Nesting software for laser cutting

The machine changes the numbers you nest with more than it changes the workflow. A fiber laser cutting sheet steel removes roughly 0.004 to 0.012 in (0.1 to 0.3 mm) of material, so parts can sit close together and the sheet fills tightly. That is true whether the machine is a Bodor, a Boss Laser or an OMTech fiber in a small shop, or a Trumpf or Bystronic on a production floor: the number comes off your own test cuts, not off the badge. A CO₂ laser on acrylic, plywood or MDF cuts wider, often 0.008 to 0.02 in (0.2 to 0.5 mm) and more as the material thickens, with a tapered rather than square cut face. A diode machine is wider again and slower, so the gap between parts usually gets set by scorching rather than by the beam itself.

Heat sets the floor on part spacing. Thin stainless and aluminium move as they cool, and two cut edges a few thousandths of an inch apart share that heat, so the web between them can bow or a part can tip into the cut. The right minimum spacing is the smallest gap your material tolerates without distortion, not the smallest gap the geometry allows. Part spacing in nesting works through what that setting costs in material.

Lapas places parts by part spacing, so set part spacing to cover your kerf. Kerf is the width the beam removes, taken from your own test cuts rather than a spec sheet; add the clearance you hold on top of it and the layout stays true to the parts that come off the table. See what kerf is if you have never had to measure one.

Sheet size is set per job, in inches or millimetres, so you enter the plate the way the rack is labelled: 48 x 96 in (1,219 x 2,438 mm) for a standard 4 x 8 ft sheet, 60 x 120 in (1,524 x 3,048 mm) for a 5 x 10, or whatever the drop measures. Inch values go in as decimals.

Lapas nests. It does not replace the CAM step that assigns cut order, power, speed and gas, and it is not trying to. The finished layout exports as a DXF that opens in the software you already run: LightBurn, RDWorks, Cypcut, LaserCAD, Fusion 360, SheetCAM, or anything else that reads DXF. That is the whole relationship: Lapas writes the DXF those tools read, and there is no plugin, no add-in and nothing about the machine that has to change.

G-code export is available on both plans for simple 2-axis work, but the output has not been validated across controllers and machines, so DXF into your existing CAM stays the production path and anything posted as G-code should be checked before it runs. Once the layout is in CAM, cut sequence is where the remaining time on the job is won.

Two things about a laser layout matter more than the last percent of density. Common-line cutting places two parts so they share one cut path, which removes a pierce and a kerf width from every shared edge and pays best on straight-sided parts in quantity. Micro-joints hold finished parts in the skeleton so they cannot tip into the beam or drop through the slat bed, which is what usually goes wrong when small parts are nested tightly on thin sheet.

Both are decisions about the cut program, and both are easier to apply when the layout is predictable: parts aligned, rotation locked where the material has a grain or a brushed direction, and spacing consistent across the sheet.

The engine is measured rather than described. Lapas Core v1.1 was run against deepnest-next v1.5.6 over 37 nesting cases and scored by an independent program that recomputes every number from the output geometry. On the 10 ESICUP academic instances Lapas Core averages 86.1% packing density against 73.3%, so 13.9% of the sheet is offcut versus 26.7%. Across 10 sheet-metal jobs it uses 25 sheets against 28, and it reaches a tighter nest in 10 seconds than Deepnest reaches in 5 minutes. On 7 of those 10 real jobs the two tie on sheet count, which is worth knowing before you switch anything. The full run, including the cases Lapas does not win, is on the benchmark page.

Against hand nesting the framing is looser and stays that way: most shops see 15-30% better utilization vs. manual nesting, and typical results vary by job type and current method.

Nesting and re-nesting are unlimited on the free plan, with no cap on parts per job and the full engine rather than a cut-down version. Upload a real production file, run it, drag or rotate any part the automatic layout placed badly, and run it again as often as you like. The free plan includes 5 project exports a month in any format, DXF, SVG, G-code and the PDF report among them, and re-exporting a project you have already exported is free for 7 days. No credit card is required to start. Pricing has the Pro plan, which removes the export cap and adds full project history.