diy rcp tracks

[aero528]

i have an idea, tell me if you like it or not. if you were to take foam that you get from the hardware store(the kind that is like the mats that come in these track, if you know exactly what kind tell us) and you cut out different shapes for the curves and strates and such, but then used the extra material(or more mats) to make the walls wouldent that solve the problem of haveing pvc pipes hurt your car? is that the same as what rcp track walls are? also you might be able to get the texture of these mats the same as those in rcp trackes by useing different grade sand paper. i have never seen one of these tracks in my life, but would like to see a cheaper version that works the same.