Pick Straight, Sound Lumber by Sighting Every Board

The Problem

The rack at the lumber yard holds straight boards and boards that will fight you for the life of the project, at the same price. For a house package — hundreds of boards delivered pre-strapped — you take what comes. For a deck or any project where you're picking each board, a few seconds of sighting per board filters out the ones that crack, rock, and telegraph through finished work.

The Technique

Sight down every board from the long end, in both planes — once across the wide face, once across the narrow edge. You're looking for five things:

• Crown — a rise along the narrow edge. Almost every board has some, and a slight crown is fine (frame with crowns all facing the same way). Reject boards where the rise is significant.
• Bow — the board curves along its wide face, shaped like a canoe. Reject.
• Twist — the board corkscrews, so its far end sits in a different plane than the near end; the creator's test is that it looks wrung out like a towel. The worst defect to frame with — reject on sight.
• Cup — read the end grain. An end-grain arc means the board will keep pulling toward a trough shape as it dries.
• Dead knots and splits — a dead knot (dark, loose, with a ring of bark) is a structural void, worst on the board's narrow edge where the cross-section is smallest. The creator's example board cracked through a dead knot just sitting on the shelf. Big splits disqualify a board the same way. Live knots — tight, light-colored, grown into the grain — are generally fine.

Wane — a missing edge where the board met the bark — is worth avoiding too, though it's cosmetic at small sizes.