I have noticed that most(well over 90%) of the twisted lumber I see twists the same way.
(I recently stacked about 200 14' and 16' long 2x4s and 2x6s, and of the 50 or so that were twisted, only one twisted the opposite way--and that one had a lot more grain runout than normal)
As I look down the length of a 2x4, it will twist anti-clockwise as it goes away from me, or conversely, seem to twist clockwise as it comes toward the viewer.
Northen hemisphere cyclones (low pressure domes) twist anticlockwise as you look down on them.
Southern hemisphere cyclones (low pressure domes) twist clockwise as you look down on them.
While winds around high pressure domes move clockwise.
so looking "down" on the 2x4 that came from a northern hemisphere forest, it seems to mimic the pressure pockets of our hemisphere.
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coincidence? or causality?
..........
So, the question obtains:
Does timber harvested from southern hemisphere forests tend to twist in the opposite direction of northern hemispher's lumber mimicing or caused by the same mechanism governing cyclones and pressure domes?
Any of you southern hemisphere guys notice the twist in lumber from your hemisphere?
and which way does it twist?