The variation in the threads of the dowel screws of spectacle frames.
British Standards specify a very small number of screw sizes as being acceptable for use in spectacle frames. We have measured the screw sizes of 50 frames, selected at random from the stock of Glasgow Caledonian University Clinic and have shown that very few of the screws used conform to these standards.
Davidson
M P
MP
Department of Vision Sciences, Glasgow Caledonian University, UK.
Mitchell
J W
JW
Walsh
G
G
D004867:Equipment Design; D005139:Eyeglasses / Q000592:standards*; D012016:Reference Values; D006113:United Kingdom