What is the lubricant used when tapping?

When tapping, a common lubricant used is cutting oil, which helps reduce friction and heat, prolonging tool life and improving finish quality. Other options include water-soluble oils and synthetic lubricants, which can provide cooling and lubrication. The choice of lubricant often depends on the material being tapped and the specific application requirements. Proper lubrication is essential for achieving clean threads and preventing tool wear.