[Healeys] Threading

[Peter Svilans]

Dave:

Its an interesting story.  Morris, Wolseley and MG engines were all built at
the Morris Engines plant.  The French Hotchkiss company feared being overrun
by the advancing Germans in WW I, and moved their plant to Coventry in England
in 1915.  William Morris bought the plant in 1923.

Being a cheapskate, Morris decided to keep all the French tooling, and never
converted over to British Standard.  Car restorers have cursed "Morris' Mad
Metric" ever since.

But it doesn't end there.  Old French Metric is different than the modern ISO
Standard Metric form.  And as a concession to British motorists, Morris
decided to use Whitworth hex heads on his French Standard bolts so the
Whitworth tool kit wrenches could be used.  And it seems there were no
standards for this idea either, as an 8mm threaded bolt could have either a
3/16 W or a 1/4 W head, even on the same MG TC engine.

All in all, it would have been cheaper in the long run to switch over the
French tooling to British in the first place.

Britain first made plans to go Metric in 1965, and still hasn't committed to
it completely.

Best
Peter