Page 57 - Die_and_Molds_User_Guide_7861458_2017

Table 39 MILLSHRED General-purpose Serrated Round Inserts RCMT…FW.
Basic Feeds, mm/tooth
Basic starting feed fzo, mm/tooth, for inserts
ap/r Ø12 Ø16 Ø20

ap fzo ap fzo ap fzo
ap min 0.9 0.3 1.2 0.4 1.2 0.52
1/4 1.5 0.28 2 0.35 2.5 0.46
3/10 1.8 0.25 2.4 0.32 3 0.42
1/2 3 0.22 4 0.28 5 0.35
5/8 3.75 0.15 5 0.2 6.25 0.25
3/4 4.5 0.15 6 0.2 7.5 0.25
7/8 5.25 0.15 7 0.2 8.75 0.25
1 6 0.15 8 0.2 10 0.25
The feeds relate to workpiece material groups 1-9 (plain carbon and low alloy steels).
For machining groups 10-11 (high alloy and tool steels) the table values should be
multiplied by 0.9, for machining groups 15-18 (cast iron) – by 1.3 and for machining
group 38.1 (hardened steel, HRC 45 max) – by 0.6.
- Recommended depths of cut

Table 40 MILLSHRED Serrated Round Inserts RCMT…FW-T20.
First choice for machining martensitic stainless steel can also be used for
machining carbon and low alloy steels
Basic starting feed fzo, mm/tooth, for inserts
ap/r Ø12 Ø16 Ø20

ap fzo ap fzo ap fzo Milling Tools
ap min 0.9 0.26 1.2 0.35 1.2 0.4
1/4 1.5 0.23 2 0.3 2.5 0.35
3/10 1.8 0.21 2.4 0.28 3 0.3
1/2 3 0.18 4 0.25 5 0.28
5/8 3.75 0.13 5 0.18 6.25 0.21
3/4 4.5 0.13 6 0.18 7.5 0.21
7/8 5.25 0.13 7 0.18 8.75 0.21
1 6 0.13 8 0.18 10 0.21
The feeds relate to workpiece material groups 12-13 (ferritic and martensitic stainless steels).
For machining groups 1-9 (carbon and low alloy steels) the table values should be multiplied by 1.1.
- Recommended depths of cut

Example
A mold part from AISI 420 stainless steel with a thin-walled complicated shape and non-uniform
machining allowance is milled by tool ERW D020A032-B-3-C32-12 carrying inserts RCMT 1206-
FW-T20 IC928. Due to the unsteady allowance the depth of cut varies from 3 to 4 mm. The tool
performs cutting with 220 mm overhang from a collet. Find feed per tooth needed for programming
the tool path.

The material represents group No.14; ratio “overhang/diameter” is 220/32=6.9. Although Table 40
does not contain the basic feed for 12 mm diameter inserts with 4 mm depth of cut (worst case of
loading) directly, it is easily seen that it is 0.13 mm.
Consequently, the starting programmed feed is: 0.13×0.7=0.09 (mm/tooth).

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