Slashdot recently posted a link to this fascinating (in a geeky sort of way) rundown of the Imperial (Metric) system and how it relates to paper sizing. Some of what followed in the discussion thread I knew, some I didn’t, but it was one of the more interesting threads I’ve read on /. in a while.
Having worked in the quick-print industry for something over a decade now, while I don’t normally deal with metric paper sizes, I’ve gotten very used to thinking in metric when setting jobs up. This is simply because the machines I was working with for quite a few years — the Xerox Docutech family — could be set to work in either inches or millimeters. No matter which base measurement you chose, though, you could then nudge an image by a tenth of your base measurement. Obviously, you had much finer control when attempting to align items if you could nudge by a tenth of a millimeter rather than a tenth of an inch, so setting the machines to millimeters became fairly standard practice for me.
Still, it’s obvious when doing this that the two systems don’t really work together very well. US Letter size paper is commonly noted as 216mm by 279mm, and US Ledger (11″x17″) is 279mm by 432mm, however, each of these are actually approximations, and off by a few tenths of a millimeter on each side. Still, kludgy or not, the benefits gained through the finer control was worth it.
After reading through the discussion, though, I really wish the US would finally switch over to metric.
Things I knew:
From the original post:
For those who enjoy a bit of math, did you know that in the Metric paper system, the height-to-width ratio of all pages is the square root of 2? This means that you can place two sheets of A4 side-by-side and they will equal an A3 sheet exactly, and two sheets of A3 will equal an A2.
On trying to enlarge or reduce between paper sizes (which never works well with US paper sizes), from SSpade:
11×17 is not the same shape as 8 1/2×11.
That’s the real beauty of A4/A3 etc. All the sizes in a given series (A00, A0, A1, A2, A3, A4, A5… or B1, B2, B3…) are the same shape.
So you can photocopy an A4 document onto A3 paper expanding it by the right proportion and it’ll fit perfectly. And you can copy two A4 documents onto A3 paper and it’ll fit perfectly. Or use psnup to put A4 formatted documents reduced to 2-up on A4 paper with no wasted space.
Try that with letter or legal size….
Things I learned:
On bra sizing, from ZeLonewolf:
The number is the measurement below the bust.
An A-cup is a 1-inch difference between the measurement below the bust versus around the bust. B-cup is 2 inches, C-cup is 3 inches, etc. DD is the same as E, DDD is the same as EE which is the same as F. This holds valid through an H cup. After that, the interval is 2 inches, with the doubled letter being the in-between value. Thus, H-cup is 8″, and I-cup is 10″, and a 9\” difference would be an HH-cup.
The largest bra size manufactured without a special order is a size 60N.
On the origin of “one for the road” and “on the wagon”, from Sirch:
Not quite. The saying actually refers to the trip from the prison to the Tyburn Tree in London. The prisoner to be hanged would be given drink to calm him down for the hanging. The closest pub to the place of hanging that lay upon the route was a mile away. The prisoner would have a drink at this last pub, and then be given a drink to have on his way to the gallows. Interestingly, this is also the origin of “on the wagon” as one of the guards travelling with the prisoner was not allowed to enter the pubs with him. So couldn’t drink, and had to stay on the wagon.
Three posts on the pros and cons of metric and US measurements as applied to construction, from barawn, SamSim, and mamahuhu:
That’s not quite true – one of the reasons that the Imperial system is moderately convenient for building is that base 12 is divisible by 2,3,4 and 6, so you’ll encounter less rounding error if you need to split things up into common numbers. Base 10 is only divisible by 2 and 5. (Incidentally, this is of course why one of the older civilizations used base 60 – it’s divisible by 2, 3, 4, 5, and 6, and it’s the reason we have 60 seconds in a minute, 60 minutes in an hour).
So, for instance, if you want to break a 1′ object into thirds, you can do it exactly. Try doing it with meters – it’s 33 and a third centimeters. Most people would say “screw it, it’s 333 mm” – but if you now take those “1/3 m” sticks and put 300 of them end to end, you don’t have 100 m – you have 99.9 m, and you’re a full ten centimeters short. In imperial, 1/3 of a yard is 1 foot. No rounding errors.
There really are advantages to the Imperial system – most people, however, simply assume that Imperial sucks and leave it at that.
