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Barrel Cutter




 Shapes a New                       When compared with a common taper endmill, the



                                    taper barrel provides theoretically pinpoint contact
 Milling Trend                      between the major cutting edge and a machined
                                    surface that decreases accuracy errors and prevents
                                    recutting of a produced shape. The taper shape also
                                    contributes to reducing tool overhang – an important
                                    factor for improving tool performance.
                                    Barrel and oval endmills are mainly utilized for cutting
                                    side surfaces. If machining a complex bottom surface
 Endmills featuring a cutting edge that is
 actually the segment of a large-diameter arc   is needed, a lens-shape endmill offers a good
 were introduced approximately 25 years ago.   solution. This tool features barrel cutting edges on its
 As the cutting-edge shape of these endmills   end surface to ensure milling with a large stepover.
 is reminiscent of a barrel profile, terms such
 as "barrel milling cutters", "barrel endmills"
 or, in shop talk, often simply "barrels" soon
 became common when referring to these
 types of endmill.




 At first, the use of these barrel-shape mills was
 limited more or less to a few specific applications,
 such as machining 3D surfaces of complex dies and
 turbomachinery components. However, advances
 in 5-axis machining and in CAM systems have
 significantly expanded the boundaries of barrel
 endmill applications.
 Traditionally, ball-nose and toroidal cutters
 perform these machining operations. However,
 the large-diameter arc of the endmill cutting
 edge results in a substantial reduction of
 the cusp height generated between passes   The barrel endmills - classical barrel-, oval- and lens-
 machined by a ball-nose or toroidal cutter.    shaped cutters - provide efficient tools for machining
 Another advantage of this type of cutting   3D surfaces. Nevertheless, for a long time the
 edge versus ball-nose and toroidal   complexity of CNC programming for applying barrel
 cutters is a significant increase in the   endmills was a constraining factor in actively integrating
 distance between passes (a stepover   these promising tools into the appropriate branches
 or a stepdown,  depending on the   of the metalworking industry. The growing use of
 direction of a cutter displacement   5-axis machine tools and the latest progress in CAM
 after every pass) - at least five times   and, subsequently, machining time can be   software has changed the situation dramatically, and
 more without degradation of the   noticeably reduced. Increasing the distance   today we see intensive utilization of barrel endmills in
 surface finish parameters! This   between passes also improves tool life and,   manufacturing various parts with geometrically complex
 means that the number of passes   therefore, diminishes tool cost per part.  surfaces. The main consumers of these "cutting
                                    barrels" are producers of aerospace, die and mold,
                                    medicine, turbine and compressor components.



 TELLIGENTLY
 12  MACHINING  IN  DUSTRY 4.0                                                                           ISCAR    13
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