Edwin Pawlowski wrote:

| There are absolutely no valid reasons NOT to use metric. There are
| plenty of people afraid of change. Use it steady for a few days
| and you'll wonder why we did not change decades ago. We use it for
| our money, we use it for some beverages.

I'd like to agree, but can't. I came up with a gizmo (photos at link
below) that allows ShopBot users to zero all three axes to a jig or
workpiece in less than a minute and a bunch of guys wanted 'em for
their shops. The first customer was in Sweden so I figured it'd be
cool to go metric...

Ok - I needed aluminum bar stock at _least_ 3/8" thick (1/2" would be
better) and went to the catalog. No metric stock available - so
ordered 1/2" x 6" x 72". Shrug.

Now I needed smaller stock thicker than 1/16" and wider than 1/2".
Back to the catalog for 1/8" x 3/4" x 72". Shrug again. Told myself it
wasn't a big deal, that no one would care what the actual measurements
of these parts was, so system wasn't important.

Then I needed button head cap screws to attach the thin pieces to the
edges of the thick one. Hmm - M5 x .8 x 12 (3mm key) are $14.27/C and
#10-32 x 1/2 (1/8 key) are $7.76/C. At this point my enthusiasm for
metric was beginning to fade a bit.

So I flipped to Allen wrenches. 3 mm hex keys were listed at $11.95/C
and 1/8" hex keys were listed at $5.85/C. (I wrote 'em down)

On to spiral-flute bottoming taps - a #10-32 was listed at $8.20 and
an M5 x .8 was $13.45 - I only needed two (I've learned never to order
just one of a given tap size because that's /inviting/ Murphy to the
party.)

I already have a set of fractional, numbered, and letter size drills
(#10-32 needs a #21 drill for the tapped hole and a #9 for clearance
hole) from Harbor Fright. I turned to look up the price on a but for
an M5 tapped hole and realized that my handy char didn't provide any
info as to what size bit I needed for /any/ metric tapped hole.

Added up the costs I /did/ know at that point, shrugged a last time,
and picked up the phone to order everything in inches.

Would you have done differently?

(The software that goes with the gizmo has been written to
automatically set itself up wo work in either inches or mm at
runtime - I figured that I owed my metric friend at least that much
consideration.)

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/SuperZero.html