I keep cutting things short!!

[DeformedTree]

I hear what you say about "cm" and I can even see the "problem" you're addressing - but to be honest, for native metric users, it simply isn't one. It is done/used every day like that. And the process of simply changing the decimal dot feels/is natural.

Everything above 1m would mean a 4 figure number in mm. That's not really practical to work with (at those lengths), that's why cm are used. And it's the same vice versa: a 12 mm drill bit "makes more sense" than a 1.2 cm drill bit. It just "naturally grew/ evolved"

But I guess it all comes down to what you are truly used to. I bought myself a tape measure that has a metric and fractional scale, just to better understand FOG posts when fractional measurements are used, to get a "feel" for it, so to speak. And I'm sure, if I started to do projects with inches/fractional measurements, I'd make the same mistakes.

Kind regards,
Oliver

So while you aren't wrong if you grew up using cm and mm back and forth, as as been brought up in other threads, even in metric countries, usage of cm is limited.  From working with folks around the world, and some comments here, it's understood there is some heavy cm usage in northern parts of continental Europe  (parts of Germany, lands to the northwest), else where they aren't used, and those folks have the same issues and grew up metric.

I use metric in my professional carrier, we do it all in mm, there is no cm.  Going over 1m in mm is not a issue.  You would have to hit 10m before a discussion of this would even come up. Not many things get that big, and if you did, you would just use meters.  But calling out say 2125mm on a print is perfectly normal. It's also how drawing standards and dimensional control standards work.  If metric, you use mm, if inch, you use inches. I have worked with many people/companies from many European Countries, haven't seen a cm yet.

Around my house, when doing stuff in metric, i do it in mm, have done wall framing in it just fine.  Cutting a stud to 2286mm, not problem, no way in heck would I try doing 228.6cm  2286 is just so much easier to think than 228.6

The real core issue is simply why tape measures a generally in cm?  I've looked into ordering some from other countries just to get mm ones. It's not like you find inch tape measures that are in yards  (yes they do in fact exist in some niches),  sure it's a unit that exist, but outside of sports we don't use it.  Tapes marked out with cm,  is like finding tape measures in yards instead of feet/inch.

 

[Svar]

So while you aren't wrong if you grew up using cm and mm back and forth, as as been brought up in other threads, even in metric countries, usage of cm is limited.  From working with folks around the world, and some comments here, it's understood there is some heavy cm usage in northern parts of continental Europe  (parts of Germany, lands to the northwest), else where they aren't used, and those folks have the same issues and grew up metric.

Not quite, cm is used in everyday life everywhere. Nobody expresses things of human or furniture scale in mm. Look at IKEA labels, for example. To say someone is 1815 mm tall would be really strange. You'd say 181.5 cm. Strictly mm are more common in design or engineering. Once you go down in scale, sure, 18 mm ply, 40 mm board, 50 mm screw.
I've never met a person outside of US who had "issues" with cm and mm. I'm not being condescending, there is just no issue, the two are an order of magnitude apart. If a drawing calls for 70 cm wide table you wouldn't measure and cut it 70 mm (3") wide by accident, not even blindfolded.
Earlier people pointed out inconvenience of rulers in cm. This is how it's supposed to be. You wouldn't label an imperial tape in 1/32" where instead of 12" you'd read 384.

Tapes marked out with cm,  is like finding tape measures in yards instead of feet/inch.

Tapes marked out with cm is like tape measures in inches, which is how they usually are. People use cm in situations where you use inch in US. A chair is 18" tall, a chair is 45 cm tall. That's why most rules/tapes are in cm.

Also, I never cut thing short.

 

[ChuckM]

Snip.
To say someone is 1815 mm tall would be really strange. You'd say 181.5 cm.

My Canadian driver's licence (not license [tongue]) says I'm xxx cm in height & xx kg, not xxxxx, gm in weight. Even though we've gone metric as a country (km per hour, for example), we still buy lumber by board foot, and label sheet goods as 4 x 8, etc. The truth is, whether I use imperial or metric or a mix of the two, I need to be careful to avoid making mistakes. Patience and carefulness go hand in hand a long way in getting good outcomes in fine woodworking no matter what systems or tools you use.

 

[Frank-Jan]

My Canadian driver's licence (not license [tongue]) says I'm xxx cm in height & xx kg, not xxxxx, gm in weight. ...

Why would someone's weight be printed on a driver's licence? My weight is pretty variable, and my European/Belgian driver's licence doesn't have an experation date (current one is issued 2008 because I lost my wallet)
I just checked my canadian passport, my weight isn't mentioned in that.

