From: email@example.com (Ian Okey)
Subject: Re: what is 100R mean in a schematics?
Date: 24 Dec 2002 01:06:35 -0800
References: <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org> <3E07C2CF.email@example.com>
NNTP-Posting-Date: 24 Dec 2002 09:06:35 GMT
Rick Merrill wrote in message news:<3E07C2CF.firstname.lastname@example.org>...
> William Meyer wrote:
> > Lewin A.R.W. Edwards wrote:
> >>I read a diatribe pro-avoirdupois, slamming metric measurements, in
> >>one of the EE journals just last month.. I think it was EDN? It's in
> >>the trash now, I'm not hunting. I can't understand the attitude. Of
> >>course, this gentleman probably expects to go to the supermarket and
> >>buy a few drachms of allspice, a gross-nip of milk, a 1/8th-rood roll
> >>of cling film, etc.
> > By now, I suspect most Americans are reasonably at ease with metric measures, where they find them.
> Ah ha! I have a horror story: I'm working on this co-linear robotic arm for
> machine tools and they tell me it's a 5 pitch screw and the original code
> (that didn't work) had "linear_pitch=5" so I let it be. But the system was
> never accurate over large distances. finally I measured diameters,
> counted gear teeth and then put
> a vernier caliper to the lead screw: it had a pitch of 5.0746 (my measure)
> per inch! It turns out to be a metric screw with a pitch of "5" , 5 mm
> per thread that is! So linear_pitch = 5.08 and now i'm right on the mark!
> There seems to be little incentive to make a wholesale conversion of systems.
> > One thing that galls me is the increasing appearance of mechanical products that contain threaded fasters of both Imperial and metric forms. I suspect that the metric fasteners have been used as an alternative to American fine pitch. It just makes it a PITA, having two sets of wrenches in play on a single product.
A couple of years ago a friend was out shopping, in the UK, with his
wife. They were in one of those department stores with the snooty,
blue-rinse sales assistants. She selected some dress fabric and asked
the husband to get 5 yards of the material. (They were of the imperial
The husband took the roll to the counter and asked for the 5 yards as
"Sir, we sell fabric by the metre, not the yard", came the haughty
"OK", he replied, "Can I have 5 metres, please."
The assistant proceeded to measure out the fabric.
"By the way", he continued, "Can you tell me how wide the material
"Certainly Sir", she replied, "ONE YARD."