Outer Corners Break Down
Cutting speed to high
Hard spots in material
No cutting fluid at drill point
Flutes clogged with chips

Cutting Lips Chip
Too much feed
Lip relief too great

Checks or Cracks In Cutting Lips
Overheated or too quickly cooled while sharpening or drilling

Margin Chips
Oversize jig bushing

Drill Breaks
Point improperly ground
Feed to heavy
Spring or backlash in drill press, fixture or work
Drill is dull
Flutes clogged with chips

Tang Breaks
Imperfect fit between taper shank and socket caused by dirt or chips
Burred or badly worn sockets

Drill Breaks When Drilling Brass Or Wood
Flutes clogged with chips
Improper type drill

Drill Splits Up Center
Lip relief too small
Too much feed

Drill Will Not Enter Work
Drill is dull
Lip relief too small
Too heavy of web

Hole Rough
Point improperly ground or dull
No cutting fluid at drill point
Improper cutting fluid
Feed too great
Fixture not rigid

Hole Oversize
Unequal angle or length of the cutting edges or both
Loose spindle

Chip Size Changes While Drilling
Drill becomes dull
Cutting lips chipped

Large Chip Coming Out Of One Flute Small Chip Out Of Other Flute
Point improperly ground
One lip doing all of cutting

Outer Corners Break Down-Solution
Decrease cutting speed
Increase Coolant flow

Cutting Lips Chip-Solution
Decrease feed rate
Decrease lip relief

Checks or Cracks In Cutting Lips-Solution
Decrease feed rate
Use coolant when sharpening

Margin Chips-Solution
Check to make sure proper bushing being used
Check bushing for size

Drill Breaks-Solution
Resharpen drill
Reduce feed rate
Check fixture
Check set-up

Tang Breaks-Solution
Wrong size socket
Worn sockets-Replace
Clean Sockets

Drill Breaks When Drilling Brass Or Wood-Solution
Reduce feed rate
Using wrong type of drill

Drill Split Up Center-Solution
Increase lip relief
Decrease feed rate

Drill Will Not Enter Work-Solution
Sharpen drill
Increase lip relief
Use different drill with lighter web

Hole Rough-Solution
Sharpen drill
Increase coolant flow
Reduce feed rate
Check rigidity of fixture

Hole Oversize-Solution
Sharpen drill
Check drill point for consistency
Tighten spindle

Chip Size Changes while Drilling-Solution
Sharpen drill
Hard spots in material

Large chip Coming Out Of One Flute Small Chip Out Of Other Flute-Solution
Check Drill point
Resharpen drill
Replace drill