Looking at my last 9mm insert, there is only 4 walls on the bed....a space between the two inside walls and the two outside walls.
I'm wondering if the hole between the inside layers and the outside layers would fill in if 3 walls were chosen instead of two? What's your experience TylerR? On this part even one wall might help, I'm thinking. But one thing is for sure, even with 2 walls, mine has never fallen over, requiring a decent bump with the Chisel, as I already described, to break it loose. NO RAFT either.
https://i.postimg.cc/4NF7jGRW/IMG-3949.jpg
There!, TylerR......now can you see some imperfections with this close up? ;)