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HEIDENHAIN TNC 407 (280 580) User Manual User Manual

Page 223

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8-16

8

Cycles

TNC 407/TNC 415 B/TNC 425

8.2

Simple Fixed Cycles

A

B

C

DR+

DR–

F

R

CIRCULAR POCKET MILLING (Cycle 5)

Process

• Circular pocket milling is a roughing cycle, in which the tool penetrates

the workpiece from the starting position (pocket center).

• The cutter subsequently follows a spiral path (shown in Fig. 8.10) at the

programmed feed rate. The stepover factor is determined by the value
k (see Cycle 4, RECTANGULAR POCKET MILLING: Calculations).

• The process is repeated until the programmed milling depth is reached.
• At the end of the cycle, the tool is retracted to the starting position.

Required tool

The cycle requires a center-cut end mill (ISO 1641), or pilot drilling at the
pocket center.

Input data

• SETUP CLEARANCE

A

• MILLING DEPTH

B

: pocket depth.

The algebraic sign determines the working direction (a negative value
means negative working direction).

• PECKING DEPTH

C

• FEED RATE FOR PECKING:

Traversing speed of the tool during penetration

• CIRCLE RADIUS

R

:

Radius of the circular pocket

• FEED RATE F:

Traversing speed of the tool in the machining plane

• DIRECTION OF THE MILLING PATH:

DR + :

climb milling with M3

DR – :

up-cut milling with M3

Fig. 8.11:

Cutter path for roughing-out

Fig. 8.12:

Distances and infeeds for
CIRCULAR POCKET MILLING

Fig. 8.13:

Direction of the cutter path

Starting Point

At cycle call with radius compensation R0, the tool must be positioned:

• at setup clearance over the workpiece surface in the tool axis
• at the center of the pocket in the working plane