Tool Bit Selection TipsFind the Best End Mill or Engraving Tool for your Application and Material Superior Quality, Solid Carbide Tooling – Manufactured In House Which Engraving Tool to Use? Assistance with choosing which style of Engraving Tool to use for a specific application. Which End Mill to Use? Assistance with choosing which type of End Mill to use for a specific application. What is a Smart Part Number? Part Number break-down for Engraving Tools, End Mills and Cutting Tools. Custom Tooling We manufacture Custom Tools in house. Here are some forms for helping describe your custom design to us. Inches to mm Reference Table Convert Inches to Millimeters. Convert Millimeters to Inches.