with a rounding bit will round the edges just fine, then use 400-800 grit paper to get it shiny (if u even care about the edges being shiny).

My ports had been leaking like sives for years, the po never fixed the problem just put a bucket to catch all the rainwater. So the ply core had delaminates and begun to rot around the edges of the existing ports. I cut away most of the rotten parts, so I wound up with oversized ports.

Use tinted because it looks better and keeps the cabin cooler in the summer. It is easier to hide the cut out as well, because you just paint the acrylic black in all areas except where the ports themselves will be.
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