The Cut List

A Tenon design is not a drawing of one object. It is a cut list: shared stock, plus a list of line items to cut from it.

design
├── stock          one board, one material, one cutter — shared by everything
└── items
    ├── project box   L=310 W=210 H=110   × 3
    ├── divider       3 × 2 spots         × 1
    └── marker        "whatsit.ca"        × 2

Why stock is shared

Because you cut a job, not a part. Every item on the list goes onto the same sheet in the same setup, so the board, the material and the cutter belong to the design rather than to any one item.

It also keeps the joinery honest. Finger joints are cut from the material thickness — a 6 mm box and a 9 mm box are different geometry, not the same geometry scaled. With one shared thickness, every item in the design agrees about the material it is made of, and changing it updates all of them at once.

Why items carry quantity

Quantity belongs to the item because the nester needs to place every copy. Three boxes is not one box cut three times: it is fifteen pieces that all have to fit on the board together, and the layout is different from one box's.

The status line under the preview reads out both numbers — parts (distinct shapes) and pieces (how many get cut).

Editing is live

Every change — a parameter, a quantity, an item added or removed — recomputes the parts and re-nests the sheet immediately. There is no generate step and no stale preview: what you are looking at is the job.

The design is the file

A design saves as a .tenon file containing exactly this structure: the stock block, then the items with their parameters and quantities. Nothing is baked; opening it rebuilds the parts from the parameters, so a design saved against 6 mm ply can be re-cut in 9 mm by changing one number.