Mechanics and dynamics of cutting with helical ball end mills are presented. The helical ball end mill attached to the spindle is modelled by orthogonal structural modes in the feed and normal directions at the tool tip. For a given cutter geometry, the cutting coefficients are transformed from an orthogonal cutting data base using an oblique cutting model. The three dimensional swept surface by the cutter is digitized using the true trochoidal kinematics of ball end milling process in time domain. The dynamically regenerated chip thickness, which consists of rigid body motion of the tooth and structural displacements, is evaluated at discrete time intervals by comparing the present and previous tooth marks left on the finish surface. The process is simulated in time domain by considering the instantaneous regenerative chip load, local cutting force coefficients, structural transfer functions and the geometry of ball end milling process. The proposed model predicts cutting forces, surface finish and chatter stability lobes, and is verified experimentally under both static and dynamic cutting conditions.

Issue Section:
Research Papers
Topics:
Dynamics (Mechanics), Milling, Cutting, Finishes, Geometry, Chatter, Databases, Kinematics, Stability, Stress, Transfer functions
1.
Altintas
Y.
, and
Budak
E.
,
1995
, “
Analytical Prediction of Stability Lobes in Milling
,”
CIRP Annals
, Vol.
44
, No.
1
, pp.
357
–
362
.
2.
Budak
E.
,
Altintas
Y.
, and
Armarego
E. J. A.
,
1996
, “
Prediction of Milling Force Coefficients from Orthogonal Cutting Data
,”
ASME JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING
, Vol.
118
, pp.
216
–
224
.
3.
Lim, E. M., Feng, H. Y., and Menq, C. H., 1993, “The Prediction of Dimensional Errors For Machining of Sculptured Surfaces using Ball-End Milling,” ASME Book PED, Vol. 64, pp. 149–156.
4.
Martelotti
M.
, “
Analysis of the Milling Process
,”
Transactions of the ASME
, Vol.
63
, p.
667
667
,
1941
.
5.
Martelotti
M.
, “
Analysis of the Milling Process, Part II—Down Milling
,”
Transactions of the ASME
, Vol.
67
, p.
233
233
,
1945
.
6.
Montgomery
D.
, and
Altintas
Y.
,
1991
, “
Mechanism of Cutting Force and Surface Generation in Dynamic Milling
,”
ASME JOURNAL OF ENGINEERING FOR INDUSTRY
, Vol.
113
, pp.
160
–
168
.
7.
Smith
S.
, and
Tlusty
J.
,
1993
, “
Efficient Simulation Programs for Chatter in Milling
,”
Annals of the CIRP
, Vol.
42
, No.
1
, pp.
463
–
466
.
8.
Tai
C. C.
, and
Fuh
K. H.
1994
, “
A Predictive Force Model in Ball-End Milling including Eccentricity Effects
,”
Int. J. Mach. Tools Manufact.
, Vol.
34
, No.
7
, pp.
959
–
979
.
9.
Tlusty
J.
,
1986
, “
Dynamics of High Speed Milling
,”
ASME JOURNAL OF ENGINEERING FOR INDUSTRY
, Vol.
108
, pp.
59
–
67
.
10.
Tlusty
J.
, and
Ismail
F.
,
1981
, “
Basic Nonlinearity in Machinig Chatter
,”
Annals of the CIRP
, Vol.
30
, pp.
21
–
25
.
11.
Yucesan
G.
, and
Altintas
Y.
,
1996
, “
Prediction of Ball End Milling Forces
,”
ASME JOURNAL OF ENGINEERING FOR INDUSTRY
, Vol.
118
, No.
1
, pp.
95
–
103
.
12.
Yang
M.
, and
Park
H.
,
1991
, “
The Prediction of Cutting Force in Ball End Milling
,”
Int. J. Mach. Tools Manufact.
, Vol.
31
, No.
1
, pp.
45
–
54
.
13.
Sim
C.
, and
Yang
M.
,
1993
, “
The Prediction of the Cutting Force in Ball End Milling with a Flexible Cutter
,”
Int. J. Mach. Tools Manufact.
, Vol.
31
, No.
2
, pp.
267
–
284
.
14.
Week
M.
,
Altintas
Y.
, and
Beer
C.
,
1994
, “
CAD Assisted Chatter Free NC Tool Path Generation in Milling
,”
International Journal of Machine Tool Design and Research
, Vol.
34
, No.
6
, pp.
879
–
891
.
This content is only available via PDF.
Copyright © 1998
 by The American Society of Mechanical Engineers
You do not currently have access to this content.