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Old 22nd Jan 2015, 11:48 pm   #93
Phil G4SPZ
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Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
Posts: 4,735
Default Re: Technology related anachronisms on TV and in films etc.

I've no personal knowledge of this, but according to on-line sources, the earliest screw threads date from around 400BC (long before the first screw cutting lathe of 1770) and were used in presses, to generate sufficient pressure to extract oils and juices from olives, grapes etc. I may be wrong, but again, the maximum force that could be applied (by a right-handed operative) to the handle of a grape press would involve placing his or her right hand at the furthest end of the operating lever and pulling like mad. This action would require the screw to have a right-hand thread.

By all accounts, some early screw threads were indeed filed by hand!
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