Saturday, September 17, 2005

Forbes.com - Magazine Article: "he need for a screw with threads shaped to mate with the substance it is penetrating has always been out there. But the screw is so simple and cheap--most cost less than a penny apiece to make--that it has been easier to design around its deficiencies than to come up with a better model. But LeVey, 40, says he was 'too dumb'to listen to naysayers; with his name on 19 patents and with 18 more pending, he thought it was silly to keep working around the problem when he could try making a better screw.

LeVey's first target was the concrete screw. He bought a chisel at Home Depot and studied the business end of it. If only he could wrap teensy chisel tips into the threads of a screw, it could chip its way into a tight seat instead of compressing and cracking the concrete. He traveled to ITW factories around the country, asking the wizened experts how it could be done. 'I got laughed out the door,' LeVey says.

Screws are made, oddly enough, by squeezing metal rather than cutting it. A steel or alloy blank, a cylinder with no threads, is rolled between two heavy dies that are grooved with diagonal lines. The blank is put under so much pressure that metal is squished into the diagonal grooves, forming a threaded spiral. Manipulating the shape of the threads using this method, called thread-rolling, was thought to be impossible because it would be too hard to control the structure of the screw if metal oozed into odd shapes."

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