When choosing a cutting fluid, what primary factor must be taken into account?

When selecting a cutting fluid for machining operations, the compatibility with the material being machined is the primary factor to consider. This compatibility ensures that the cutting fluid efficiently lubricates and cools the workpiece and tool during the cutting process, which can help to improve tool life, surface finish, and machining accuracy. Different materials can react differently to various cutting fluids; for instance, some fluids may cause corrosion or may not provide adequate lubrication for particular metals.

Choosing a fluid that works well with the specific material being machined is essential for optimizing performance and preventing damage to both the material being worked on and the cutting tools used. While cost, color, and brand might play a role in the decision-making process, they are secondary considerations compared to the necessity for effective compatibility with the workpiece material.