Thanks for this John. This came from a US website. All the UK sites I have
checked for similar suppliers/items are virtually exclusively metric - only
very occasionally is an imperial dimension shown.
In looking at the US websites, there is quite a sprinkling of metric measures,
although sometimes it is obvious that the authors of the material shown do not
fully understand what they are writing about when using metric dimensions (e.g.
one site showed a bracket dimension of 120mm [sic] for one mechanism, and then
12CM [sic] for the identical item but including a clock face). Still, a very
positive sign that the US, even at the 'public' or consumer level, will show
metric measures where necessary.
John F-L
----- Original Message -----
From: John M. Steele
To: U.S. Metric Association
Sent: Friday, July 17, 2009 1:39 PM
Subject: [USMA:45411] Re: mix of measurements
My guess would be that the mounting hole sketch is direct from the
manufacturer, and needs to be somewhat exact. The other dimensions are all
clearance dimensions and can be rounded up to the next Imperial fraction with
no risk; those were probably measured or converted for the US (or UK?) market.
--- On Fri, 7/17/09, John Frewen-Lord <j...@frewston.plus.com> wrote:
From: John Frewen-Lord <j...@frewston.plus.com>
Subject: [USMA:45408] mix of measurements
To: "U.S. Metric Association" <usma@colostate.edu>
Date: Friday, July 17, 2009, 6:20 AM
Dear all:
I have been browsing the net looking for parts/mechanisms to restore
an antique clock I have. Many of the potential suppliers are in the US, and I
have found quite a mix of imperial and metric measures. Mostly imperial, but
metric here and there (likely when describing German or other non-US sourced
components).
The attached picture really intrigued me - don't know whether the
company on whose website it appears created it, or was supplied from elsewhere.
The font used for both the metric and imperial dimensions is the same, so
likely the same person added the mixed measurements.
Cheers
John F-L
