22-06-2022, 08:11 PM
(This post was last modified: 23-06-2022, 07:23 AM by Colin Wilks.)
Hi Henry
On my 1934 car the spanner for this nut is 5/8" BSW so suggests a Whitform thread, although the dimensions you give are a spit off M20 x 1.25mm. None of which is likely to help you at all I'm afraid, although Tracy Tools have some esoteric sizes in their taps listings. There seem to be a number of Admiralty threads on Austins, which are all bastard sizes. They are a hangover from Austin's wartime contracts. A mate with a lathe and some 28mm hex bar is probably what you need if noone has a nut they'll sell you.
On my 1934 car the spanner for this nut is 5/8" BSW so suggests a Whitform thread, although the dimensions you give are a spit off M20 x 1.25mm. None of which is likely to help you at all I'm afraid, although Tracy Tools have some esoteric sizes in their taps listings. There seem to be a number of Admiralty threads on Austins, which are all bastard sizes. They are a hangover from Austin's wartime contracts. A mate with a lathe and some 28mm hex bar is probably what you need if noone has a nut they'll sell you.