CutOptim’s 2D Panel optimizer normally plans for a panel saw: every cut runs from one edge of the remaining sheet to the other. A CNC router does not need that. CNC mode places the parts freely on the sheet — like a nesting program — so more parts often fit on the sheets you have.

When to use it

Use CNC mode when you cut the parts with a router, laser or waterjet from rectangular sheets. Keep it off for a panel saw, table saw or track saw: a free layout usually cannot be cut edge to edge.

How to switch it on

Open Settings (top of the left sidebar in 2D mode).
Tick CNC mode (free placement). Your choice is saved with the project.
Run the optimization as usual.

Settings that matter on a CNC

Blade kerf is the gap between two parts: your bit diameter + the free space you want between parts (for example a 6 mm bit + 3 mm = 9 mm). The CNC / router: tool + allowance link under it lets you type the two separately. The link appears once CNC mode (free placement) is ticked.
Trim per side (Settings → More) is the margin you keep free at the sheet edges; 0 lets parts touch the edge.
Limited in the stock box: switch it on to use exactly the sheets you have (quantities are hard limits — good for offcut strips).
Grain direction: a part with a grain direction (decor, veneer) is never turned against the grain; set it with the grain icon on the part row and on the sheet row.

What changes in the result

The parts are placed freely; the cutting sequence and the saw plan are not shown (there are no saw cuts).
Cut length is the total outline length of the parts — the router’s path.
Labels, the PDF, Excel, SVG and DXF work as before. DXF (CNC) puts every sheet into one drawing with the part names; your CAM software (for example Aspire) adds the toolpaths. The DXF WASTE line can use the bit diameter (the Tool diameter field under the WASTE checkbox), and the part labels in the DXF are sized to the part.

In CNC mode: grain matching (sets) works too — each set is placed as one block, freely like any other part. The saw-only settings (first cut direction, max cutting stages, minimise rotation, cut order, speed vs density, cost per cut) are dimmed and have no effect. Which sheet? compares free layouts too and is marked CNC mode. A CNC plan is made for a router — do not cut it on a panel saw.

Search harder: with Sheet supply set to Limited, the Search harder (up to 30 s) button in the Not enough stock block searches free layouts in CNC mode, and saw-cuttable layouts otherwise (details in Limited stock and priority cuts).

With Unlimited supply and two or more sheet sizes, Search harder for less material (usually under 15 s, at most 30 s) looks for a mix of sizes that uses less material (details in 2D Panel Cutting).