1D Nesting Optimizer for Bars, Tubes, Pipe and Extrusions

A 1D cutting optimizer answers two questions for straight stock: how many bars to buy, and which pieces come out of each bar. It needs four kinds of input, and every one of them changes the answer, so they sit in the left rail in the order a sawyer thinks about them.

Stock

Each length you can buy, with an optional quantity cap and price per bar. Material names keep T-slot out of window profile.

Kerf

The slot the blade removes, charged once per cut. On the 80/20 frame, 42 cuts at 3.2 mm eat 134.4 mm.

Trims

Squaring cuts at both bar ends. Mill ends are rarely square, so 10 mm per end is a common shop habit.

Goal

Lowest purchase cost, fewest bars or least stock length. With one price per metre they agree; with mixed prices they can differ.

The engine first tries an exact search over whole-bar patterns, which proves the plan cannot be beaten. Very large lists fall back to first-fit decreasing and the summary says Best found instead of Optimal. The bar and tube cutting optimization software guide walks through both methods on a real job.

Most cut lists already live in a spreadsheet. Select the rows in Excel or Google Sheets, copy, open Paste from Excel and press Replace cut list. The importer detects tabs, commas or semicolons and a header row, then reports exactly what it read, for example 3 rows (16 parts), before anything is nested.

A file works the same way: drop a CSV, TSV, TXT or job JSON of up to 5 MB on the import card. Headers such as Length, Cut length, Qty, Pcs or Mark are recognised; a file with no length column is refused with a message and your current list stays as it was. The 1D stock cutting optimizer for Excel guide has a copy-ready template.

With both ends at 45°, two pieces laid side by side leave a 60 mm triangle of scrap between them and need two saw cuts. Turn every second piece over and the ends become parallel: one cut makes both ends. That takes the window job from 6 bars and 40 cuts to 5 bars and 25 cuts.

Long-point lengths, along-axis kerf for 30°, 45° and 60° ends and when to leave the switch off are covered on the miter cut length optimizer page.

Every bar on the canvas carries its stop marks: the tape reading from the bar's left end to the right long point of each piece, kerf and trim included. Set the stop once per reading instead of adding piece lengths, so small errors never pile up along a 6 m bar.

Drops are graded as they are drawn. Anything at or above the reusable threshold is an emerald remnant you can rack and enter later as offcut inventory; anything shorter is hatched scrap. The frame job leaves 2 reusable drops, and the linear material yield calculator shows how the threshold changes the numbers.

ΔL = W · tan 45° = W  (saved per shared junction)
d = W · cot a  (end offset) · kerf along the bar = k / sin a

A 45° end on a profile 60 mm wide reaches 60 mm further along the fence face than along the far face. Lay two frame pieces side by side as cut and the gap between them is a 60 mm triangle of scrap plus two saw cuts. Turn every second piece over and the ends become parallel: one cut makes both ends, and the triangle disappears.

Only flip a profile that is the same on both faces: square tube, flat bar, symmetric flat strip. Thermally broken window sections, single-side painted bars and profiles with a glazing bead groove must keep their face up — leave the switch off for those jobs.