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Drill Troubleshooting Chart

Problem Cause Solution
Heavy Wear at Outer Edge
  • Incorrect speed & feed
  • 1, 2, 8
Chipping at Outer Cutting Edge
  • Loose tool, tool movement
  • Workpiece movement
  • Incorrect speed & feed
  • 8, 10, 11, 12, 14, 16, 17, 21
  • 8, 12, 13, 21
  • 1, 2, 3, 4
Drill Point Chipping
  • Loose tool, tool movement
  • Incorrect speed & feed
  • Drill centering
  • 10, 11, 12, 14
  • 1, 2, 3, 4
  • 8, 10, 11, 12, 21
Margin Wear
  • Drill margin rubbing wall
  • Poor chip evacuation
  • Workpiece movement
  • 20 (check drill for backtaper)
  • 5, 6, 8, 20
  • 8, 13, 21
Tool Breakage
  • Loose tool, tool movement
  • Workpiece movement
  • Wrong drill type
  • Incorrect speed & feed
  • 8, 10, 11, 12, 14, 16, 17, 21
  • 8, 12, 13, 21
  • 9, 15, 16, 18, 19, 20
  • 1, 2, 3, 4
Poor Tool Life
  • Incorrect speed & feed
  • Wrong drill point
  • 1, 2, 3, 4
  • 8, 21
Drill Walk
  • Incorrect speed & feed
  • Tool wear
  • Wrong drill point
  • Material condition
  • 1, 2
  • 7, 8, 21
  • 8, 10, 11, 21
  • 11, 12, 15, 16, 17
Chip Welding
  • Wrong drill type
  • 19, 20
Hole Size Inaccuracy
  • Incorrect speed & feed
  • Loose tool
  • Wrong drill type
  • 1, 2, 3, 4
  • 14
  • 9, 18
Non-Cylindrical Hole
  • Loose tool, tool movement
  • Workpiece movement
  • Incorrect speed & feed
  • Wrong drill type
  • 8, 10, 11, 12, 14, 16, 17
  • 13
  • 1, 2
  • 18, 21
Heavy Burr
  • Incorrect speed & feed
  • Incorrect drill point
  • 1, 2
  • 8, 21
Blue Chips
  • Tool wear
  • 7, 8
Long Chips
  • Poor point grind
  • Incorrect speed & feed
  • 8
  • 1, 2

Solutions Key 1) Reduce RPM
2) Increase feed
3) Increase RPM
4) Reduce feed
5) 
6) 
7) Add negative hone
  8) Repoint drill
  9) Correct drill type/size
10) Use self-centering drill
11) Spot/center drill
12) Clean surface
13) Improve rigidity/clamp
14) Tighten holder
15) Use straight flute
16) Use stub length
17) Place further up holder
18) Use three-flute
19) Use slower helix
20) Use parabolic design
21) Change point style