Drilling, 1 8 mac h ining inf o rm ation – HEIDENHAIN CNC Pilot 4290 V7.1 User Manual
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6.1
8
Mac
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ining Inf
o
rm
ation
Roughing limit behind cutting limit
Example 2: The roughing limit (SU) is located behind the cutting limit,
inside (SBI).
Abbreviations
SBI: Cutting limit, inside
SU: Roughing limitation (SU = sbl + ULI)
sbl: Basic length of roughing cut (“deepest” point of inside contour)
ULI: Overhang length, inside (machining parameter 4)
nbl: Usable tool length (tool parameter)
Drilling
TURN PLUS distinguishes the following drilling operations:
Drilling without fit specifications: The AWG selects tools that
permit machining to finished dimensions. First it searches for twist
drills, then for boring bars with indexable inserts.
Drilling with fit specifications: The AWG drills the hole in two
steps:
Drilling with smaller diameter than the nominal diameter of the
hole.
“Reaming” to finished dimension
TURN PLUS only evaluates the information “with/without
fit.” The type of fit (H6, H7, ..) has no effect.