Of course, I carefully read your message Bracing with regard to bracing the long panels with expansion foam; now I'd like to know how you do this exactly. Filling in the foam seems to be a 'dangerous' job, because you don't see what really happens inside the cabinet.

I would leave the cabinet open at the back and fill 3/4 of the cavities with the foam to preload the horn slopes, side panels, top and bottom panels.

After that I would assemble the back panel and drill the holes to fill the remaining 1/4 of the cavities. To my mind this reduces the risk of cracking the cabinet.

What do you think of this? Thanks for your assistance.

Harald