I honestly use Card stock paper. Its a little thicker than regular paper and bends nicely for when I am printing. For the walls I use card board for sets that are just a couple of walls and floor like here.

http://www.joedios.com/dioramas/sho...&imageuser=3885



http://www.joedios.com/dioramas/sho...&imageuser=3885


Foamcore when building a frame a building or house.


http://www.joedios.com/dioramas/sho...&imageuser=3885





http://www.joedios.com/dioramas/sho...&imageuser=3885





I also like hydro call for walls and brick its a light wieght plaster you can make walls and rocks with like.




http://www.joedios.com/dioramas/sho...&imageuser=3885





http://www.joedios.com/dioramas/sho...&imageuser=3885


hope this helps! cheers! DD

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