Cyclists and recyclists out there take note: a clever chap has developed a fully functional bike built of cardboard and recycled car-tire rubber. It’s projected to cost just $10 to produce, weighs just 9 kgs and can carry a rider weighing 220 kg.
The inventor is a chap named Izhar Gafni; he was profiled recently in The Economist’s Technology Quarterly (December 2012);
The first bicycles were made of wood. Cycle manufacturers then switched to steel tubes. These days, for high-end bikes where weight is at a premium, they use aluminium alloys or even carbon fibre. But Izhar Gafni, an amateur cyclist who owns a number of such fancy bikes, wonders whether the original inventors had a point. He proposes to go back to using wood—or, rather, a derivative of wood, namely cardboard.
Mr Gafni, who is based in Ahituv, Israel, spent years trying to work out how to make a cardboard bicycle able to support the weight of a human being. The trick is twofold. First, he folds the cardboard—commercial-grade material, made from recycled paper—to increase its strength. (He worked out the exact pattern of folding for each of the machine’s components using the principles of origami.) Then, once it is folded, he treats the result with a proprietary resin that holds it in shape and stiffens it, before cutting it into the form of the component required. A second application of resin renders the component waterproof, and a lick of lacquer makes it look good. The result, Mr Gafni claims, is stronger than carbon fibre.
The bike’s frame, wheels, handlebars and saddle are all made of cardboard in this way, and then fitted together. The tyres—again harking back to the early days of cycling—are composed of solid rubber, which is recycled from old car tyres. That makes the ride a little harder than if the tyres were pneumatic, but means they cannot be punctured.
The chain, based on the timing belt of a car, is also made from car-tyre rubber. The pedals are plastic recycled from bottles and the brakes are recycled too, though Mr Gafni is not yet ready to disclose the details. The finished product weighs 9kg, a bit less than an ordinary bike, and can carry a rider weighing 220kg.
Mr Gafni’s target market is the poorer countries of the world. Because manufacturing the cardboard bike will, he reckons, cost $9-12 a unit, his design is far more affordable than a steel-framed bike. But people in rich countries may be interested too. In Tel Aviv, the commercial capital of Mr Gafni’s native land, 2,000 stolen bikes were recently put on display by police, for their owners to claim. If bicycles cost less than the locks that chained them to lampposts, thieves might not think it worthwhile to steal them.
In a recent interview with the AP’s Ori Lewis, Gafni said:
“I was always fascinated by applying unconventional technologies to materials and I did this on several occasions. But this was the culmination of a few things that came together. I worked for four years to cancel out the corrugated cardboard’s weak structural points,” Gafni said.
“Making a cardboard box is easy and it can be very strong and durable, but to make a bicycle was extremely difficult and I had to find the right way to fold the cardboard in several different directions. It took a year and a half, with lots of testing and failure until I got it right,” he said.
Izhar Gafni, 50, is an expert in designing automated mass-production lines. He is an amateur cycling enthusiast who for years toyed with an idea of making a bicycle from cardboard.
Cardboard, made of wood pulp, was invented in the 19th century as sturdy packaging for carrying other more valuable objects, it has rarely been considered as raw material for things usually made of much stronger materials, such as metal.
Once the shape has been formed and cut, the cardboard is treated with a secret concoction made of organic materials to give it its waterproof and fireproof qualities. In the final stage, it is coated with lacquer paint for appearance.
In testing the durability of the treated cardboard, Gafni said he immersed a cross-section in a water tank for several months and it retained all its hardened characteristics.
The bicycles are not only very cheap to make, they are very light and do not need to be adjusted or repaired, the solid tires that are made of reconstituted rubber from old car tires will never get a puncture. “These bikes need no maintenance and no adjustment, a car timing belt is used instead of a chain, and the tires do not need inflating and can last for 10 years.”
The urban bicycle, similar to London’s “Boris bikes” and others worldwide, will have a mounting for a personal electric motor. Commuters would buy one and use it for their journey and then take it home or to work where it could be recharged.
He said that as bicycles would be so cheap, it hardly mattered how long they lasted. “So you buy one, use it for a year and then you can buy another one, and if it breaks, you can take it back to the factory and recycle it.”