🔍 Key Concepts

• Properties of cast iron when being cut (brittle, produces small chips) • Purpose of cutting lubricants: cooling vs lubrication vs chip removal • When it is acceptable or even preferable to cut dry without lubricant

💭 Think About

• Think about how cast iron behaves when drilled: does it tend to gall and smear, or break into small chips? How does that affect the need for lubrication? • Ask yourself: which of these fluids would interact with cast iron chips and dust in a way that could cause problems like mud, clogging, or smoke? • Consider whether the main problem with cast iron drilling is heat buildup, friction, or something else—and which option best addresses that.

✅ Before You Answer

• Verify what type of chips cast iron makes and whether they need flushing away with liquid or tend to fall clear on their own • Check which of these fluids is commonly avoided on cast iron because it forms an abrasive slurry with the dust • Confirm whether common machining practice for cast iron is to run dry or with heavy lubrication