Cutting Guides
What Is Kerf and Why Does It Matter in Sheet Cutting?
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Kerf is the width removed by a cutting operation. Saw blades, router cutters and laser processes can produce different effective widths. Finished rectangles touching in a digital layout do not automatically leave space to cut both to size.
Start with the physical process
Enter a measured or process-appropriate clearance. Router cutter diameter is relevant to planning, but runout and machining strategy are outside the rectangular layout model. A saw kerf may differ from its blade body thickness.
CutNavi reserves entered kerf between parts. It does not compensate panel outlines into toolpaths, model cutter engagement or certify that a chosen spacing is sufficient for workholding.
A simple fit example
Two 600 mm-wide parts with 6 mm between them occupy 600 + 6 + 600 = 1206 mm. They cannot fit side by side in a 1200 mm-wide usable region. Entered spacing affects fit, not the finished 600 mm panel dimensions.
On a 1220 mm-wide sheet, a 10 mm margin at each side leaves 1200 mm. A layout that fits without margins can therefore fail after real boundary allowances are included.
Kerf is not sheet margin
Margin is an outer allowance; kerf separates parts. Do not add an allowance to each panel dimension and also enter it as margin unless that is intentionally your production rule.
The optimizer does not model common-line cutting. Neighbors are not assumed to share a zero-width cut, and placement labels do not prescribe a saw or router sequence.
Compare settings without inventing a process
In inch mode, bare 1/4 is exactly 6.35 mm. It differs from a 6 mm clearance. MM/IN switching lets you check representation without changing the physical setting.
Save alternatives as distinct runs and compare sheet count, utilization and unplaced parts. Smaller spacing can improve digital packing without being suitable for cutting. Use verified process parameters, not solely the percentage displayed by the optimizer.