Here are some pics of a bridge I built over the weekend. It will be used to span across a doorway so it can be removed and stored. The overall length is almost 4 feet, and it has no supports in the middle. I used a piece of "unistrut" which is a piece of steel channel 7/8 inch deep and 1-1/8 inch wide. I used three Atlas girder bridges, the floor sections out of 2 Atlas truss bridges, a Walthers singletrack truss bridge, and various sizes of strip styrene and T-sections. The bridge will fit into some groves at each side. I scratchbuilt the girder sections underneath the Girder bridges, the truss attachments under the unistrut channel, and pieces here and there to make it look complete. Then the entire thing got a coat of flat black paint, then weathering with burnt umber and raw sienna for rust, some gray for dust and fading, then drybrushed the whole thing to bring out the details and edges.