Notes

2 flute or 4 for aluminum end mill
Milling machines are designed with a built-in spindle to hold a type of cutting tool called an end mill. These end mills can be used to carve out grooves, slots, and pockets and carry out cutting, contour milling, and face milling operations. They come in two distinct varieties depending on whether they possess one or more flutes in their design.

End mills that are fluted are great for milling, drilling, and cutting slots, pockets, and grooves into a material. The flute is the area of the end mill that is responsible for performing the cuts and, generally speaking, the more flutes present, the better the End mill will be at warding off those cuts. Unfortunately, this also means that it is more prone to being damaged or broken much quicker due to its fragility.

When https://www.mskendmill.com/HRC55-Aluminum-Cutting-Tools-End-Mill-pd40331021.html as aluminum, plastics, and composites that can be easily destroyed and warm up quickly, four flute end mills are the tool of choice. This is due to their ability to maintain the integrity of the material under the high speed and temperature required for the cutting process.
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