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Wood shrinkage estimate

Estimate green-to-dry cross-grain shrinkage using a species and radial or tangential coefficient.

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Example inputs · U.S. customary units

A white-oak tangential shrinkage example. Confirm the species, direction, coefficient and moisture assumptions; individual boards vary.

Example: 12 in.

Example: 10.5 %.

Example: 12 %.

Example: 30 %.

Results

Ready to calculate

Enter your values, then choose Calculate. Your results will appear here.

How to use wood shrinkage estimate

What this calculation does

A linear shrinkage estimate scales an entered green-to-oven-dry coefficient to a target moisture content below fiber saturation.

Choose a coefficient that matches species and radial or tangential direction, then enter the green dimension and target condition.

Enter the measurements

  1. Green dimension: Measure the starting green dimension.
  2. Green-to-oven-dry shrinkage: Enter the matching green-to-oven-dry coefficient.
  3. Target moisture content: Enter the target moisture content.
  4. Fiber-saturation assumption: Enter the fiber-saturation assumption used.

Formula and variables

Sx = S0 × (1 − target MC / fiber saturation MC); final = green dimension × (1 − Sx/100).

Estimated shrinkage = S0×(1−target MC÷fiber saturation MC); final dimension = green dimension×(1−shrinkage percent÷100).

Read the result

With the stated 10.5% coefficient, 12% target MC and 30% FSP, estimated shrinkage is 6.3% and final dimension is 11.244 in.

Worked example

Inputs: 12 in white oak tangential; S0=10.5%, target MC=12%, FSP=30%

  1. Shrinkage = 10.5×(1−12÷30) = 6.3%.
  2. Final dimension = 12×(1−6.3÷100) = 11.244 in.

Expected result: 6.3% shrinkage; 11.244 in final

Frequently asked questions

Is the default coefficient universal to white oak?

No. The selected value is an illustrative species and direction coefficient; boards vary.

Does the estimate cover movement above fiber saturation?

No. This linear model is restricted to a target below the entered fiber-saturation value.

Conditions, presets and technical notes

This is an average linear estimate below fiber saturation. S0 must match the species and radial or tangential direction. Defaults illustrate white-oak tangential shrinkage, not a universal coefficient. Individual boards vary.

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