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Dowels are sized by diameter, and round over bits by the radius, so for a 3/4" dowel you need a 3/8" round over bit. For example: CMT 838.222.11 3/8'' Radius X 1/2'' Cutting Length 2-Flute Rou
I haven't made dowels, for a 3/4" dowel I'd expect you'd use a 3/4" square piece.
Dowels are sized by diameter, and round over bits by the radius, so for a 3/4" dowel you need a 3/8" round over bit. For example: CMT 838.222.11 3/8'' Radius X 1/2'' Cutting Length 2-Flute Rou
I haven't made dowels, for a 3/4" dowel I'd expect you'd use a 3/4" square piece.