Rich

Wood still moves radially.  It's less than tangential movement, but it is a factor.

Hi Rich. this is why I will always use QS WO, or Hard Maple, both will move very little, if at all. You will see that tangential movement a lot more with softer woods of the hardwoods, and almost all of the softwoods.

Good to point out though, as wood choice here will effect result greatly

I think those forefather guys heading West all those years ago, and their predecessors who in Europe, and elsewhere used and tried all manner of trees for different jobs to figure out which were the best performers. I imagine a lot of trial and error went into that knowledge base.

Maybe the biggest reason I like the Wood Database so much. Each listing for every species/variant has a section showing what it is good for as far as uses. Strengths, and weaknesses so to speak.

WO

Likely you won't find a wood listing saying makes killer table saw sled runners, but if a wood is listed as being strong in the flooring market, then it will be stable as a runner. Especially if a QS section is used, and correctly positioned.