Tuesday, August 19, 2008

Master craftsman

Marco Facciola, a 16-year-old high school student, constructed this bicycle completely out of wood.My artist son-in-law sent me a link to an article about Marco Facciola, a 16-year-old high school student who built a working bicycle--including, most significantly, a free-wheeling gear-and-chain drive system--completely out of wood.


"This project came to mind as I was reflecting on the many stories my opa, Case Vandersluis, told me about his adventures in Holland during World War II," Facciola writes. "Opa was roughly the age I am now when he had to build wooden wheels for his bicycle, as rubber was scarce during the war."

People who only saw a brief summary of the original story made rather disparaging remarks about the entire project, some of them suggesting the chain must be impossibly weak.

But, says Facciola, "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.

The bicycle is built solely of wood and glue--all the way down to the drive chain . . . that works!"I was mostly concerned that the wooden chain would break. I researched the strength of different types of wood and built jigs to test the stresses that each of the chain's components would undergo during use. First, I used my weight (150 lbs) to see if the wood could endure this amount of force. Then, my father would stand on the jig. I calculated that my dad's weight would be twice the force each chain component would need to withstand. I made the specs high to ensure the chain and sprockets would work even if the wood had imperfections. During testing, I made adjustments to the chain's components, and once I had it figured out, I realized that completing the project was within my grasp."

Facciola says he spent almost 40% of all the time he invested in the project on the chain alone. Drilling the spacers took the better part of a day. "It didn't help that I made a small miscalculation and drilled nearly 1.5 times as many pieces as I needed!"

And then there's that great free-wheeling system Facciola created so he wouldn't have to pedal even while rolling downhill. (Of course, when you're riding a bike like Facciola's that has no brakes, it might be nice to have a direct-drive system when rolling downhill!)

Still, I am impressed that he not only thought of the mechanism, but was able to fashion it out of wood.

"I was unsure how many fingers . . . it should have and how strong they should be."

After Facciola put the contraption together, he found it was much too difficult to turn, so "I weakened each piece using [a] Dremel® [rotary tool], sanding off a thin layer of wood from each finger. Even after doing this, the system was still too difficult to turn, so I cut every second finger down.

"Afterwards, it turned smoothly, just as I wanted it to."

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