Anatomy of an Endmill
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Length of Cut - The length the endmill is able to cut. This is not equivalent to flute length.
Neck - This is the portion of the endmill that can rub on the material as the flutes cut during a deep cutting operation. It includes both the top portions of the flutes not suitable for cutting. A necked endmill has a portion of the length above the flutes at a smaller diameter to give it a deeper reach. Necked endmills aren’t the typical style, but they are an option if required.
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