VIC
871 posts
Anybody know the current thinking on bonding in bridgedeck windows?
I'm going to need to fit 2 in the next boat, and since we are starting with a blank canvas as such, I thought it best to do a bit of research and ask the brains trust.
The aim is for a sleek, flush look, without screws, and by windows we are talking tinted acylic, like what you see on virtually any modern cat.
Problems I have found in the past is the heating and expansion of the window material, beyond what the sealant can handle. Add to this a few curves, and you are pushing the friendship
I have in the past tried scuffing the edges of the perspex, as well as using the etching/cleaning fluid first. Bedding was done with the recommended Sikaflex with UV protection, but still in the end it has tended to break the adhesion with the windows material.
I read somewhere one way was to rely more on special double sided to bond the window, and just sealant on around the lip to create a smaller bead seal.
Anyone have any success stories?
NSW
397 posts
Hi Crusty
I recently redone my windows and went from bolted on to glazed on and it really improves the whole look of the boat.
I used The fixtech system (FS200).
Pm me if youd like more details over the phone.
VIC
871 posts
Thanks for the tip Hangetime,
I'll look it up and get back to you.
Glad it gave you the results.
NSW
331 posts
I had read that 3M brand double-sided tape VHB 4991 is known to be very good for bolt-less window installations. It comes as a roll ½ inch wide by 100 feet (33metres) long and 2.3 mm thick.
No through-holes that can leak; the panel just sits on the outside held by the tape. The tape is expensive but it has to be to endure UV exposure for five years plus.
I bought some and used it with no problem so far. My acrylic panels are about 500mm long and they feel very firmly held by this tape, plus, exactly as you say, a bit of sealant (not adhesive) to fill in the trough between the panel edge and the yacht surface.
VIC
871 posts
karsten where did you source the tape,from your acrylic supplier?
Did you still end up spraying a black edge internally to protect the tape being UV exposed?
Apparently bumper bar touch up paint can be used for this, but then I would have thought you'd be relying on how good this bonds to the acrylic for your seal.
NSW
331 posts
Crustysailor, I bought mine in Sydney from Wayne Richards Sales (WRS) 9674-2033. They were one of three Sydney companies that stocked it.
You could always contact 3M Australia and ask who retails it in your area.
Since adhesion is so crucial, I carefully cleaned the acrylic panels before installation and chose to stick the tape directly to the acrylic rather than risk introducing another layer (eg. paint). I expect that the acrylic itself provides some UV protection. Twelve months and it looks fine so far.
