FWIW.
I have done Ross rounds on the heather and they sold very well but are a fiddel to put together, need a special super, and are costly in parts.
So......... on the KISS principle I used to put some CC inbetween my extracting combs, and on the strong boxes that would be 50% CC.
Buy some CC containers, draw round the outline on a piece of ply, take the out line in by 5mm or so and redraw it, and that is your cutting line. Cut to size, sand, varnish and that is your template for cutting CC.
Tools needed, one knife, one spatula and some newspaper. Oh yes and a very strong colony.... lol
How much more simple can it be?
And how profitable... mine is retailing happily at £9 a pound.
PH