[DrDavid]

Of course the conversions can get a little messy when going back and forth from certain listed figures.

For example, if a builder lists his/her standard nut width as 45mm (not at all unusual, by the way), this would convert in inches to something like 1 99/128. (And even that is not an exact conversion.)

So sometimes it's better in doing these conversions to forgo ultimate precision, and just settle for something in the nearest ballpark.

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