Help! "Bubbles" forming under styrene plastic streets?

[pnolan48]

. . .
- The styrene that has the bubbles was glued directly to the underlying foam using latex caulk/adhesive.

Latex caulk/adhesive, in my experience, outgasses forever, and that may have weakened the styrene enough. I had sheets of foam that I laminated in 2002 with latex adhesives. They adhesives were still "wet" in the center of larger sections when I pulled the layout apart in late 2010.

[nkalanaga]

Pete:  I noticed that.  Fortunately I nailed my sheets together as well, with 8 penny nails, so just left the nails in. 

Why nail foam sheets together?  It'd easier than trying to clamp them while the glue dries, nails are cheaper than clamps, and they push in easily without tools.  If one is in the way of later scenery, just pull it out and put it somewhere else.

[Bart1701]

UPDATE: The street crew arrived and has pulled up about 18" of the bubbling street, and a couple of bubbling parking lots along the way. I now have exposed pink insulation board -which does have some nicks and dents in it that will need to be attended to.

In looking at my situation, I would be able to use the following approach:
- Fix the occasional nicks and dents in the foam using plaster or sculptamold.
- Secure cork roadbed sheets on the foam where the streets and parking lots would be - using Loctite Power Grab to secure the cork to the insulation foam board. Also would use rubbing alcohol to to clean the surfaces before gluing these together.
- Secure .030" styrene streets and parking lots to the cork using Loctite Power Grab to secure them. Also would use rubbing alcohol to to clean the surfaces before gluing these together.

The .030" street would be butting up at each end to existing sections of .010" styrene streets that have not encountered any bubbles. These areas had plaster or sculptamold under them - so I think the adhesive caulk is holding well for me (it's been over a year without any bubbles forming). Since these butting areas are where the  .010" road was on a hill that was either starting or ending, I think I should be able to account for the thickness of the cork and .030" stryene by making some adjustments to the elevations at these points so that the roads remain smooth at the seams.

How does this sound? Do you think it will work or will I have issues with bubbles again at some point. I am thinking the that cork (which is a porous surface, isn't it?) would help the adhesive properly secure everything?

Thanks,
Bart