hi all
........I'm in the U.K.and for all those over this side of the pond ,i think /suspect that SINTRA is the same as FOAMEX ,this is stuff a friend of mine in the graphics and sign industry here uses ,it is the white [any colour you want]back board he applies vinyl cut lettering to........i've mucked around with the stuff and it seems the same as people are talking about here ,can be heat bent easily etc........also BONDO over here is just epoxy [2 part]car body filler ,...in england there are various brands /types P 38 from halfords ...P40 is a resin/fiberglass paste ...there are cheaper makes too ...
an often overlooked material that is light ,needs no catalyst ,bonds incredibly to styrene is PLASTIC WOOD ,a cellulouse based wood filler that will not crack off when dry ,can be sanded or used as a base for a finishing filler like p38 or other modelling/plumbing putty ....use all of these fillers in ventillated spaces........or 3 years from now you'll wake up one day and find youre living with a battledroid ....like i did 