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SESK: Stuff Everyone Should Know · sesk.info/wood-jointer-knife-projection

OSHA says jointer knives must not project more than how far past the cylindrical head body?

No more than one-eighth inch.

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  1. One inch
  2. One-eighth inch ✔
  3. Three-quarters inch

Why: A knife that sticks out too far takes a bigger bite and increases the risk of kickback and contact. OSHA 1910.213(j)(1) limits projection to one-eighth inch beyond the cylindrical body.

Huh, didn't know that: The table opening must also be kept as small as possible under (j)(2).

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Why did the evil queen order her subjects to cut down all the trees in the kingdom? She was jealous because every one of them had a bigger crown than her.
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References

Answer: One-eighth inch. A knife that sticks out too far takes a bigger bite and increases the risk of kickback and contact. OSHA 1910.213(j)(1) limits projection to one-eighth inch beyond the cylindrical body.

  1. OSHA 29 CFR 1910.213 Woodworking machinery requirements www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.213
    the knife projection of which shall not exceed one-eighth inch beyond the cylindrical body of the head
    Checked 2026-10-10.

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