1. 02/27/16 CNC Nesting & Programming1
CNC Nesting & Programming Guide
By Mal Moran
This presentation will demonstrate how using
various nesting techniques can help improve the
efficiencies of a CNC program.

2. 02/27/16 CNC Nesting & Programming2
A Nested Pair
If a part is shaped then a nested pair should be considered to
reduce waste between the parts. The CNC programmer of this
program has not produced a nested pair?
Note how the
increment has not
been reduced
leaving a gap of
32mm instead of
5mm?
Total waste =
27.9%

3. 02/27/16 CNC Nesting & Programming3
A Nested Pair
By producing a nested pair the waste of this program
has been reduced by 9.9%

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Comparison
Prog Length Width Height No.Prod Waste % Ord Qty M3
VX12811 2065 1926 992 496 27.9 464 3.69
Mal12 2068 1691 992 496 18 464 3.25
9.9 0.45 0.45
Waste reduction = 9.9%

5. 02/27/16 CNC Nesting & Programming5
A Nested Pair
This is a common way to create a nested pair. Depending on
the shape of a part the CNC programmer should always be
thinking of the most efficient nest / program.
Is this the most efficient nest for this part?
Nested waste = 27.5%

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NO!

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Stagger Nesting
Staggering or off setting a nested pair should always be
considered to reduce waste when creating a CNC program.
Complex shaped parts can require careful attention when
creating a program.
Nested waste = 12%

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Prog Length Width Height No.Prod Waste % Ord Qty M3
VX9953 1823 2196 1000 13944 32.5 574 0.16
Mal4 1936 2092 1000 16932 18.6 574 0.14
13.9 0.03 0.03
VX9953 Mal4
Comparison
Waste reduction = 13.9%

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Stagger Nesting Comparison
Prog Length Width Height No.Prod Waste % Ord Qty M3
VX13306 1591 1726 1000 160 21.3 466 8.00
Mal10 1252 1905 1000 160 9.4 466 6.95
11.9 1.05 1.05
Waste reduction = 11.9%

10. 02/27/16 CNC Nesting & Programming10
A Nested Pair Program
The CNC programmer of this program has created a nested pair
and has reduced the increment to the next nested pair.
Is this the most efficient nest?
V X 1 3 3 7 4

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NO!

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Rotate Nesting
Rotating a nested pair and reducing the waste between the
increment should also be considered when creating a CNC program.
The yield from a sheet / block could also improve.
M A L 1

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Comparison
V X 1 3 3 7 4
M A L 1
Prog Length Width Height No.Prod Waste% Ord Qty M3
VX13374 2272 1658 1000 30 48.3 99 12.43
Mal1 2100 1982 1000 40 39.7 99 10.30
8.6 2.13 2.13
Waste reduction = 8.6%

14. 02/27/16 CNC Nesting & Programming14
Summary
A nested pair can in most cases produce a more efficient
program.
Consider the scrap between parts and reduce the increment
where ever possible.
Staggering or rotating the parts could help to further
reduce scrap and improve the yield from a sheet or block.
Consider the block size / window when creating a CNC
program. Try to maximise a window of a block where ever
possible.