[exDM69]

In addition to wood movement, there's another important factor when it comes to hobbyist woodworkers: accuracy.

With modern adhesives and precision machining like Mathias' work will make mighty strong joints even out of the simplest joinery method. A precision made box joint glued with wood glue is stronger than a finely made dovetail joint.

But when it comes to me bodging away in my garage with hand tools, that kind of precision is not going to happen. But historical "strong" joints like dovetails and mortises and tenons with wedges and drawbores are very forgiving joints and are quite strong even when they're not made to sub-millimeter accuracy. I can join a decent box with dovetails in about 30 minutes, put it together with a few drops hide glue and fill the gaps with sawdust and it'll work great.

But someone with a table saw and a simple box joint jig could join 10 boxes in the same 30 minutes it took me to make one.

[jdietrich]

Modern hand tool woodworking can match or exceed the accuracy of machine woodworking, albeit with a higher skill threshold. You can achieve very fine results with very basic tools. Machine woodworking is undoubtedly faster, however.

Tight tolerances are often completely counterproductive because of wood movement. Even with an impermeable polyurethane finish, you'll get significant seasonal movement. Effective fine woodworking is about designing to account for that movement - building drawer runners slightly undersized so they don't bind up, allowing door panels to float in the groove so they don't bow or split etc. One of the key skills of cabinet-making is developing an intuition for wood movement.

https://www.canadianwoodworking.com/tipstechniques/dealing-w...

[nemo44x]

What about torrefying the wood first? Wouldn’t this reduce the amount of movement in the wood?

[exDM69]

You can't really stop wood movement or even reduce the amount it moves. It can be slowed down a little with some finishes (then you have a "wood-plastic composite"). Kiln drying (do you mean this by "torrefying"?) will make the wood dry for a while, but when the temperature and (absolute) humidity will rise on the summer, the wood will absorb moisture from the air and expand and shrink again next winter.

[jdietrich]

Torrefaction (more properly, thermal modification) involves higher temperatures than kiln drying, causing chemical changes to the wood that result in permanently lower equilibrium moisture content and hygroscopicity. It improves the stability of wood and drastically improves the resistance of softwoods to decay, but it isn't a complete solution to wood movement. There is a significant tradeoff between stability and strength.

https://en.wikipedia.org/wiki/Thermally_modified_wood

[abakker]

It also changes the color, which in many cases is inappropriate for the project. However, if it were being painted I would definitely consider it. I bought some Torrefied ash recently - it's weird stuff. Kind of like working with toast instead of bread. the sawdust smells odd, too.

[nemo44x]

In the acoustic guitar world, torrefication has become popular for some guitars. The main idea is that the end result of the spruce (commonly used for top wood on an acoustic guitar) is closer to a piece of spruce that is many years old which affects the tone and "improves" it to some ears. The other benefit is the wood is less likely to crack which is an issue with acoustic guitars, especially in dry climates where humidification is an issue. Some say the wood is more resistant to cracking but more brittle in other ways which aren't too important to how an acoustic guitar applies tension. the main idea is the wood won't change with respect to humidity as much as untreated wood.

But yes, especially when luthiers started using this technique there were all sorts of issues with the end result in terms of superficial results/coloring. However, they've gotten better at this and now we see the wood being a bit darker but without all the other cosmetic issues from past years.

[kazinator]

> A precision made box joint glued with wood glue is stronger than a finely made dovetail joint.

To clarify, do you mean "than a finely made dovetail joint without glue"?

[exDM69]

No, I do not. According to the strength tests I've seen (and my experience with joinery reflects this), there is hardly any difference in strength between a box joint and a dovetail when done with equal precision and glued with modern glue, given that they have roughly equal amount of glue surface area. But a box joint is much easier to cut with precision on a table saw with a simple jig.

Dovetails aren't usually used without glue (or wedges). A tightly cut dovetail will stay together just fine without glue, but it has relatively little resistance against shear stress. A small bump can turn a square box into a trapezoid even with good joinery.

When I do dovetails, I use a small drop of glue on the long grain of the pins and tails. That's enough to keep it from trapezoiding and allows me to plane the joint flush.

[jimnotgym]

Plus the dovetail, mortice and tennon with wedges etc are still strong even after wood shrinkage has cracked the glue line. A simple glued joint just falls apart.