ORNL and Mazak Build a Hybrid Machining and 3D Printing System for Large Metal Parts

Additive and subtractive in one cell

The VC-Ez WAAM platform, co-developed by Oak Ridge National Laboratory and Japanese machine tool builder Mazak, is an attempt to solve a problem that has lingered in large-format metal 3D printing: deposited material rarely meets final tolerances straight off the print. Surface finish, dimensional accuracy and feature definition still need machining. The VC-Ez WAAM integrates both steps in a single automated cell, using directed energy deposition to build near-net-shape parts and five-axis milling to finish them to spec without removing the part from the machine.

How the two halves work

The additive side uses a WAAM system from Fronius, the Austrian welding specialist that entered additive manufacturing in 2024 with its CMT Additive Pro. The system deposits metal wire layer by layer using an electric arc, which is a fast and material-efficient way to produce large structural components. The Fronius welding head is mounted on the Mazak VC-Ez 20X machining center, which handles the subtractive work. That machine offers five-axis simultaneous machining with a traverse span of 800 by 510 by 510 mm and traverse rates up to 32,000 mm per minute across all three axes.

Once the WAAM deposition is complete, the system moves directly into machining mode. The Mazak machine's five-axis rotary-tilt trunnion table lets it reach features that would be inaccessible on a standard three-axis mill. Mazak's MAZATROL SmoothEz5 control handles programming for both the additive and subtractive operations, which simplifies setup for operators who may be more familiar with conventional machining than additive manufacturing workflows.

Automated pallet transfer between steps

The VC-Ez WAAM includes an automated palletized transfer system that moves pallets between the additive and subtractive stations. That automation reduces the amount of operator intervention required during a build cycle, which matters for production environments where the system is expected to run through multiple stages without constant supervision. The pallet transfer also means the same cell can handle multiple parts in sequence, each moving through deposition and machining without manual handling between steps.

Large-format parts with tight tolerances

The target for this system is large metal components where conventional manufacturing involves expensive tooling, long lead times, or both. Near-net-shape WAAM deposition gets the bulk geometry in place quickly using relatively low-cost welding wire. The subsequent machining pass removes only the material needed to achieve final dimensions and surface finish. That sequence can produce large structural parts at a lower cost and in less time than machining from solid billet, while achieving tighter tolerances than WAAM alone can deliver.

IMTS 2026 debut

The VC-Ez WAAM is making its public debut at IMTS 2026 in Chicago, where it will sit alongside other large-format metal additive systems. EOS is there with its six-laser M4 Onyx. Fronius is there with its new Additive Cell. The ORNL-Mazak platform occupies a slightly different position: it is explicitly hybrid, designed from the start to combine additive and subtractive in one workflow rather than treat them as separate steps. Whether that integration translates into faster time-to-part and lower cost per kilogram will be the question customers ask when the show is over.