Metric Grief

By Bobby Neal Winters

If you talk to men of a certain age, you will run into a lot of strong opinions concerning the metric system.  To keep you from dying from suspense let me tell you now: They don’t like it.

Words get used. Certain words that at my house we call “magic words.”  They may be called that because they make women and children disappear.

For my part, I’ve tried to retain a neutral stance.  This is because I’ve taken quite a few science classes in my time and the metric system is there.  The metric system was designed by scientists for scientists.  The basic unit for length was originally defined in terms of the distance from the North Pole to the equator. (I guess they were thinking about Santa Claus taking a tropical vacation.) 

With scientific precision, they didn’t define units for weight. Instead they defined measures of mass, which is related to weight but does not depend on the strength of the gravitational field.

And everything is based on 10 to make the mathematical calculations easier. Everybody wants to make math easier, right?

These are all good things.

For years I’ve listened. For years I’ve wondered why all the emotion.  

One reason is that people just don’t like change.  And I agree here: Change is Bad.

There is another reason to intensify the first: The change has been slow.  There is wisdom that goes all the way back to Machiavelli at least.  He said that if you are doing something that the people like, do it slowly, but if they don’t like it do it fast.  Kind of like when Michael Corleone took care of family business. I’ve heard mom’s put it this way: You’ve got to pull off the band-aid.

But we’ve done the change-over slowly, and now we have two competing systems at work in the workshop: Metric and American. (And I use American instead of Imperial because while they are similar, they are different.)  When I go to deal with a nut, if it is metric, I will only have my American tool, and if it is American, I will only have my metric tool.  (And don’t tell me to have both open, because they are like USB plugs. Even if you are right the first time, you are wrong.)

This part of it causes the most noticeable grief.  It is what evokes the most magic words.

There is another, deeper problem that we slipped right past. It is taken as a given that basing everything on 10 makes the math easier.  While it does for scientists and engineers, it does not in the woodshop.

Here I will use my standing as a mathematician cum woodworker to state that base 10 is not the best number system to use in woodworking.  To begin with, we only use 10 as a base anyway because we have 10 fingers.  It’s only divisible by 2 and 5.  This means we can tell if a number in base 10 is divisible by 2 or 5 by just looking at the ones digit. By way of contrast, 12 is divisible by 2, 3, 4, and 6, which would make that task twice as easy.  

Not that I am advocating for change.  Change is bad.  Just think about the magic words that would be used during that changeover.  No, we will stick to base 10 in writing our numbers.

However, in woodworking, we often take half of something or a third of something.  This makes using a foot-ruler handy because you can take a half or a third of a foot quite easily.  More importantly, while metric rulers are calibrated in tenths, American rulers are calibrated in halves, quarters, eighths, and sixteens.  

There is nothing about the inch that demands that rulers be calibrated this way, but it’s the way it's done.  It’s the way we think about it.

One could take a metric ruler and mark it in centimeters, half-centimeters, quarter centimeters, and so forth.  (And we do mark five millimeters which is half a centimeter, but that is as fine as is gone in that direction.)  That isn’t done because the point of the metric system is to be in tens.

There is not as much metric grief in the woodshop as, say, the auto shop, because after a certain point measuring isn’t done with rulers. Instead of relying on rulers and numbers, we transfer measurements directly.

Eventually, all this will be behind us. After many magic words are uttered, metric will win.  This is inevitable.  But until then we will proceed and inch, a half-inch, or maybe even a sixteenth of an inch at a time.

Bobby Winters, a native of Harden City, Oklahoma, blogs at redneckmath.blogspot.com and okieinexile.blogspot.com. He invites you to “like” the National Association of Lawn Mowers on Facebook. Search for him by name on YouTube.