PS: I watched both videos, Mr. Smith. He's does a great job explaining and experimenting. (In fact, I wouldn't have felt like moving all that lumber round to put the load on the 4 pieces - maybe some other way?) He doesn't go through any theory. Such theory would involves what he calls "tension", but more correctly is residual stress in the wood. I guess lumber that is water-soaked has these stresses relieved, with different "bonds" of some sort being made during drying in the flat condition vs drying when still warped.

That was fun stuff - it's great to see people with such interest put that time into it.

One thing though regarding the wood I've got. I've seen different wood out West that is called pressure-treated than the pressure-treated stuff we get, with that chemical smell.* I don't know if anything the lumber guy in those videos found out would apply to the PT wood. He's using untreated wood obviously, as (I assume) he milled that all out of logs himself, shown in previous videos.

All the soaking won't work, I don't think, as the whole point of the PT is to fix it so water doesn't penetrate far. There must be a lot of chemical in them too, because the weight difference is significant. (I should cut off pieces short enough to weigh and determine this sometime.)

Here's a great video, something of an advertisement, but still with a great explanation of pressure treatment of lumber - one could read the page too if he doesn't want to watch the ~ 5 minutes.

https://www.treatedwood.com/learn/how-wood-is-treated


* Ahaa, from the video I'm about to mention, that's called incising (03:22) and that's done for Douglas Fir, so I guess that's the wood I was seeing.

PS: Good afternoon, Mr. Moderator & Friends,

Crooked Lumber? This is just one example of why it (may?) make more sense to build with steel.

But, the good news is that you can straighten that crooked lumber...

https://www.youtube.com/watch?v=Q6ksn64IcS4
https://www.youtube.com/watch?v=OCJxVQ07IJk

Happy Saturday! ☮️

PS: Haha, definitely not those - birch? Yeah, this is usually yellow pine, and It's not as warped as that forest, I found about a 1/2 - 3/4" deviation on the 1 1/2" edge (i.e., off in the width direction) in the middle of a 16 footer. Flipping them around to match each other helped, but there's no getting that out of there easily, as one can do with warpage in the other dimension.

That's not so bad, but it was really the 4 x 4's with the problem. One, when laid on the ends on the flat/level concrete was 4" off the ground in the middle of the 12 foot length. I can't say for sure those are yellow pine though. (Treated 4 x 4's)

PS

Maybe you should use spruce, fir, or pine.