Formwork Plywood Cutting Optimizer

Method

How the plywood cutting optimizer works

Choose a stock sheet or enter usable dimensions after edge trimming. Add each finished panel size and quantity, then enter the saw’s cut width. If orientation matters, lock the panel so its length follows the stock sheet length.

The engine tries six deterministic layouts: three panel orderings paired with two cut directions. Each placement starts in a corner of a remaining rectangle. Straight cuts separate the panel and leave rectangular offcuts. This is a guillotine-cut heuristic: it chooses the result with fewer sheets and, on a tie, the largest individual offcut. It does not prove the minimum possible sheet count.

Every diagram uses X across sheet width and Y down sheet length. Panel IDs match your cut list. A rotation marker means length and width were swapped in that placement. Expand the ordered cut list to see where each straight cut crosses its current remaining rectangle.

Utilization, offcuts, and saw loss

1. Purchased area = sheets used × stock length × stock width
2. Placed panel area = sum of the finished panels actually placed
3. Material balance = placed panel area + rectangular offcut area + saw kerf loss
4. Utilization (%) = placed panel area ÷ purchased area × 100
5. Unused stock (%) = (offcuts + saw loss) ÷ purchased area × 100

Unused stock is not necessarily discarded waste. Some offcuts may suit another job; saw loss cannot be reused as a panel. If a blade extends beyond a narrow edge sliver, only material inside the sheet counts as saw loss. A panel that exactly matches a sheet dimension needs no separating cut on that edge.

Panels that cannot fit are listed explicitly. When any are unplaced, sheet and waste totals describe the partial layout only. When none fit, no sheets are allocated and percentage results are unavailable.

Worked example

Two panels with a 3 mm saw kerf

Use a stock sheet 1000 mm long × 1200 mm wide and two panels each 1000 mm long × 500 mm wide, with orientation locked. At 3 mm kerf, the first panel occupies X = 0–500 mm, the first saw band occupies 500–503 mm, and the second panel occupies 503–1003 mm.

The next cut uses 1003–1006 mm, leaving an offcut 1000 mm long × 194 mm wide. The 1.2 m² stock contains 1 m² of panels, 0.194 m² of offcut, and 0.006 m² of saw loss. Utilization is approximately 83.333%. With zero kerf, the offcut would instead be 200 mm wide.

From sheet estimate to a cutting layout

The Formwork Plywood Calculator estimates sheet demand from area and allowance. This optimizer checks the individual panel rectangles and cutting gaps. Equal total areas do not guarantee that the panels fit.

Use the Formwork Panel Waste Calculator to compare net panel area against a proposed purchase. A detailed cutting layout can explain why that purchase needs more sheets than an area-only estimate suggests.

Assumptions and limitations

• One stock sheet size and thickness, with unlimited sheets available. Existing offcut inventory and mixed stock sizes are excluded.
• Only rectangular pieces and straight-through cuts are supported. No arbitrary shapes, holes, bevels, or nesting around defects.
• Grain locks prevent 90° rotation; they do not check face grade, strength, or structural orientation requirements.
• Dimensions are rounded to the nearest 0.001 mm for consistent fit checks. Allow fabrication tolerance separately.
• Runs are limited to 30 panel types, 200 pieces, and dimensions up to 10 m to keep client-side work bounded.
• Suggested layouts require review for edge trim, blade setup, clamps, cut access, and safe handling.

Plywood cutting optimizer FAQ