The crossover point: why 40-60k units a year belongs to one-shot forming

Every exterior program starts with the same spreadsheet: tooling CAPEX on one axis, per-part cost on the other, volume across the bottom. Steel wins that spreadsheet at high volume for one reason: it amortises enormous tooling across enormous runs. Change the volume assumption and the whole spreadsheet flips.

The cost structure of steel

A steel exterior program chains together multi-die stamping, welding fixtures, and a paint shop. The dies alone run into the billions of won; the paint line dwarfs them. That stack only makes sense when ~100,000 units a year spread the cost thin enough. Below that, unit cost climbs steeply and never comes back.

One set of moulds, one shot

One-shot forming collapses stamp-weld-paint into a single forming cell. Tooling CAPEX drops by roughly 70% versus the steel press line, and the part comes out of the mould finished, with colour, gloss, and structure included. The cost curve is nearly flat from the first ten thousand units.

Below steel’s break-even, the cheapest panel is the one that never needed a paint shop.

Where the lines cross

Plot the two curves and the crossover band sits at 40-60k units per year, precisely the volume envelope of PBVs, specialty EVs, tractors, and robot platforms. Above it, steel’s amortisation machine wins. Below it, one-shot forming is not a green premium; it is the cheaper option before counting a single carbon credit.

Add the rest of the ledger (40-50% less process energy, a recyclable part, a domestic material supply at ~40% lower cost than imports) and the band widens further. This is why we say NEXKIN was built for the PBV era rather than adapted to it.