In article 20180418172431.4f76c30a@Mars,
Rob Morley wrote:
On Tue, 17 Apr 2018 11:58:09 +0100
Graeme wrote:

Well, yes, but measuring to a fraction of a mm with a steel rule
is not easy, particularly when the connection is buried under the
bonnet.

That's why you take the measurement with a small caliper, and transfer
it to a measuring scale or vernier caliper once you have it somewhere
more accessible. Calipers are cheap and very useful.

I'm sure 1/4 inch was the 'standard' automotive size back in
the day, and 6.3mm is close enough to 1/4 inch.

6.35mm is exactly a quarter inch, by definition - I expect they just
dropped the 0.05 for convenience rather than rounding it up. The
connectors are probably made something like 6.30mm male and 6.40mm
female for an easy fit (and they're probably not specified to 0.01mm
anyway).

Modern ones are perfectly compatible with the old 1/4" versions - same
across all the spade terminal range. Although some modern ones ain't as
well made as originals. Thinner brass.

--
*Why is the word abbreviation so long?

Dave Plowman London SW
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