Wood Shrinkage Calculator
Dimensional Change
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New Dimension
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Percentage Change
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Understanding Wood Movement
Wood expands and contracts with moisture changes. Tangential shrinkage (flat-sawn) is about twice the radial rate (quarter-sawn).
Typical rates: tangential 0.35-0.40% per 1% MC, radial 0.18-0.22%, longitudinal under 0.02%.
Wood moves only below fiber saturation (~25-30% MC). Indoor furniture equilibrates to 6-9% MC depending on climate.
Frequently Asked Questions
Why does quarter-sawn move less?
Growth rings perpendicular to face means radial shrinkage (half of tangential) dominates.
Target moisture content?
Indoor furniture: 6-8%. Outdoor projects: 12-15%. Acclimate wood to its environment before working.
How to account for movement?
Use floating panels, elongated slots for breadboard ends, slotted screw holes for tabletops.
Does finish stop movement?
No finish stops it completely. Film finishes slow it; penetrating finishes slow it less. Finish both sides.