Construction bricks

thingiverse

Not overly related to the original, but I took this model (which printed super well) and chopped off the wheel mounts, and then made a bunch of variations of the brick based on different walls and heights. You can open this file in your favourite editor (I use TinkerCAD) and copy/combine different parts to get whatever brick you're looking for. Note that the final dimensions of a brick are 32mm x 32mm x 9.6mm (plate) or 19.2mm (brick) excluding top studs, with a clearance of 0.1mm on any side with a wall. E.g. a 2x2 brick should be (32 - 2x0.1) x (32 - 2x0.1) = 31.8mm x 31.8mm whereas a 2x4 brick should be (32 - 2x0.1) x (64 - 2x0.1) = 31.8mm x 63.8mm. I'll warn, though, that the 1x2 brick is VERY snug and actually slightly damaged my real duplo, so you might want to slim down the inner walls. Other bricks don't seem to have this problem however.