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Cutting Formula of i-Center

● Attention of Form A+B insert:
  Reduce 30% of Spindle speed and keep same feed rate (mm/rev.) while depth L2 is reached.
● Using your “d1” value and cutting speed Vc from the data sheet, calculate spindle speed “S”(r.p.m).
● “ F” feed rate per minute F = S x f = IPR x r.p.m.

Metric Formula
d1 Center diameter mm  
Vc Cutting Speed m/min.  
S Spindle speed r.p.m (Vc x 1000)/(π x d1)
f - mm/rev.  
F - mm/min. Sxf
Inch Formula
d1 Center diameter inch  
S Spindle speed r.p.m  (3.82 x SFM)/(d1)
SFM Surface speed ft./min. Vc (m/min.) x 3.28
f IPR inch/rev.  
F - inch/min. IPR x r.p.m.

Technical Guide of Nine9 center drill

Cutting Data

dia.1to 3.15mm center drill bit cutting data
dia.4 to 10mm center drill bit cutting data
>> Cutting Data PDF File Download About Indexable Center Drill.

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