Storminator
First Post
Shaping? Why would you want to shape it on a trash can? Do you mean cut it?
If you're shaving off small pieces of foam, it's better to let that fall in a trash can instead of your table or floor. Otherwise you'll be finding tiny pieces of foam for months...
Why seal? Do you have to cover the whole thing?
Most spray paint will dissolve styrofoam. Coating it with glue prevents that. Tho you can get some interesting ruins my spraying your foam buildings...

PS