I am looking for something to seal the windows with. Being 7 feet long, they are going to expand and contract with temperature. From what I can determine, we are looking at 1/4"- about 1/8" either direction at the ends, where the expansion and contraction is greatest. I was turned on to "Big Stretch" as a possibility, and I wanted to test it to see.
It claimed a two week setup time, so I made this test piece....
Had I-gor sand it well...
And set up this testing scheme, letting it dry for a month.
I put this goal, 1/4" of one-direction movement, which is twice what it should theoretically have to endure. I put a nut on that little black carriage bolt and started cranking....
The pressure was too much for a little hole in 1/8" acrylic. New approach.
Now we are pushing rather than pulling. You can see the new goal drawn on the plywood.
Here at almost 1/4" past the goal, it looks stressed, but not coming loose.
Another 1/8" and it finally ruptured.
You can see here that it stuck very well to the wood, but not as well to the super-slick acrylic. It could bear some roughing-up with some 220-grit, perhaps.
All-in-all, I'm optimistic about using this product on the windows.