I want to know what is good for the engraving and milling

The procedure for machining parts of a controlled engraving and milling machine is usually much more complicated than that of an ordinary machine tool. The process procedure used on an ordinary engraving and milling machine is actually just a process card. The working steps are often selected by the operator himself. And CNC engraving and milling machines generally use a high-speed electric spindle for processing, so a lot of heat will be generated during the processing. This needs to cool down the spindle, so is the CNC engraving and milling machine cooler by water cooling or oil cooling? Traditional engraving and milling machines generally use water cooling, which is easy to cause rust inside the spindle, and it needs to be used during use. Changing the water frequently is very troublesome. The cooling method of the water chiller is usually by the fan to cool, without the compressor, the temperature of the main shaft cannot be accurately controlled. The oil cooling method is different. It uses an industrial-specific oil cooler to control the temperature of the coolant inside, and achieves the effect of cooling by circulating in and out of the spindle. This method is beneficial to protect the main shaft from rusting, and the replacement cycle of the coolant inside the oil cooler is very long. Generally, it can be replaced once more than a year.