There is an interesting online article, from February 6, 2011, What's Stronger Than Steel? Spider Silk By CBSNews, that you may wish to visit. In the article, "(CBS) Contributor David Pogue of The New York Times launches a special four-part series on PBS' "Nova" this Wednesday night called "Making Stuff." And as we see in this sample from David's first episode, some of that stuff is VERY STRONG STUFF...."
Mr Pogue tells of visiting an aircraft carrier, the USS John C Stennis, and learning that, "Steel. Steel. Steel. Steel. Steel. The entire ship is made of steel!"
Mr Pogue goes on:
Of all the steel on an aircraft carrier, the steel the pilots probably care most about is the "arresting cable." When the plane comes in at nearly full power, the tail hook (with luck) will catch onto one of those cables and bring the plane to a quick but gradual stop.
A weakened cable could be fatal. So the Navy takes no chances: After every 120 landings, it throws away that expensive cable.
I thought, surely modern science can offer a material that's stronger than the steel in those cables - like, maybe, Kevlar, the stuff in bullet-proof vests.
Kevlar is not metal. It's flexible and it's stronger than steel, according to Tucker Norton, a ballistics expert at duPont. He demonstrated Kevlar's strength with the DuPont Bullet Shooter 3000. "Today we're gonna use this .44 Magnum bullet here against Kevlar XP, we'll see who wins," he said.
The Kevlar did not stop the bullet. "Well, not the first layer," said Norton. "But what's important is all the layers." Indeed, the bullet was still within the vest.
It turns out that Kevlar® could be used to make the aircraft arresting cable (arresting cables are also, by the way, used at the departure end of land-based military runways); but, it is too expensive!
If you did not already know it, the article goes on to say that spider silk is five times as strong as steel (for the same cross-section, of course!) So…why not replace steel cables with spider silk cables? (Don'tcha know there’s a problem?!)
There is no easy/inexpensive way of mass producing spider silk cabling – or even of producing it in small batches. As the article, with text bolded (by me) for emphasis, says:
"It's sort of the holy grail in terms of fabric, in terms of the richness and the softness," said Nicholas Godley, who should know. He spent four years in Madagascar making a stunning, one-of-a-kind,11-foot cloth out of spider silk.
It is, he says, the largest sample of spider silk in the world. "And it took 1,063,000 spiders to make." And his "team" [the spiders - CC] did it by hand - harnessed on their back, with their abdomens that protrude.
It takes 96 strands to make one thin thread - and a lot of threads to make even a tiny sample.
The CBS article then goes on to talk about genetic engineering in research to (hopefully) provide spider silk more efficiently – using goats, for heaven’s sake! (Do go read the whole article if the genetic engineering interests you.)
More on Nicholas Godley’s work
From the same Ecouterre website that had the Photo of the vest, and an article about it, referenced in the previous posting, comes another article, Art Historian Creates World’s Largest Shawl Made From Golden Spider Silk by Jasmin Malik Chua, 09/29/09. The latter article includes two photographs of the shawl, including the one, below.
Photo by New York Times/Redux/eyevine
In addition, the article includes a photo of the golden spiders that spun the silk, below.
Photo by Simon Peers and Nicholas Godley
If you care to know more about the spider handlers and the processing of the fibers in the shawl, Wired Science has a great article with the details.
You are now privy to more than I ever knew about spider silk...except...as most of you probably recall, spider web strands were (may still be, for all I know) used as the reticles in optics.
From Elements: Environmental Health Intelligence comes the following short article.
Spiders
Spiders produce silk thread that is extremely light, fine — only 1/200th of a millimeter in diameter [33] – and has the tensile strength superior to that of high-grade steel [34]. Spider silk has played an important role in sighting instruments since the 17th century when Robert Hooke, a British natural philosopher invented the reticle or cross hairs (8F). Silks threads from cocoons spun during warm weather were used in the eye piece of instruments used for surveying, astronomy and then telescopic gun sights [35]. Threads were cut into strands and positioned into the characteristic cross shape before they were installed in the scopes. The reticle increased the accuracy of measurements. Hooke’s telescope, equipped with cross hairs, allowed him to detect the rotation of Jupiter and Mars as well as discover Jupiter’s Great Red Spot [36, 37].
The process of creating a reticle was quite delicate. Spider silk strands were first stretched over a notched ring to form a cross and then they were secured in place with gum, varnish or beeswax [38]. Once the silk was secured, the sight could be incorporated into the eye piece of the instrument.
Spiders’ contribution to occupational Health and Safety occurred mostly during WWII. The spider silk used for making cross hairs allowed soldiers to “estimate the range to objects of known size, the size of objects at known distances, and even roughly compensate for both bullet drop (cause by gravity), and wind drifts at known ranges with a reticle-equipped scope” [39, 9F] preventing unnecessary accidents and loss of life through improved accuracy.
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