The Case for Metrics

[Jim McDonald]

Probably should have made this a blog entry, but figured it might get more discussion here.

Most American woodworkers are comfortable with the "English" system of measurements--inches and fractions--and all the math that goes along with it. I much prefer turning the fractions into decimals to do the math, but I am just as comfortable using the metric system and the easier math that base 10 affords.

During and after high school, I worked in newspapers where we mixed points (72 per inch) picas (6 per inch) and inches. Funny, we measured type vertically in points, width was picas and depth of pictures and pages was inches, so I got used to a variety of measuring systems. During high school in the 1970s, there was talk of the US converting to metrics and the howls for the public was deafening. Some road signs were listed dually in miles and kilometers, but it seems the only industry that TRULY adopted metrics was bottling. We seem comfortable with 750ml of liquor and 2 liters of soft drinks, but we can't seem to change length to groups of 10.

Later, I was a paramedic where everything was milliliters, milligrams or micrograms and had no problems moving the decimal places as needed to make the calculations.

Now that I am beginning to draw things I want to cut, I find myself leaning more and more on the "underside" of the ruler and using more and more metrics.

I don't try to convert one system to the other, I just know that if 8mm is not quite large enough, nine will do. In fractions, do I go to the 1/8th, 1/16, or 1/32 to make that increase and then, will I have to reduce the fraction to make it more readable? The millimeter jump is much more understandable and truly requires no factoring.

I can say that something is 37mm and you could convert that to 3.7 centimeters if you wanted, but you recognize that is 3 full and 7 smaller marks. If it's not quite right, go to 36 or 38mm. But if I were to give you 37/16ths of an inch as a measurement, you would be doing the math to figure it was 2 5/16ths inches. Now if this is not right, look at the math involved in making a one unit change.

Besides, a millimeter is just over 1/25th of an inch and who among us needs to go any tighter than that?

Just some ramblings from a Saturday morning before the coffee has fully kicked in.

[Sally]

What??? (smile)

[Lois from Mississauga]

Canada went metric in the late 70's. Kilometers replaced miles, Celsius replaced Fahrenheit, etc. Although I was just a little kid then, and we were taught metric in school, I still mix and match our measurements. I think it comes from the US being a close neighbor and its products still influencing us.

I use inches, pounds, cups and teaspoons (but will switch back and forth if one works better at the time). I avoid fractions at all costs and when needed, will switch to metric to avoid them. When getting to the large measurements, it all goes metric. Kilometers, liters, etc.

Temperature outside is always Celsius. But taking someone's temperature when they are sick is English - 102 sounds more concerning than 39), ...and for the oven - all recipes are in Fahrenheit. Then again, when looking at my weight, the smaller Kilogram number always looks better than the Pounds. (and I won't say how much either goes for right now).

I have often thought it interesting that we bounce from one to the other so randomly.

[Fran1942]

Metric is so much easier to work with. I agree. But as long as our lumber is sold in fractions. I will use that method.
Fran

[wood-n-things]

I wish we were in metrics. I remember the big push. Perhaps we could get some folks back to work putting up those dual signs again and converting to metric would add some new job I would thin.

[jim_mex]

Hi Jim -

I work around the world in factories associated with ceramic manufacturing ie tableware, sanitaryware and tiles. In all of these factories the units get mixed. We talk of 10 1/2" and 7" plates, 15, 20 and 33 mm tiles, toilets which have mm sizes yet couple to imperial plumbing fittings. plus we use machinery manufactured from all around the world with combinations of imperial and metric sized parts. My conclusion is that the attempt to change from imperial to metric will never succeed completely until industry makes a decision to go metric 100% and whilst there is still a massive call for spare parts in imperial sizes I can't see this happening. Personally I'm with you Jim, comfortable to use either system, although i will admit, metric makes calculations so much easier.

PS - my favourite here in Mexico is buying steel and lumber by imperial cross-section measurement and metric length . What a mess! LOL!

[Mick Walker]

Somewhere I read that 5/4 of all people have trouble with fractions.

[MikeyD]

As a machinest I convert everything to Thousands of an inch, even my wood working. I work in all the aformentioned except the typeset. I also have to deal with wire gage size of numbers and letters. Then there is the sheet metal gage sizes and the electrcal wire sizes. It can all get a bit confusing. As for me I will never change from the basic inch system because I would have to buy all new measuring equipment.

Mike

[Marsha]

I have adapted to both method of measurments, metric & imperial. I prefer to use metric whenever fractions become an issue, I've never been able to divide anything into thirds evenly. I never try to convert one to the other, if I need metric I use a metric ruler or tape measure. I know that 21 celcius is warm enough and 25 celcius is too hot for me, but I have no idea what that is in fahrenheit. I know I drive in the city at 60 kmh, and 100 kmh on the highway, because that's what it says on the speedometer and the signs on the side of the road, who cares what that is in mph, it's fast enough for me. When I buy sliced meat I buy by the slice, who cares what it weighs. When I bake I use imperial, cause it's there in the recipe book.
Nothing is black and white, I use what I need for the situation I'm in.
That's my 2¢ worth
Marsha

[saw dust]

Agree with most can use either but if I want something to be a tighter tollerance I opt to use metric measurements. saw dust