What is earliest use of Phillips-Head Screws in SS/Jaguar?


(Roger McWilliams) #1

Hi foliks, what are the earliest uses of Phillips-head screws in the Jaguar lineage? These heads provided much quicker centering for screw attachment than standard slot screws. They became practical as machining capabilities improved in the 1920s but I think were not widely adopted in European arena until after 1945.

The Mark V has at least 3 Phillips-head screws as original. They are on the electric motor casing (attached to the wiper transmission case) of the Lucas windshield wiper assembly. Date on one in my garage is March 1950.

What is the earliest factory use of Phillips-head screws on the cars to your knowledge?


(Rob Reilly) #2

I can confirm the use on Lucas wiper motors, as I have five Phillips cross heads on the one on my Mark V dated 1-50, which has been in my hands since 1969 and I believe to be original to the car.
I find none at all on my 1938 SS.

When I worked for a furniture factory we used them because assembly time with power tools was so much faster than with other type heads.


(Foggyoo) #3

Are you sure you dont mean posi-drives?


(Rob Reilly) #4

Nope, Phillips, patented in 1936 US#2,046,837 by Henry Phillips of the Phillips Screw Co. (although actually invented by John Thompson and sold to Phillips).



Posidrive was patented in 1962 by GKN.