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The Natural Philosopher The Natural Philosopher is offline
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Default Seasoning Wood in a Cellar

wrote:
A bit of science:

http://en.wikipedia.org/wiki/Seasoning_%28wood%29

Not bad, but it does miss one point: That not only will you get
splitting due to differential drying, but the rate of expansion and
contraction of the wood is radically different between three axes -
along the grain, radially from the heartwood and tangential to the bole
circumference.

A thin cross section of a trunk will ALWAYS suffer radial cracks no
matter how carefully it is dried unless the water content is held high
by soaking the wood in some form of water retaining or water replacement
chemical.

This actually presents the wood processor with real problems. Thin
sheets will dry faster, without splitting, but may end up warped on
drying. And cannot be made to bigger sections thereafter. Ultra thick
sections will crack anyway regardless of the drying regime.

One appreciates why so much wood ends up as pulp or chipboard..the
wastage is pretty massive. The wood processors I have spoken to, reckon
on about 40% wastage in most bulk bouht timber, for one reason or another.


I was not aware of the property changes in dried wood, except in a crude
subjective way: green oak works much easier than dry, and green willow
splits more easily than dry.

I had also not appreciated the sterilization effects of kiln drying.

And, whilst extremely informative, it didn't really answer the question
of "how long and how much ventilation?"

The very best book I have found on wood as an engineering material is
'Understanding Wood' by an America Author - Hoadley.

I must replace my copy. I gave it to the carpenters who built my house..

It's an absolute must for anyone doing more than nailing softwood
together for frames..