| Cause |
Failure condition |
Countermeasure |
D
r
i
l
l
B
i
t
D
e
s
i
g
n |
Small margin width |
Promotes diameter wearing |
Enlarging margin width. Set suitable margin length. |
| Unsuitable tungsten carbide material |
Excessive wearing reduces drill diameter |
Use wear-resistant WC material. |
M
a
n
u
f
a
c
t
u
r
e |
Corrosion of tungsten carbide material |
If used drills are soaked excessively in acid
or water, its causes a CO deficit, which weakens the characteristic
of the Tungsten Carbide and can cause premature wearing |
Avoid keeping drill bits in high humidity places
and soaking in acid/waterfor a long time. Dry cleaning is recommended
process for cleaning. |
D
r
i
l
l
i
n
g
C
o
n
d
i
t
i
o
n |
To many hit counts |
To many hits promotes wearing |
Set suitable hit counts. |
| Low chipload |
Wearing increases because of long contact time
of drill bit with PWB. |
Apply suitable chipload. (Please refer to drilling
parameters.) |
| High spindle speed |
Wearing increases because of long contact time
of drill bit with PWB. |
Apply suitable spindle speed. (Please refer to
drilling parameters.) |
| Excessive number of repoints |
Accumulation of diameter wearing causes large
wearing. |
Reconsidering the number of repoint times. |
P
W
B
S
e
t
t
i
n
g |
Hinge number and thickness of PWB copper layers |
Increased tool load, promotes wearing |
Decrease PWB stack heights and hit count to reduce
drill bit damage. |
| Hard cutting PWB material |
Increasing tool load, resulting in wearing and
breakage. |
