November 28, 2006


Dr, Nail vs. the Monster (Tom Clynes, Popular Science)

In 1995 a Clemson University graduate student named Ed Sutt took off for a spur-of-the-moment trip to the Caribbean. But beaches and rum drinks weren’t on the agenda for this civil engineer. Hurricane Marilyn had just torn through St. Thomas, and Sutt was part of a team examining how and why 80 percent of the island’s homes and businesses had collapsed in the storm’s 95mph winds.

“The destruction was so complete in places that it was almost surreal,” Sutt recalls. “There were troops in the streets and military helicopters hovering overhead.” As Sutt moved through the wreckage of roofless and toppled-over houses, he was struck by the sense that much of the destruction could have been avoided. “In house after house,” he says, “I noticed that it wasn’t the wood that had failed—it was the nails that held the wood together.” [...]

During the HurriQuake nail’s six years of development, 14 major hurricanes and tropical storms destroyed hundreds of thousands of houses in the U.S. and inflicted an estimated $166 billion in damages. The U.S. hasn’t had a major earthquake since parts of the Los Angeles area were leveled in the Northridge quake of 1994, but around the world, thousands of people have lost homes and family members as wooden structures collapsed.

Although there are no precise statistics, Sutt’s research indicated that nail failure accounted for a substantial percentage of the destruction in these catastrophes. And when nails fail, it’s for one of three reasons. Either the nail rips its head through the sheathing, its shank pulls out of the frame, or its midsection snaps under the lateral loads that rock a house during high winds and earthquakes. Sutt’s job was to design a nail that resisted all three. “With the first prototypes,” Sutt says, “we proved that a bigger head has substantial advantages in terms of stopping the nail from pulling through the sheathing. But it couldn’t be too big, because it needed to fit into popular nail guns.”

As the Bostitch team tweaked the head-to-shank ratio, Sutt and metallurgist Tom Stall worked on optimizing high-carbon alloys, trying to find the highest-strength trade-off between stiffness and pliability—the key to preventing snapped nails. “Meanwhile,” Sutt says, “we were focusing on how to keep the nail from pulling out.” The team machined a series of barbed rings that extend up the nail’s shaft from its point, experimenting with the size and placement of the barbs. “You want the rings to have maximum holding power,” he says, “but if they go up too high, it creates a more brittle shank that shears more easily.”

The team tested hundreds of designs, looking for the best compromises. The late prototypes held fast, and Bostitch came out with a barbed nail with a larger head in 2005 called the Sheather Plus. But the solutions created problems of their own: As the barbs pierced the sheathing, they generated a hole that was slightly bigger than the shank, resulting in a loose, sloppy joint.

“We needed a way to lock the top of the shank into the sheathing,” says Sutt, who attacked the problem in a series of brainstorming sessions with his engineers. Their solution: a screw-shank, a slight twist at the top of the shaft that locks the nail in place. The combination of the screw-shank, barbed rings, fatter head, and high-strength alloy added up to an elegant solution to the failures that had plagued nails for more than two centuries. Sutt’s team had, in effect, reinvented the nail.

Tinkering matters. Thinking doesn't.

Posted by Orrin Judd at November 28, 2006 8:10 AM

Wrong. Technology:Science::Julia:Eric.

Posted by: Mike Beversluis at November 28, 2006 8:47 AM

The extra cost of the improved nails is $15 per house.

For $15, you hurricane-proof your house.

And they say engineering isn't cool.

Posted by: Mike Morley at November 28, 2006 9:45 AM

Or as they say at Toyota, "Ready, Fire, Aim".

Posted by: jeff at November 28, 2006 9:49 AM

For nails, yes. For lots of things like that, yes. For special relativity, general relativity, and orbital mechanics, no. Tinkering with that is fun (to be sure), but quite expensive.

Thinking also matters with respect to faith. Because what is nonsensical or evil is not worthy of our faith. Empiricism doesn't seem to work very well with faith and worship, now does it?

Posted by: jim hamlen at November 28, 2006 9:52 AM

faith precludes thought. it's nice that reason accords with faith, but unnecessary.

Posted by: oj at November 28, 2006 10:45 AM

> Tinkering matters. Thinking doesn't.

Wow. That's an amazingly concise self-validating statement. In fact, it's evidence of the highest order of thinking. Umm, but that makes it a self-refuting statement, which means it's nonsense, which means ..... AAAARRRRRGGGGGHHHH!

Posted by: Kirk Parker at November 28, 2006 12:45 PM

The point is not to think about it, just accept it.

Posted by: oj at November 28, 2006 12:51 PM

The point is not to think about it, just accept it

Or just lie back and think of England.

Posted by: Raoul Ortega at November 28, 2006 2:16 PM

For those interested in what the new nail looks like, click here. It amazed me that no one had thought of this before and that it was all done using private funds, without any government grants. The nails were designed to be used in existing nail guns. They double the wind resistance of buildings and increase earthquake resistance by ~50%.

Posted by: jd watson at November 28, 2006 2:44 PM

If faith precludes thought, then there is no way to judge (discern, differentiate, distinguish) anything. "Reason" alone is certainly a pit, but there has to be a reason for faith, otherwise we can all believe 6 impossible things before breakfast. And then turn around and believe 6 more at lunch. And so on. That is the road to the asylum. Of course, reason leads to the gas chamber.

Faith is difficult. Humility is difficult. Silence is difficult. Don't make the error of presenting faith as an 'easy' option, without any demands all its own.

Posted by: jim hamlen at November 28, 2006 3:57 PM

No there doesn't. If there's a reason for it then it isn't faith. Indeed, it's not reasonable to believe in the self, nevermind God. It's just a matter of faith. That's the Anglospheric insight that helped us avoid the wreckage of the Enlightenment.

Posted by: oj at November 28, 2006 4:53 PM

If by faith you mean something like Dr. Johnson's response to Bishop Berkeley's thought on empiricism and perception (kicking a stone, he said, "I refute it thus!"), then that is OK.

After all, a kick is sort like tinkering, no?

Posted by: jim hamlen at November 28, 2006 11:49 PM