It’s not a reply to any specific person in this conversation. It is just conversation to myself.

Metric system is absolutely scalable. Just use millimeters in machinery and small projects. When you work with bigger object - use meters. Length of cruise ship is 528 meters nobody will say 528.000 millimeters (it’s still right). When you measure furniture you go with centimeters 88cm by 120cm or 0,88 m by 1,2 m (Cheap IKEA?

Hmm. 35 mm European hinges? 32 mm European shelf spacing? Cross dowel with M5 bolts? Slides. Who cares about this foreign crap!) Use kilometers for distance. When you work with semiconductors or smaller object use micrometers or nanometers. Simple. The same units, different order.
1km=1000m=100.000cm=1.000.000mm. Simple again. Can you recall how many yards, feet and inches in one mile? Why my odometer shows 0.4 miles? But my in law said make a left turn in 800 feet. Are we there yet?!
where is anybody?!
I need directions!
I’ll buy GPS.
Soon.
Immediately after New Year.
2012
or 2020.
Whatever.
Do I want to call her to clarify directions?
Not really.
I’ll make my math. ;D
When you work with stock its marked 1x3, but… it’s really 3/4x2.5. And what about 1x10? Is it 3/4x9.5? Nope, it’s ¾ x 9.1/ 4. Oops again! It’s a little bigger than ¾, so adjust your dado or make 2 passes with your ¾ router bit. I bought a plywood in Home Depot, guess what? It’s undersized! Hurray! I don’t need ¾ bits anymore; I’ll use ½ instead.
In two passes.

Metric system is a really system. (Just like our adorable Festool

) 1 liter is 1kg of fresh water. Sorry, what is one liter again? It’s a cube 10cm x10cm x 10cm. How many oz in one lb? And what about liquid oz in gallon? What is one ton? It’s exactly 1000kg. No more, no less. How many lbs in 1 ton? Let me think… 2202.64 lbs! Sounds much better then just one tiny ton. One milliliter? It’s precisely equal 1cc. You don’t buy pharmacy by lb or oz – only by milligrams.
Try to mark 7 equal spaces on 10 feet board? It’s hard to do. You have to deal with fractions. I’m not so well in math, but it keeps my brain busy. Now try to do the same in metric. It’s much more simpler! What about drill bits? Which one is bigger 13/16 or 15/32? Now compare to 5,5 mm and 6,0 mm.
25,41 mm sounds funny! 1mm is 1/25th of inch.1/10th is 1/250th of inch, 1/100 is 1/2500th of inch. Yes!!! We can provide space rocket technology precision on bare wood! Now I have to keep my cabinet in special camera with constant temperature and humidity. Can you notice difference between 25mm an 25,4 mm? Really?
How many SAE bolts and nuts are in “American” car? Not so much, most of them are assembled in Canada or Mexico. “European” or “Japanese” cars – have none, but they were assembled on US soil. Its' metric again. I have to keep two sets of wrenches and heads just for this purpose. It’s really convenient, trust me. Two nice boxe$ of really nice chrome-vanadium big boys’ toy$ in two drawer$.
Try to explain to European what is 5/16” bolt. OK? Why its better then M8? OK, Can you use it outside US? Yes, but only in our equipment. Fine! It was simple questionnaire. Now try to explain what is 1x12x8 piece of lumber. Do you succeed? Yes! Now question: why it is not the same as 4 boards 1x3x8? Because, because it’s a tradition… And I missed something: 1”x3”x8’ Inches, feet. Now calculate one board 300mm x 18 mm x 2500 mm or 4 boards 75mm x 18 mm x 2500 mm boards. (75mm approx. equal 3”) Is it still really hard work with decimal numbers? What? REAL woodworkers don’t buy milled wood? Sure.
How many people live in US? More than 300 millions! And we are using wonderful Imperial system for some applications! How many people live outside US? Just a little bit less than 6 billions, and they are using useless and inconvenient metric system.
PLease don’t ask why 12PM goes before 1PM, I don’t know.

Yes, it’s hard to accept metric system, but it’s matter of time when we’ll use it. :-\
Good luck everybody!