Reply by MonteCristo

I’ve planed thousands of feet of knotty cedar without much of a problem. Occasionally a knot will become dislodged so you should watch for that and clear the debris right away. Knots are typically pretty darn hard, even with soft woods like cedar, so expect that to take its toll on the planer blades. IE they won’t stay sharp as long as if the wood were clear. Light cuts are also a good idea here.

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