I would have infinitely greater respect for the Imperial system if all of it did indeed work in twelves, like with feet and inches. But inches are not divided into twelfths but sixteenths. Then there are three feet in a yard, 5.5 yards in a rod, 40 rods in a furlong, 8 furlongs (or a nice round 1760 yards) in a mile. 16 ounces in a pound, 14 pounds in a stone, 2000 pounds in a ton. Don’t get me started on liquid measure. And ultimately, you have to measure so closely that you have to use decimal places of the smallest unit (like 11.6 inches or whatever) – which means tens all round.
Remind me again what makes it easier to use?
Just go with tens. Tens are simple.
I’m an architest and I can tell you that the Imperial system sucks big time and is not convenient at all.
Adding up Imperial measurements is a freaking nightmare.
In the rest of the world we use standard sizes for construction materials like 150x150mm wall tiles, 300×300 floor tiles, 600×600 raised floor tiles, 900×900 carpet tiles, 1200×2400 (or higher) gypsum wall panels…. get it – it’s all on a sensible module that you can use to line everything up on …. AND it doesn’t stop you from use the exact same convenient divisor of base 12. In fact the above building material sizes show this exactly.
And you can easily add them all up.
The other thing that no one has mentioned is scale and the A system.
The majority of drawings we make are A1 sizes – which nicely scales to A3. A 1:50 drawing at A1 becomes a 1:100 scale at A3 – not the freaking ridiculous Imperial scales.
Then you can get a ruler with a 1cm scale on it and every cm is a metre.
Note that if you scale a A3 to A4 then everything becomes an inconvenient scale. What happens is that you reduce A3 to A4 for a Fax transmission the receiver scales it back up to A3 to use.
Note that the same issue occurs with A1 to A2 or A2 to A3. You need to scale down two levels in the A system to maintain scale – which is fine for most uses.
So the Imperial system sucks in all ways for Architects and construction in general.
On scaling in-progress engineering drawings, from the linked article, pointed out by Momomoto:
Technical drawing pens follow the same size-ratio principle. The standard sizes differ by a factor sqrt(2): 2.00 mm, 1.40 mm, 1.00 mm, 0.70 mm, 0.50 mm, 0.35 mm, 0.25 mm, 0.18 mm, 0.13 mm. So after drawing with a 0.35 mm pen on A3 paper and reducing it to A4, you can continue with the 0.25 mm pen. (ISO 9175-1)
Things I laughed at:
On good uses for US size paper, from ajs:
Also, if you take 3 8.5×11 sheets, line them up along their longer sides, attach them to eachother, put a staple through the middle of the first and second sheet join and then hang them from a height of approximately eye-level it makes the idea place for a picture of a naked “girl next door”.
My buddy Heff taught me that trick.
Two posts on combining two A4s, from Anonymous Coward and Golias:
There’s also an Audi A4, and if you put two of those side by side, people say “Look, isn’t that a coincidence”.
Two Mini Coopers side by side == One Audi A4 Two Audis == One BAM (“Big Assed Mercedes”) Two Mercedes == One average European house.
Wow, those Europeans can apply simple metric system math to everything!
Meanwhile, in America: Two Mini Coopers side by side == One speed bump for a Hummer H2. Two Audis in the driveway == A good house to break into. Two Mercedes == Really, really tacky. Two Hummers == The energy consumption of a typical third-world country Two third world countries == A re-unified Germany. (I keed!)
On the real reason why the US will never switch, from forrestt:
Actually, it has to do with apple pie. Since there is nothing more American than apple pie, the apple pie recipe is considered sacred. It has been passed down from generation to generation since the start of this glorious nation. Unfortunatly, it has been passed down on the female side of our ancestry, and we men have been telling our women that:
|——| = 10 inches, when in fact |———| = 10 inches.
This has caused them to become totally confused with regard to units of measure, and they are thus unable to convert imperial to metric units. Thus, if we were to switch to using the metric system, we would no longer be able to bake apple pies, a situation we are just not willing to accept.
On Japanese influence over metric paper sizing, from revery:
And of course, 5 sheets of almost any metric sized paper folded into origami lions will inevitably merge to form Voltron, a robot so powerful that it will usually let it’s enemies kick it’s butt around for a good 15 to 20 minutes before it forms the blazing sword and finishes the fight.
