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Top Gadget of 2006 — The HurriQuake Nail
eldavojohn writes "Popular Science is naming its Best of What's New of 2006 and the one at the top doesn't have much to do with circuitry or computers. Instead, it's a nail. Not your average nail though, the HurriQuake nail [flash] spent six years in development." From the article: "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 issue is not that the structures can't handle the winds. It is that the construction codes are not being followed by the builders. Construction is so poor because of cost-cutting by contractors and/or unskilled labor and cutting corners. This was true with Andrew (Miami) and continues to be true. If contractors built to the code and inspectors held them to it, alot of the damage seen would not occur. I have a house that was only 5 miles from the eye of Hurricane Charlie (140+ mph winds) and suffered minimal damage (a few pieces of soffet blown off, no shingles or other damage). But ... we watched the contractors and ensured that they did everything by the book. Neighbors saw their (oftern much more expensive) homes literally blown to the ground. Older structures (60's/70's) also saw little damage.
... just make sure the builders build to the code. Adding a better nail won't cure sloppy cost-cutting construction.
So
Normal screws the size of nails tend to fail in shear at much lower stress. This is not bullshit.
Larger screws made out of stronger alloys don't, but are typically too big to usefully stick a 2x4 to another 2x4, or hold a sheet of plywood into a 2x4 with typical installation accuracy. And require a pre-drilled hole, which at least doubles the time to install. These screws are not useful for typical building construction tasks. Cracking the wood all to hell installing oversize nails or screws incorrectly is far from the best solution.
Wood is a hard material to join really well. You can do all sorts of half-ass methods and get two pieces of wood to stick together adequately, but doing a really good job is a lot harder. Because it's got grain and fiber, you need a lot of bearing surface to avoid the connector pulling out. Screws do great at that, but have less shear resistance, and lower cost screws are too brittle and crack right off in shear (and sometimes in tension). Nails are great at shear and are made out of alloys that rarely crack, but can pull right out. Boat nails, ring nails, other stuff is out there, but this seems to be a pretty big advance in balancing the shear and tension capabilities, ease of installation, etc.
For absolute optimal strength, pre-drilled carefully sized screws work pretty well. This nail should be about as strong, but about 10% the effort to install, and probably a tenth the cost for the fastener.
There was a time that it was safe to assume that people at least had built a treehouse or some such and had a clue about basic woodworking techniques. Apparently that time is now past.