instrument sizes

"Jim Carriere" wrote in message
...

Last random thought, I wonder what they do in parts of the world that have
left the dark ages and embraced metric

}:-)
that's the easy part:
-) if it's just a plain hole, find the proper length & diameter & fit
-) it it's threaded and needs to be,
run the next larger reamer (?) in metric, then proceed as above

for those unawa metric screws, bolts &C only have a diameter and a length
M4*40 means it is 40 mm long and will pass a 4mm hole,
now isn't that all there is to say?

Earlier, karel wrote:
...for those unawa metric screws, bolts &C only have a diameter and a length
M4*40 means it is 40 mm long and will pass a 4mm hole,
now isn't that all there is to say?

Um, no, not quite. Like inch-size fasteners, metric fasteners will
often have more than one thread pitch available. I know I've spent more
than a little time sorting M10 nuts into 1.25mm and 1.5mm thread
pitches.

"Bob Kuykendall" wrote in message
oups.com...
Earlier, karel wrote:
...for those unawa metric screws, bolts &C only have a diameter and a
length
M4*40 means it is 40 mm long and will pass a 4mm hole,
now isn't that all there is to say?

Um, no, not quite. Like inch-size fasteners, metric fasteners will
often have more than one thread pitch available. I know I've spent more
than a little time sorting M10 nuts into 1.25mm and 1.5mm thread
pitches.

Um, well, err, scratch...

In 30 years of shade-tree mechanics I never came across such a thing...
And I'm quite sure the thread pitch will be defined somewhere in DIN
for the various diameters
though I'd have to search for the reference text.

There's some creativity available across the pond!
Now to find some more useful application for it...
KA