Lee Valley Tools publishes the story of Marco Facciola, who built a bicycle out of wood and glue and absolutely no metal parts.
"I wasn't sure my wooden bicycle would actually work. I quickly realized the first pieces of the puzzle I needed to figure out were the chain and the sprockets (gears), since the design of all the other components depended on these."
"When I look back at the completed project, I realize that building the chain caused the most problems and also took the most time (nearly 40%). One of the biggest difficulties was drilling a hole in the spacers—the hollowed-out, cylindrical pieces of wood that keep the two plates apart."
And no easy-to-build fixie was good enough for Marco, "I decided to add a ratcheting system to the bicycle. This would allow me to ride down a hill without having to pedal. If it was a direct-drive bicycle, I would have to pedal at all times."