Hi Martin
Have you thought of a hand held foam cutter, for cutting out the ground work.
I have this one from ebay.
https://www.ebay.co.uk/itm/Electric-Foam-Cutter-Pen-Polystyrene-Hot-Wire-Styrofoam-Cutting-Pen-Tool-/293587163042?_trksid=p2349624.m46890.l49292
Martin Webster
2021-03-14 07:43:10 +0000 UTC
sooo.... not using pigments huh? ;) ended up looking great :)