
174 Fundamentals of Machining Processes
cosφ
c
=−1
t
The time of contact between the workpiece material and the cutting tooth, t
ϕ
,
becomes
φ
=
×
c
t
φ
=
−
−
cos( )
1
12
/
The maximum chip thickness, h
e
, can be calculated. Because
sin φ
c
e
=
hS
ez c
c
==si
in
It follows that
sin φ
c
=−−
11
2
2
t
d
or
sin φ
c
= 2
t
Therefore, h
e
becomes
h
f
t
e
=
2
6.3.1.4 Forces and Power in Milling
The maximum tangential force on a single tooth, F
e
, is
eswe
Fkb
f
t
esw
N/tooth=
2
The mean tangential cutting force, F
m
, becomes
mswm
where h
m
is mean chip thickness
Fkb
f
t
msw
N/tooth=