Before the first weld: what tube laser cutting does for a steel furniture frame

A steel frame for a school chair or desk starts well before welding. It starts when a bar of steel tube is cut to length, pierced and shaped at the ends. When all of that happens on a fibre tube laser while the tube is clamped once, the parts reach the welding robot fitting together the way the drawing says. That fit is what lets a weld repeat across thousands of frames.

Back in July, when we wrote about robotic welding, we promised to come back to the step before it. Here it is.

How is steel tube for furniture frames usually cut?

The traditional route will be familiar to anyone who has stood in a metal shop. A saw cuts the tube to length. The piece then moves to a drill or a press for holes, and if the end has to be shaped, it goes to a notching press as a separate job. Every move means a new clamp and a new reference point, and with them a tiny new error. Each one on its own is small. Over three or four operations they add up to the difference between a joint that closes and a joint with a gap.

On a fibre tube laser the length, the holes, the slots and the shaped ends are all cut in one setup. The tube turns in the chuck while the cutting head follows the program, and a finished part drops off the end.

Why does cutting precision matter for robotic welding?

A welder with a torch sees a gap and adjusts: moves a little slower, adds a little more wire. A robot follows the path it was taught. Its sensors can correct a small shift in where the seam sits, but they work best when parts barely vary, and the more one tube differs from the next, the more one seam differs from the next.

The clearest example is the spot where one round tube meets the side of another. Left square from the saw, the end touches its neighbour at two points, and the weld has to fill everything in between. The laser cuts that end as a saddle that follows the curve of the other tube, so the two meet along the whole edge and the weld only has to join them. On frame 3,000 that joint looks the way it did on frame 30.

That is why laser cutting and robotic welding run as one process in two steps. The Panasonic TAWERS and Yaskawa cells from the welding issue do their best work when every part they receive is already where the program expects it.

Why does scrap matter more this year?

There is a second reason this step deserves attention now. Steel in Europe has become noticeably more expensive since January, as carbon border costs and tighter import quotas worked their way down the supply chain, and anyone who buys steel or steel products has seen it in their quotes. Once the raw material costs more, the share of each bar that ends up as scrap stops being a workshop detail.

Before the first cut, the software lays parts out along the bar much as a tailor arranges a pattern on fabric, mixing long and short parts so the offcut at the end stays as short as possible.

What can a laser not fix?

A laser cuts exactly what the drawing says. Wall thickness and steel grade are set by the specification and the mill before the tube ever reaches the machine. A precise cut also only pays off if every step after it keeps that precision, from the welding jig onwards.

What can a buyer check on a sample?

You don't need a workshop for this. Next time samples arrive, turn a chair over and look at the places where one tube meets another. Run a finger along the seam and feel whether it is even from end to end. Then turn over a second chair from the same delivery and find the same joint. If the two look and feel alike, the parts behind them were made alike, and that is what you want from the hundredth chair in a classroom as much as from the first.

If you'd like to see a sample or our 2026 catalogue, use the button below.

GEROM supplies school, kindergarten and office furniture to distributors and buyers across Europe, with a 30-day production cycle for serial orders.