Screw making in 18th century

[Welling]

Does any one know how screws were made in the 18th century before the advent of machines. My great great grandfather was a screw maker in Burton on Trent in the late 1700's

[HowardKennitby]

This gives some indication and some names for further research

http://www.whitworths...rg/history.php?page=2

[Ankou]

see here

http://www.boltscience.com/pages/screw2.htm