1 Sheet 2'x4' 1/2" MDF
1 Box 1" 1/4-20 Set Screws
1 Box 1/4-20 Lock Nuts
I'm using a CNC with a 25"x25" table, thus the 2 2'x2' sheets.
Wooden train tracks, compatible with most commercial tracks and toy trains. Cut from 1/2" MDF. Create toolpaths from the attached DXF files. Cut the profile 1/2" deep, and cut center on the track line 1/8" deep, all using a 1/4" endmill.
Connectors can be made from MDF (might break, but I have some drawn in anyways) or from common hardware. I used 1" 1/4-20 set screws with lock nuts which slide in perfectly and hold them as securely as other systems do. Those with 3D printers may want to try: http://www.thingiverse.com/thing:15165
Careful when cutting using MDF, the ridges can rip easily on the CNC, but they seem to be standing up to normal play.