🔍 Key Concepts

• Tooth-per-inch (TPI) selection for different metals (hard vs soft) when using a hand hacksaw • Proper blade orientation (direction of teeth) on a standard hand hacksaw frame • When coolants/lubricants are normally used in hand sawing of metals like brass

💭 Think About

• Think about what happens if you use a very coarse blade (few teeth per inch) on hard, thin material. Will it cut smoothly or tend to snag and break teeth? • On a traditional hand hacksaw, do you cut mainly on the push stroke or the pull stroke? How should the teeth face for that stroke to do the cutting? • Is brass usually cut dry or with coolant when using simple hand tools like a hacksaw, and why might coolant be used or avoided?

✅ Before You Answer

• Verify which materials usually need fine teeth (higher TPI) versus coarse teeth (lower TPI) for safe, smooth cutting. • Confirm the normal cutting stroke direction for a hand hacksaw and match that with the correct tooth direction on the blade. • Consider whether using coolant on brass with a hand hacksaw is standard practice or only used in special situations.