3 ms·

I genuinely hate that I'm going to say this, but... A 2x4 is 1.5" X 3.5" It's not _approximately_ 2x4 or _slightly_ smaller than 2x4. Not that this

I genuinely hate that I'm going to say this, but... A 2x4 is 1.5" X 3.5" It's not _approximately_ 2x4 or _slightly_ smaller than 2x4. Not that this adds critical information regarding the article, but if you set out to work with 2x4s and assume they are 2" by 4", you'll be sorry. And yes, I have made that mistake before, but it's a mistake you only make once.

c22 9y ago
The lumber is cut to 2" x 4", but then it is dried causing it to shrink to "about" 1.5" x 3.5"
- unwind 9y ago
  Wikipedia's page on lumber[1] is a bit more rigid: Today, a "2×4" board starts out as something smaller than 2 inches by 4 inches and not specified by standards, and after drying and planing is reliably 1 1⁄2 by 3 1⁄2 inches (38 mm × 89 mm). 1: https://en.wikipedia.org/wiki/Lumber#North_American_softwoods https://en.wikipedia.org/wiki/Lumber#North_American_softwood...
- birken 9y ago
  This is not correct. The standard construction 2x4 you buy at any lumber yard/home improvement store is specifically cut to 1.5" x 3.5". Of course wood naturally expands/contracts depending on the environment so it will never be exactly those dimensions, but quite close (+/- 1/32" I'd wager). Likewise with plywood, most (but not all) plywood sold in the US is actually slightly undersized. 3/4" is normally 23/32" thick, 1/2" is normally 15/32" thick, etc. This isn't because the wood shrunk (though again plywood will slightly expand/contract depending on the moisture of the environment), it's because the manufacturers meant it to be a little thinner. There are still manufacturing tolerances for both types of products, but the lumber mills know what they are doing, they know what their customers require and provide tolerances that match those. Just imagine one very common usage: a deck. You think deck builders would be happy if the dimensional lumber wasn't a) very consistently the same thickness and b) very consistently the same width? Otherwise you'd have a very bumpy deck that looked pretty irregular.
jonsen 9y ago
I genuinely hate to go and measure my lumber but anyway I just did: Unplaned 2x5 measures exactly 2" x 5" Planed 2x3 measures 1 15/16" x 2 13/16" Planed 2x4 measures 1 7/8" x 3 3/4" I'm in Norway. Apparently it's country specific.
- jononor 9y ago
  In Norway construction lumber is usually specced in mm, e.g. 48x98mm, which is smaller than 2*4 inches. People still call it 2x4 though...

c22 9y ago

The lumber is cut to 2" x 4", but then it is dried causing it to shrink to "about" 1.5" x 3.5"

unwind 9y ago
Wikipedia's page on lumber[1] is a bit more rigid: Today, a "2×4" board starts out as something smaller than 2 inches by 4 inches and not specified by standards, and after drying and planing is reliably 1 1⁄2 by 3 1⁄2 inches (38 mm × 89 mm). 1: https://en.wikipedia.org/wiki/Lumber#North_American_softwoods https://en.wikipedia.org/wiki/Lumber#North_American_softwood...
birken 9y ago
This is not correct. The standard construction 2x4 you buy at any lumber yard/home improvement store is specifically cut to 1.5" x 3.5". Of course wood naturally expands/contracts depending on the environment so it will never be exactly those dimensions, but quite close (+/- 1/32" I'd wager). Likewise with plywood, most (but not all) plywood sold in the US is actually slightly undersized. 3/4" is normally 23/32" thick, 1/2" is normally 15/32" thick, etc. This isn't because the wood shrunk (though again plywood will slightly expand/contract depending on the moisture of the environment), it's because the manufacturers meant it to be a little thinner. There are still manufacturing tolerances for both types of products, but the lumber mills know what they are doing, they know what their customers require and provide tolerances that match those. Just imagine one very common usage: a deck. You think deck builders would be happy if the dimensional lumber wasn't a) very consistently the same thickness and b) very consistently the same width? Otherwise you'd have a very bumpy deck that looked pretty irregular.

jonsen 9y ago

I genuinely hate to go and measure my lumber but anyway I just did: Unplaned 2x5 measures exactly 2" x 5" Planed 2x3 measures 1 15/16" x 2 13/16" Planed 2x4 measures 1 7/8" x 3 3/4" I'm in Norway. Apparently it's country specific.

jononor 9y ago
In Norway construction lumber is usually specced in mm, e.g. 48x98mm, which is smaller than 2*4 inches. People still call it 2x4 though...