 

[ChuckM]

Interesting question, and you can find all kinds of answers (guesses) on the web why people think weight is included on the licences. Not every province (or state in the US) adopts the same standard: Quebec or Ontario, for example, doesn't collect weight for its driver's licences. I know some (all?) provinces issue licences that can list your gender as "X".

 

[DeformedTree]

My Canadian driver's licence (not license [tongue]) says I'm xxx cm in height & xx kg, not xxxxx, gm in weight. ...

Why would someone's weight be printed on a driver's licence? My weight is pretty variable, and my European/Belgian driver's licence doesn't have an experation date (current one is issued 2008 because I lost my wallet)
I just checked my canadian passport, my weight isn't mentioned in that.

In the US, all licenses have persons weight, along with a bunch of other info to help match the license to the corpse.  Worse now is they have bar codes that businesses scan (some states are banning this practice, except for those it was intended for (smoke/booze sales, cops).  Yes, your weight changes, so does our hair.  What if you had a beard the day of the photo and the next week shaved it off, new glasses, got a perm, etc. 

 

[AlexThePalex]

even in metric countries, usage of cm is limited.  From working with folks around the world, and some comments here, it's understood there is some heavy cm usage in northern parts of continental Europe  (parts of Germany, lands to the northwest), else where they aren't used, and those folks have the same issues and grew up metric.

No. Simply not true.

For anything human-size, and the objects humans work with, cm is the preferred and most used unit because it relates most to our human size. People in all metric countries use the cm most of all and are very used to them.

I use metric in my professional carrier, we do it all in mm, there is no cm. 
.....
I have worked with many people/companies from many European Countries, haven't seen a cm yet.

In science and engineering the cm is banned. This is done to avoid confusion. In those fields, you often have to put in measures in computers and machines, on drawings and plans, and using the cm proved to cause too much mistakes with the comma. So they made it a standard to only use mm and m because they are a factor 1000 apart so mistakes are easy to spot.

Now don't tell us science knows better, that's completely irrelevant. Science knows what's best, in THEIR field.

But for normal days use, the human psyche relates best to numbers that are not too big, and are whole numbers, so no fractions or commas. If you pick up a pen and judge its size, you don't say it's 0,15 meters or 150 millimeters, you say it is 15 centimeters. Because we like 15 as a number best.

Cutting a stud to 2286mm, not problem, no way in heck would I try doing 228.6cm  2286 is just so much easier to think than 228.6

Dead wrong again. 228,6 is easiest to remember and comprehend. Looks like you're struggling with metric, don't blame the system because you are not used enough to it yet. In fact, with a number like that, you just know you're in the 2 meter range, and remember it like 28,6 and add the 200 automatically without thinking.

The real core issue is simply why tape measures a generally in cm?  I've looked into ordering some from other countries just to get mm ones. It's not like you find inch tape measures that are in yards  (yes they do in fact exist in some niches),  sure it's a unit that exist, but outside of sports we don't use it.  Tapes marked out with cm,  is like finding tape measures in yards instead of feet/inch.

Very odd comment. cm to inch factor = 2,54 and cm to yard factor = 91. Meter to yard factor = 0,91.

Looks like the cm is MUCH closer to the inch than to the yard. And the meter is closest to the yard.

So why would you compare a tape in cm to a tape in yards?

As I said above, all metric tapes are in cm because that size is understood best by the human mind. But yes, why would you, with your limited experience in metric believe those 7 billion people who grew up with it?

 

[six-point socket II]

So while you aren't wrong if you grew up using cm and mm back and forth, as as been brought up in other threads, even in metric countries, usage of cm is limited.  From working with folks around the world, and some comments here, it's understood there is some heavy cm usage in northern parts of continental Europe  (parts of Germany, lands to the northwest), else where they aren't used, and those folks have the same issues and grew up metric.

Not quite, cm is used in everyday life everywhere. Nobody expresses things of human or furniture scale in mm. Look at IKEA labels, for example. To say someone is 1815 mm tall would be really strange. You'd say 181.5 cm. Strictly mm are more common in design or engineering. Once you go down in scale, sure, 18 mm ply, 40 mm board, 50 mm screw.

(...)

Hi!

This is basically exactly what I tried to convey [member=68063]DeformedTree[/member] .

Yes, mm are used in (technical) drawings, for scientific purposes, (partly) in standardization and a whole lot of other things. Yes, mm is a scientific unit. People who work in the metal industry or with metal in general, tend to use mm over cm. But I honestly have no knowledge on how they communicate these numbers when speaking to each other, but sure, the drawing will be in mm.

But outside that world, "the spoken word" uses cm (or m).

So if I'm working with a neighbor on a shed, and we need to cut some battens. It goes like this:

How long does it need to be?

"One meter, eighty-six." or "One-hundred-eighty-six." or "One-eighty-six".

