Page 15 - Die_and_Molds_User_Guide_7861458_2017

1 90˚ Shoulder Milling

ISCAR endmills that are intended mostly for 90˚ (square) shoulder milling but used also for
milling slots and grooves, are being developed in the following directions:
• Endmills with indexable inserts of diameter range 8-50 mm
• Solid carbide endmills with diameters to 25 mm
• Replaceable milling heads with MULTI-MASTER adaptation (or simply MULTI-MASTER heads)
of 6-25 mm diameters
• Extended flute endmill cutters of diameter range 12-100 mm
The extended flute endmill cutters are for roughing, while the other kinds of
endmills are used in all kinds of operations: roughing, semi-finishing and finishing.

Insert with helical cutting edge
In the 1990’s ISCAR introduced new milling cutters which carried indexable sintered carbide
inserts APKT 1003 PDR-HM. It was the first insert with a helical cutting edge. Now an insert cutting
edge as a part of a helix that is built on a cutting cylinder seems apparent, and many tool
manufacturers use this approach for producing their milling inserts.
But in the 1990’s it was a real innovative solution. A helical edge ensured constant cutting geometry,
smooth cutting and considerably improved insert life. Ground HSS and solid carbide tools,
which were known long before, already had helical edges; however, the edge was made
by grinding. Nonetheless, producing a replaceable carbide insert with a helical edge by means of
pressing technology only was a serious problem at that time, and its solution by ISCAR brought
about revolutionary changes in the cutting tools industry.
HELIMILL – a line of new milling tools was born.

Endmills with Indexable Inserts Milling Tools
The main functional features of the most popular ISCAR endmills with indexable inserts are
summarized in Tables 3 and 4. Table 3 shows the number of teeth of the tools as a function of the
tool diameter and its maximal depth of cut; and Table 4 is intended for estimating the rampdown
ability of the tools.

Machining cavities is a typical feature of die and mold making. Hence, the ability to drill with
subsequent milling is an important attribute of a milling tool. Another significant factor is a tool
capability to ramp milling when the tool is simultaneously fed in radial and axial directions.
If the tool moves axially upward, it is ramp up milling (ramping up); and if it moves axially
down – ramp down milling. Maximal rampdown angle characterizing tool possibilities in ramping
is a valued feature for tool selection. The angle depends on cutting geometry and the nominal
diameter of a tool. For tools with high overhang from a toolholder (long and extra long series
of the tool overall length) the rampdown angle should be additionally diminished.
Three axes milling by helical interpolation is a widely used method for machining holes especially
with a large diameter. A cutter, which travels simultaneously along three coordinate axes of
a machine tool, moves planetary about an internal hole diameter and creates the summarized
cutting helical movement.
The helix angle is dependent of the maximal rampdown angle of the tool performed interpolation.
The helical tool path maintains smooth entry in the material and uniform loading of the tool.
The particular case of helical interpolation is two axes milling by circular interpolation when only
the planetary movement is made.
The depth of a machined hole depends on the maximal allowed depth of cut of the tool.
Chip evacuation and chip re-cutting are factors that affect a milling tool machined
cavities by a different technique.

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