Jointers

A jointer flattens one face or squares one edge of a board with a spinning cutterhead. The cutterhead is open on the table, so the hands are close to sharp knives. Jointers cause serious hand injuries when guards are removed or small pieces are used.

• Woodworking
• Cabinet Shops
• Home Shops

Parts you should know

• Infeed and outfeed tables, which set the depth of cut and keep the board flat.
• Fence, which keeps the board square for edge jointing.
• Cutterhead, with knives or inserts.
• Guard, which covers the cutterhead and moves out of the way as the board passes.

Hazards

• Hand contact with the cutterhead, especially when passing over the end of a board.
• Kickback if the board catches or the knives are dull.
• Noise and dust. Wood dust is a health and fire hazard. See Wood Dust.
• Flying chips and loose knives.

Safe operation

• Keep the guard in place and working. Check that it springs back to cover the cutterhead.
• Use push blocks or push pads to hold the board down on the table and move it through. Never let your hand pass over the cutterhead.
• Set a light depth of cut, usually 1/16 inch or less.
• Feed the board against the rotation of the cutter, with the grain running as the maker advises.
• Use stock long enough and thick enough to control safely. Many shop rules say do not joint boards shorter than about 12 inches or thinner than about 3/4 inch; check the manual.
• Wear eye and hearing protection, and a dust mask or respirator as needed. Tie back loose hair and clothing; no gloves near the cutterhead.
• Use dust collection and keep the floor clear of chips.

• Do not joint very small pieces, warped boards with loose knots, or boards with nails.
• Do not make cuts that remove material while your hand is at the cutterhead.
• Do not clean or adjust until the cutterhead has stopped and the machine is unplugged.

Last updated: October 8, 2026