As far as I can tell, the largest strips that are available from Evergreen and Plastruct are 1/4" square. Does anyone know of a source for styrene strips in larger sizes than this?
Plastruct does have ABS square and rectangular tubing in larger sizes, so that could be used if all else fails, you’d just have to fill the ends to make it look solid.
You guys that build styrene boxcars and such, what do you use for the sills and end beams?