Milling rough lumber four-square

Let rough lumber sit in your shop for a few days before you cut it, and after rough-cutting parts, stack them with spacers so air reaches every face and the stresses released by cutting can settle before you mill them to final size.

Two sources: Fine Woodworking (Taunton Press) and Woodcraft [source 1, source 2]

Cut parts to rough length and width first, oversize, and mill them to final size last.

Two sources: Fine Woodworking (Taunton Press) and Woodcraft [source 1, source 2]

Rough hardwood is sold by its rough thickness in quarters of an inch: 4/4 is 1 in, 8/4 is 2 in. Surfacing removes some of that; the hardwood thickness chart lists what each quarter planes down to by the lumber rules, and the board foot calculator counts a board at its rough size.

Arithmetic: exact by definition

Flatten one face on the jointer. With that face down on the planer bed, plane the other face flat and parallel to it, to the thickness you want. Joint one edge square to the first face, rip the other edge parallel to it on the table saw, and finally crosscut the ends square and to length.

3 sources agree [source 1, source 3, source 2]

Read the grain before each pass and feed so the knives cut with it. Mark the feed direction on the board so you don’t have to work it out again.

Two sources: Popular Woodworking and Woodcraft [source 3, source 2]

DeWALT describes snipe as a deeper cut at the ends of a board, made when an unsupported end drops and tips the other end up into the cutterhead.

One source: DeWALT, the maker of that planer [source 4]

Support long boards level with the planer bed going in and coming out, with extension tables or rollers.

3 sources agree [source 4, source 5, source 6]

OSHA requires push sticks or push blocks for jointers (29 CFR 1910.213(s)(12)).

One source: OSHA, the federal standard [source 7]