Re: Coaxial Wedge Collaboration
I suspect this is because the grill you chose has a LOT of open area compared to some of the grills I most often see. This leaves you with much less grill surface area for the foam to bind to. You can try re-spraying or gluing, but I have a feeling that this may be an ongoing problem if the wedge gets used a lot. In hindsight I would suggest a less porous grill or putting the foam on the outside.
Of course that's not helpful now.... all I might suggest now would be:
-re spray on an as-needed basis
-glue (choose carefully as some glues will eat the foam)
-try a slightly denser but thinner foam product which may give you marginally better contact with the grill with possibly less weight if made extra thin
-try to devise a couple of support rods behind the foam to keep it pressed to the grill
