Cutting/Milling Metal with the blackToe CNC Machine

Here's the thing: specifically with aluminum, this metal melts at approximately 1200 degrees Fahrenheit, and when you apply an end mill rotating at high rates (i.e. 13,000 RPM), the end mill will get really hot, and melt the aluminum during the milling process. Aluminum is a low melting metal. Compare this to steel, which melts at 2100 degrees Fahrenheit and some machinists will say that mild steel is easier to cut that aluminum simply because the end mill can mill at a slower feedrate and dig out the material. There are many ways to control the temperature of the end mill. First, and the most widely used method, is to pour a liquid on the end mill while the end mill is cutting. This is a special liquid that is combined with a cutting fluid to provide the best cutting efficiency. Second, the end mill can be sprayed with just a cutting fluid which is typically done by hand. Mark initially used Isopropyl Alcohol. Third, cold air can be directed to end mill. Mark uses this method, which uses a vortex system that sends -50 degrees Fahrenheit air from one end of the nozzle, and very hot air out of the other end. The final method is simply finding that right balance of depth per pass, spindle RPM, feedrate and end mill flute and helix angle to achieve dry cutting. This final method is actually desired by the manufacturing industry (** add source **).