This 3D model was originally created with Sketchup 8 and then converted to all other 3D formats. Native format is .skp 3dsmax scene is 3ds Max 2016 version, rendered with Vray 3.00 Realistic Rail Track ... Extend Straight Rails and add as many sleepers as you want... Curves are Pre-Set... Just Copy %26 Paste them together...they are all in the components... Size of model... less than 1 mb.. Note: There will be Cross overs %26 Points... if anyone downloads...