I'm starting to design as I go. I got a 5' 2000# axle from TSC to replace the axle on my 4x8 NuWay folding trailer. I will move the spring seats in slightly and widen my frame so I can get 15" tires on and have more than 1" of clearance between tire and wall. I may decide to add brakes at some point--does anyone know if I need additional clearance between spring seat and hub face or will brake drums fit if the backing plate is welded right at the end of the axle tube?
I made a 4x4x8 model out of cardboard (the smaller one in the photo below: 1/2" = 1'). Then I made a model out of scrap hardboard and duct tape with ~5x5x10 floor (~11.5' including front and rear curves which I shaped until we liked it; 1"=1').
There are a few more pictures in my album, but here are 2 of them
and
joe