I hope it’s not against the rules here, just saw this woodworking related xkcd that I enjoyed and thought it might be appreciated here:)
Have you hard of our lord and savior, the metric system?
We have but Canada sells so much construction supplies to the US that we don’t use metric for it.
???
Even metric is under-sized on dressed timber 4x2" ~ 100x50mm => 90x45m dressed
Yeah, but then we just use the 90x45mm as a measurement…
Also if I remember correctly it’s sold as 89x44. 45mm was only used for I-joists
Wait 2×4s are not 2×4?? What is wrong with americans??
They were 2x4 before drying the wood (that’s what I heard)
You heard wrong. They use excuses like that, but truth is they can make the final size anything they want, for many years every different sawmill decided their own final size. You start by cutting wet wood to a size, you might or might not dry it, then you plane it down to an exact size. Some sawmills started by cutting to 2x4 and then planning different amounts off. Others cut bigger so when they planed it down they finished with 2x4. Everyone did something different and so if you bought a 2x4 you better pray that sawmill remains open for when you want to remodel and need more. Eventually enough people got sick of this and decided to make a standard, the current measurements are what was decided, it was arbitrary, but at least everyone follows the same standard so you can buy from different sawmills. Exactly 2x4 is also arbitrary.
Or they could have just decided that “arbitrary” factor to be 1.
But oh wellI wish they had, but at least there is a standard, which is far more important.
They shrink?
And expand 😘
They are until they’re planed to smooth them, at which point they are approx 1.5" x3.5"
Just like 50x100’s are usually more like 40x90’s, or something even more insane - 39x86? Like I’m sorry, but the unit of measurement is NOT the problem, it’s the centuries old “traditions” and “standards” to normalize dimensional lumber that are the problem.
At any rate, one should look at the names of boards as the ratio of their dimensions and leave the inches and mm out of it and it starts to make more sense.
They always have the exact measurements here like 200 x 5,8 x 3,8 cm
Except that all of the board length measurements will not work out.
A nightmare if you’re following written measurements or working with other people, but as long as you use the same tape to measure how much you need and how much you have/are cutting, it should work out alright.
Damn creative measuring.
Twin Peaks on 2x4
