How many of us have gotten the canned spray foam somewhere it shouldn't have been & had it cure there? Tenacious stuff isn't it? The thought has occurred to me to take advantage of that property to make composite panels. In fact, we built our house from Structural Insulating Panels made just that way, except that the skins are OSB. The bottom skin is laid in a form, liquid polyurethane foam is metered out of a spray bar onto the OSB, the top skin follows the spray bar, & then a top frame is locked down over that to contain the pressure of the expanding foam. No adhesives - the foam self-adheres to the skins. Pretty simple process. This particular facility is set up to make panels up to 8' x 24'.
Aside from some trial & error to get the volume metered correctly for the intended panel thickness, can anyone think of a reason this technology could not be used to form FRP-skinned composite panels? One thought is whether the waterproof nature of the FRP would inhibit the foam cure, whereas the permeability of the OSB allows gasses to escape? I'm planning some small-scale testing once it warms up here (from the 4 degrees F we have this morning), but larger panel sizes may manifest issues that do not occur in a small sample piece.
The foam distribution technology could be borrowed from the spray foam industry, with multiple spray heads off a manifold bar on tracks replacing the single hand-held nozzle the guy uses in your attic. The form would be a simple aluminum or steel framework. Engineering calcs would provide sizing for the form framework to contain the pressure of the expanding foam.
Maybe this falls in that black hole where it's too much for the backyard, DIY guy to take on as a proof-of-concept, but not enough potential return for commercial technology to invest in the necessary startup development? Any thoughts?
Aside from some trial & error to get the volume metered correctly for the intended panel thickness, can anyone think of a reason this technology could not be used to form FRP-skinned composite panels? One thought is whether the waterproof nature of the FRP would inhibit the foam cure, whereas the permeability of the OSB allows gasses to escape? I'm planning some small-scale testing once it warms up here (from the 4 degrees F we have this morning), but larger panel sizes may manifest issues that do not occur in a small sample piece.
The foam distribution technology could be borrowed from the spray foam industry, with multiple spray heads off a manifold bar on tracks replacing the single hand-held nozzle the guy uses in your attic. The form would be a simple aluminum or steel framework. Engineering calcs would provide sizing for the form framework to contain the pressure of the expanding foam.
Maybe this falls in that black hole where it's too much for the backyard, DIY guy to take on as a proof-of-concept, but not enough potential return for commercial technology to invest in the necessary startup development? Any thoughts?
