This Instructable covers a basic version of this. For details on how I got my steampunk look go to www.buildlog.net
Anyway this is my entry to the Epilog Laser Engraver Challenge. Vote for me and I will share it with local Chicago makers, builders and hackers.
Step 2: Build Pedal Shafts
(2) Galvanized 1/2" pipe flanges
(2) 1/2" black pipe pieces 8" long
(4) 1/2" black pipe elbows
(2) 1/2" x 3.5" pipe for the offset pieces
(1) 1/2" x 3.5" pipe for the center section.
Build this first to get all the measurements needed for the other parts. Put all the part together as shown in the picture. Tighten them very tight, but make sure everything is squared up and the bolt patterns of the flanges are square. I primarily used black pipe parts because I found some around. To prevent the parts from loosening later, I tack welded them, but I am sure epoxy or JB Weld would do. Measure the offset the pedal shafts have from the center. This will be used for the bolt patterns on the wheels later. Measure the width of the clear areas of the pipes in the pedal area for the widths of the pedals.