willey@arrakis.nevada.edu (James P. Willey) (11/08/89)
From: James P. Willey <willey@arrakis.nevada.edu>
I was watching Newton's Apple on the local PBS station and they
mentioned something interesting. They claimed that the military uses
spider silk, especially from black widows, to make crosshairs. What
weapons use spider silk and why do they use it?
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James P. Willey willey@arrakis.NEVADA.EDU
Disclaimer: I'm unemployed, so my employer IS responsible for my opinions.
I wish someone would call time out,
They're welcome to disarm me,
We are the very model of
A modern techno-army.
(Robotech)woody@eos.arc.nasa.gov (Wayne Wood) (11/14/89)
From: eos!woody@eos.arc.nasa.gov (Wayne Wood) In article <11224@cbnews.ATT.COM> willey@arrakis.nevada.edu (James P. Willey) writes: > >From: James P. Willey <willey@arrakis.nevada.edu> > [query about spider silk deleted] at one time the reticles in binoculars and sniper scopes were made from silk... i don't know if it was spider silk... and i surely don't know if it was sepcifically black widow silk. it would appear that it is possible... i believe spiders spin a finer thread than silk worms thus providing a finer reticle. i also believe the reticles in spotting scopes for the 106 RR may have been silk... i didn't get to look through them too many times. the marine corps was using redfield and unertl [inertl? sp?] scopes on their sniper rifles when i left... you can check with either of those companies to see what they use. the redfield was 3x to 9x variable and similar to the "WIDEFIELD" [tm] scopes. the unertl's were 10x fixed. FREE EASTERN EUROPE! TEAR DOWN THE WALL! /*** woody **************************************************************** *** ...tear down the wall! *** *** -- Roger Waters, Pink Floyd *** ****** woody@eos.arc.nasa.gov *** my opinions, like my mind, are my own ******/
mmm@apple.com (11/18/89)
From: portal!cup.portal.com!mmm@apple.com I also have heard that black widow spider silk is commonly used for rifle scope crosshairs. I once knew a person working on an invention for a new type of scope, and he told me that a cross hair is made by picking up a spider, touching the tip of its abdomen to the rim which supports the crosshairs, stretching it over to the opposite side and touching the rim over there, then repeating the process for the other crosshair. Spider silk is both strong and thin. It also comes in its own applicator. I don't know what specific feature of black widows makes them desirable for the job; maybe its time to cross-post to sci.bio.
daveme%tekirl.labs.tek.com@RELAY.CS.NET (Dave Mead) (11/21/89)
From: Dave Mead <daveme%tekirl.labs.tek.com@RELAY.CS.NET> Cross-hairs in many early rifle scopes were made of Black Widow silk because of its high strength and fine diameter. Dot reticule scopes suspended a laquer drop on the nearly invisible strands. Later optical designs went to etched glass or other materials for cross-hairs. I am sure Kevlar strands now surpass spider silk for tensile strength, but before that they were the strongest fiber of that size. I doubt they are still used and Newton's Apple was citing dated material. Dave Mead Tektronix Labs