We are using plastic sterile brand containers bought at walmart. they wont stick to the foam and come in many different general sizes and shapes. Using these is easy and very cost effective for making custom sized foam chambers.
Tony,
Thats a possibilty. But it may very well hinder getting to the bow even more putting one on each side. Once we get this one put together we will take a look at this possibility.
I saw that and could see what you were using for a mold. A saw cut could be made thru the length of the cast foam block once it is removed from the container. This of course would result in two wedge shaped foam blocks. A carpenters hand saw (non electric) would make short work of this.