The best coolant for a CNC machine is the one that works best with the machine, the material you're cutting and your budget. There are many different coolants on the market each with their own advantages and disadvantages
The question of which coolant is best depends on what you want to achieve with your machine. The most important thing is to choose a coolant that has high resistance to heat and chemicals. The type of plastic you're cutting also affects your choice of cooler.
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