Spare wheel lid mounting screws

Spare wheel lid mounting screws NS 519/3D

The hinges (BD9374) are mounted to the spare wheel lid (BD9372  or BD11262) with (3 x 3=) 9 countersunk set screws and fit in “T” nuts (BD9909/1) placed in the plywood.

clip_image002 Hinges are fixed to these “T” nuts with ANF 3/16 thread

Official Jaguar code for the mounting screws is NS519/3D meaning ANF 3/16 x 3/8” CSK slotted set screw. However, since about 1950 the 3/16″ UNF thread doesn’t exist any longer. There are 3 possible alternatives:

  • The best equivalent is CSK Slotted No.10 x 32 threads per inch. Diameter for UNF 3/16″ is 0.1875″ and for No.10 is 0.190″. They are however interchangeable and have both the same 55° thread angle.
  • British Standard Fine (BSF) has a 3/16″ x 32 thread as well. Normally UNF and BSF have different “thread per inch” but in this case they are identical.
  • Also 2BA screws might fit if the thread hole is undamaged: it is about 0.1 mm smaller in diameter and (as the thread angle is only 47.5°) it will fit the UNF thread. The pitch is slightly longer (about 0.02 mm!) than the UNF version.


Diameter (inch)

Diameter (mm)

Pitch (TPI )

Pitch (mm)

ANF 3/16”





No 10





BSF 3/16”










Additional information on these thread types:
BSF has a Whitworth 55° thread angle, where as BA has a 47.5° thread angle. So these threads are not automatically interchangeable: in general a BA screw might fit a BSF thread hole if the diameter and TPI are close.

BA is taken from the 19th Century Swiss Thury thread. Its formulation was proposed by the British Association in 1884 and adopted in 1903. BA has in principle metric dimensions. No.0 BA is 6.0 mm diameter and subsequent numbers are in 0.9 progression. Multiply a BA diameter by 0.9 and you have the diameter of the next smaller size. BA screws are nowadays seldom seen and virtually exclusive to electrical fittings (e.g. Lucas) and instruments (e.g. Smiths).

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