What is Guillotine Cut?

A guillotine cut is a straight cut that goes from one edge of a sheet all the way to the opposite edge, dividing the sheet into exactly two rectangles. This is how panel saws and beam saws work: the blade travels the full width of the material in a single pass.

Guillotine vs. free cut. The alternative is a free cut (also called a non-guillotine cut), where cuts can start and stop anywhere on the sheet. CNC routers, laser cutters, and waterjet cutters can make free cuts. Standard panel saws and table saws cannot.

Why this matters for optimization. With a guillotine constraint, every cut must bisect the remaining piece edge to edge. This limits layout possibilities, which means more waste compared to free-cut layouts. The trade-off: any layout that satisfies the guillotine constraint can be executed on a standard panel saw without special equipment.

Free-cut advantages. Parts can be nested more tightly because the optimizer is not restricted to edge-to-edge cuts. Material utilization is typically 5-15% better. The trade-off: you need a CNC router or similar machine to execute the cuts.

Choosing the right mode. Most cutting optimization software lets you toggle between guillotine and free-cut modes. Choose guillotine if you are cutting on a table saw or panel saw. Choose free cut if you have a CNC router. SmartCutList supports guillotine-constrained layouts so your optimized diagrams work with any standard saw setup.

Industry note. The glass industry almost exclusively uses guillotine cuts because glass is scored and snapped along straight lines.