Definition
Lumber cut from a log so that the annual growth rings meet the wide face of each board at an angle of 45 degrees or more, ideally close to 90 degrees. Quartersawing produces wood that is more dimensionally stable, less prone to warping or cupping, and stronger across the grain than wood cut by the more common plain-sawn (flat-sawn) method. It is the preferred cut for wooden aircraft structural members such as wing spars and propeller laminations.
Plain English
Wood cut from a log in a way that makes the growth rings run nearly straight up and down through the board, rather than in long curves across the face. This cut produces stronger, more stable wood that holds its shape well over time.
Context Anchor
Seen in aircraft wood structure inspection, repair, and material selection, especially for wooden spars, ribs, and other structural pieces.
Derivation
The term comes from the sawing method: the log is first split into quarters lengthwise, then each quarter is sawn into boards. Cutting from a quartered log naturally produces boards with the rings running edge-to-edge rather than face-to-face, which is what gives the wood its characteristic strength and stability.
Why Pilots Care
Quartersawn wood resists warping and shrinking, keeping wooden airframe parts and propellers dimensionally stable under changing temperature and humidity.
Intuition Check
Quartersawn does not mean the board is simply one fourth of a log. Here it means the board was cut so the tree rings run mostly vertical through the board.
Example Sentence 1
The wing spars on the vintage trainer were built from quartersawn spruce to give them the strength and dimensional stability needed for flight loads.
Example Sentence 2
When shaping a replacement propeller blade, the shop used quartersawn wood to maintain balance in all weather conditions.