From DXF drawing to sheet metal quote, with nesting

What is nesting?

Nesting is arranging the parts cut from one sheet as tightly as possible. The better the nesting, the fewer sheets an order needs and the less scrap is left. In sheet metal work, material is often the largest part of the price, so nesting drives the quote directly.

A simple method treats every part as a rectangle. Nesting software that works with the true shape rotates parts, fits them into each other's cut-outs and places small parts inside the holes of large ones.

In the demo, the sample order of ten part types fits on 2 sheets at 67.7 % utilisation. The same order as rectangles in columns reaches 55.6 %. If a usable strip of the last sheet is left over, the demo charges only the length used and the remnant goes back into stock.

How is the price of laser cutting calculated?

The price of laser cutting is laser time times the laser's hourly rate. The laser time follows from the nest: how many millimetres are cut, how often the laser pierces and how far the head travels between contours. Cutting speed and pierce time depend on material and thickness: 3 mm steel cuts much faster than 10 mm.

• Cut length divided by the cutting speed for that material and thickness.
• Number of pierces times the pierce time.
• Travel between contours divided by the rapid speed.
• A fixed time per sheet for loading and unloading.

How bending is priced

For bending, the demo uses a setup time per part type and a fixed time per bend, times the quantity. Ten brackets with two bends each cost one setup and twenty bends. Those minutes times the press brake's hourly rate is the bending cost.

A worked example

This is the quote the demo produces for the sample order in 3 mm S235 steel, on 3000 × 1500 mm sheets, without finishing. All rates are fictional; the point is the structure.

Every line shows its arithmetic, so a quote can be checked. The demo also splits the total per part into a price per piece, and gives an indication for two and five times the quantity.

Delivery date: when can it be ready?

A price without a delivery date is half a quote. The demo schedules the cutting and bending on the demo factory's existing schedule, adds the days for finishing and shows the expected delivery date next to the requested one.

With your own rates and machines

The demo uses fictional rates and one fictional factory. Trydent builds this kind of calculation as custom software: with your own material prices, cutting tables and hourly rates, your machines and your schedule, connected to the ERP or costing tool you already use.

Frequently asked questions

Can I use my own DXF drawing?

Yes. The DXF is read in your browser. Only the part contours are sent to Trydent's server, which nests them in memory and stores or logs nothing. Your file itself stays in your browser.

Is this nesting software I can buy?

No. Plaat tot offerte is a demo of what Trydent builds as custom software. The nesting works with the true shape of the parts, but the rates, materials and schedule are fictional.

Which materials and thicknesses can I choose?

S235 steel from 2 to 10 mm, 304 stainless steel from 1.5 to 6 mm and 5083 aluminium from 2 to 6 mm, on 3000 × 1500 or 2500 × 1250 mm sheets.