Basic Facts On Drying Lumber

Why Dry Lumber?

Fresh cut lumber contains a great deal of water. If not removed, the lumber can't be used to produce high quality finished product. Properly dried lumber sells for a higher price and much easier to work with than lumber that has not been dried. When lumber is dried right, it machines better, glues better, and finishes better.

Drying improves the the strength, kills infestations, hardens pitch, preserves color, reduces weight and controls shrinkage.

When lumber is not dried under controlled conditions its prone to damage, warping, staining and diminished sales value.

How much water is in lumber?

A Lot. In Fact, some species of wood are more than half water in terms of their weight when freshly cut. A truckload of green lumber is about 22 tons. A truckload of dried lumber is about 14 tons-- that's 8 tons of water !

Benefit to you-

1.Reduced cost in shipping

2.Better Quality wood

3.Better Quality of goods produced

 

Once wood is dry will it remain dry?

Wood is always trying to come into equilibrium with the air surrounding it, so its moisture content can change somewhat after it's been dried.

Can drying cause the wood to split or check?

Wood does shrink as it dries, but the shrinkage doesn't start until the lumber is below fiber saturation, about 28% moisture content. If the outside surface is below 28% while the center of the board is still above fiber saturation, the outside will try to shrink while the center doesn't- and if this continues, until the surface becomes too dry in relation to the core, the lumber will split or check.

Does the thickness of the lumber affect the drying rate?

Generally speaking, drying times are roughly proportional to the thickness.

Can pitch be set in pine?

When softwoods are dried, pitch sets at whatever the final temperature of the drying cycle. For example: if the the last step in drying was 120° F. (49° C.) than the pitch won't run unless the wood is heated above 120°F. The furniture industry usually expects pitch to be set at 160° F. (72° C.).