Walt Davis's List: Machine Shop Essentials

• less room for swarf
• less material removed per flute
• More flutes allows a higher feed rate
• Flutes:
• • Helix angle:
• High helix angles are typically best for soft metals, and low helix angles for hard or tough metals

4 more annotations...

• plug tap:^[4]
• Bottoming tap
• continuous cutting edge with almost no taper
• cut threads to the bottom of a blind hole
• used to cut threads in a hole that has already been partially threaded
• has tapered cutting edges
• most commonly used type of tap
• plug

6 more annotations...