Heat is a big concern when machining metal. Heat buildup can destroy the workpiece, create dimensional problems, and shorten the life of the cutting tool, which is why machining operations generally use some type of cooling fluid during the process.
In high-speed machining, the heat is dissipated into the chip, so the chips need to be separated from the workpiece, leaving minimal heat in the work piece. Flood cooling is often used for large depths of cut to remove the hot chips from the workpiece. "In some situations, machinists still use liquid coolant or mist, which aids in the lubrication process but doesn't get the chips out of the way, so we recommend that people use liquid coolants on finishing pieces - it doesn't cool anything down but offers lubricity," said Walter Stuermer, sales manager for Millstar, a maker of precision milling tools.
Stuermer notes that there is a whole range of issues surrounding cooling fluids, pointing to "the whole environmental factor" as one major one. Additionally, he said, "It's messy. There's the cost factor - not just for the fluids but it adds maintenance because it's more difficult to keep the interior of the machine clean. It stinks. And it's harder to see what's ...