No one would say "One-thousand-eight-hundred-and-sixty". And none of the commonly used (measuring) tools would be able to display this.

If I ask for a drill bit, I ask for a "ten mm drill bit" or for a "eighty-six mm hole saw". If it's a long drill bit, it's a 400 mm drill bit, not a 40 cm drill bit.

I hope this simply adds to the understanding of how "we" naturally use these units. This is really how it's used everyday, hence it is not confusing for us. Just as natural, as the "fun fact" that (threaded) pipe diameters are still given in inch. It's a half-inch pipe, it's a 3/4" pipe ... .

Kind regards,
Oliver

 

[DeformedTree]

Cutting a stud to 2286mm, not problem, no way in heck would I try doing 228.6cm  2286 is just so much easier to think than 228.6

Dead wrong again. 228,6 is easiest to remember and comprehend. Looks like you're struggling with metric, don't blame the system because you are not used enough to it yet. In fact, with a number like that, you just know you're in the 2 meter range, and remember it like 28,6 and add the 200 automatically without thinking.

How is 228.6 easier to remember?  You just added floating point.  I'm not struggling with metric, nor not used to it.  If I'm going to go that route I would go 2.286 .

Humans want whole numbers, it's just easier.  The beauty of mm is you don't need to go the other side of the decimal much.  While I hate fractions and all their issues it's pretty easy to see why people used them verses decimal inches for so long before the computer age. 

We talk 2286 just fine.  Pretty sure when talking to folks from Europe the phone company doesn't translate their speech real time to make cm come out mm on our end.  Twenty-Two  Eighty-six  rolls off just fine verses  Two-Hundred Twenty-Eight Point-Six.

I sorta wonder if some of you guys say out numbers differently from us.

 

[AlexThePalex]

How is 228.6 easier to remember?  You just added floating point.

Because 228,6 is exactly what the tape says.

[attachimg=1]

I'm not struggling with metric, nor not used to it.  If I'm going to go that route I would go 2.286 .

Yes, you are. You show you constantly have to do conversions internally and decide what's best or not. If you were really used to metric, you would not think about it twice. Automatism.

I sorta wonder if some of you guys say out numbers differently from us.

We most certainly do, in fact, we speak an entirely different language.  Tweehonderdachtentwintig komma zes. [wink]

 

[Packard]

I avoid using a ruler whenever possible.  I directly transfer dimensions onto the lumber. 

For example, rather than measure the lengths of stock for face frame, I simply lay the stock over the box and mark the length on the stock. 

For the horizontal pieces I add two small pieces of the face frame to the piece being marked and come up with the correct size that way. 

I also use a story stick.  And sometimes I use a 4'  aluminum ruler and stair stops to mark the lengths.  It is not as direct but at least I don't have to read any numbers.

Stair stops (about $5.00 per pair):

 

[zapdafish]

lol,

I'm a story stick person but if the story stick is off, you are off everywhere.

Another step for me when prepping for cuts is I always put pencil lines where I am going to cut and label the sections between the pencil marks that correspond to some paper with all my measurements. Before the cut i do a quick re-measure to make sure it corresponds to the sheet. Then for each piece that has the same label, like L for table leg, I just lay the fresh cut piece over where I am about to cut and verify the marks. At least that way, the other 3 legs match the first leg if I happen to be off, lol

I think fastcap has a tape measure that takes pencil markings that might help with measuring mistakes. only problem for me is I misplace my tape measures all the time so I have a bunch of them scattered through out the shop and cant have a dedicated tape measure for something like that. even with 5 or so tape measures, there are times where I still cant find one.  [unsure]

 

[Julie]

Just another perspective from a novice woodworker with a machinist background...

I have a lot of trouble with centimeters. (I am trying to do all my woodworking in metric.)
As a machinist I work with inches and thousandths of an inch (milli-inches) such as 10.100 +-.005  and in metric I work with millimeters and decimals of the same. (I never use feet when machining. For long parts it is still just inches.)

In metric it is simple to go from millimeters to meters as it is just another decimal point.

So for example in woodworking, 640 is 640mm and 1250 is also 1250mm. 1.250 is in meters, which makes sense because you can't accurately cut wood to 1.25 millimeters.

I do have a question about fractions of a millimeter when woodworking.  How do you handle drawer slides that are 1/2" wide? The fraction in 25.4mm really bothers me.

 

[MikeGE]

I do have a question about fractions of a millimeter when woodworking.  How do you handle drawer slides that are 1/2" wide? The fraction in 25.4mm really bothers me.

I do all of my measurements in millimeters.  When it comes to drawer slides that specify 12.7mm, or something like this, I use 12 or 12.5mm.  There is enough lateral movement available in the slide rails to compensate for my laziness.