The horrors of wood shrinkage

Blocks of wood as side tables seem to be all the rage at the moment. But if you are paying good money for a solid “side-table”, the last thing you want is for the wood to split. Loss of water means that wood shrinks. Shrinkage generally takes a circular direction around the tree, the fibres of the outer rings contract together and clefts (or radial cracks) open up, as is shown quite clearly in the picture below. This is because the circumference of the wood (tangential shrinkage) shrinks more than the radius (radial shrinkage).

logSplitting

Block wood side-table, from a spa in Iceland. This might likely be a native species, and seems to be older growth.

The reality is, in blocks of wood, it is hard to stop this cracking occurring, unless you choose a wood species with a low tangential shrinkage factor, or one which has been properly seasoned, or if you’re lucky comes from old-growth (and reclaimed) lumber. Sure, to some cracks may add a level of character, but at the price they charge for these blocks ($250-400), how much character do you really want? Below are some worse-case scenarios of logs left outside for a 12-16 month period. Radial cracks from tangential shrinkage are always easy to see. Radial shrinkage manifests itself in a manner whereby the radius of the log is reduced, and the space between the wood and the bark increases, allowing the latter to fall off.

shrinkTangential

Radial cracks in elm and maple logs

 

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