VHB adhesive for Acrylic windows?

[TJM]

My 40 yr old Trawler had leaking windows (of course they do) along the walkways. I removed the entire frame and I am replacing the sliding glass window with a tinted acrylic solid piece.
For ease of install I will be using the 3M brand VHB tape and then caulking the outside. The double sided tape will be applied to the painted fiberglass on the outside face and the acrylic window layed over it. The acrylic is 3/4 larger on all sides and will be surface mounted. My question is what adhesive to use? Has anybody used this technique before? All of the new boats are moving to this "frameless" method.
VHB = Very High Bond

 

[Bmarler]

Using a tape for adhesive like that will require the surface of the boat to be nearly perfect. No defects or waviness or there will be gaps in the adhesive that will leak when the exterior caulking develops a crack.
There are many thicknesses of the vhb tape, some with foam to let you adhere to substrate with slight variations.
There would also be butyl tapes you could use, or also consider the 3m automotive urethane for windshields. That requires the adhesive to be protected from uv exposure.

 

[tiltrider1]

I temporarily (10 years) replaced a curved window with a piece made out of acrylic. The first thing you need to understand is that acrylic will expand and shrink a lot. This means any method of fastening needs to be flexible.

I used 3M 4000 UV and screwed the acrylic to the boat. It ended up looking very good and thE seal was never breached. It worked so well that 10 years went by before I got around to replacing all of the boat’s windows.

The key to making it look good was to paint the inside border of the acrylic 2” in my case to hide the sealant from view.