The Arrival of Low-Cost Metal AM?
Systems just introduced promise to lower the price of entry for 3D printing metal parts.
You might be aware that I have been leading a double life. Along with my role for Modern Machine Shop, I serve in a similar role for a sister publication, Additive Manufacturing. The interest and activity around industrial 3D printing easily justified our launching a standalone publication on this topic several years ago. But even so, we need to cover additive in MMS as well, showcasing developments likely to directly impact machine shops. We might be seeing just such a development now. A recent advance in additive manufacturing technology promises to expand the accessibility and applicability of AM for metal parts specifically in CNC machine shops.
That advance was prominent at this year’s Rapid + TCT, a trade show focused on AM. At the show this year, various exhibitors showed new low-cost metal 3D printing systems—systems available for around $120,000. The price is notable not just because it is a fraction of the high-six-figure price that has come to be accepted for metal AM systems, but also because it matches what even a small CNC shop might spend for a piece of capital equipment.
Desktop Metal is a company offering one of these low-cost metal AM systems. The system builds metal parts via a process different from the powder-bed fusion and directed energy deposition processes established for metal 3D printing today. It prints metal by extruding polymer that carries metal powder, with the polymer later vaporized to leave a solid metal part. MarkForged offers a comparable AM system. And a newer and smaller company, Xact Metal, has a compact powder-bed fusion machine that hits the same price point.
There is a lot I still don’t know about these offerings. The further insight I hope to gain will come from users—namely, the kind of user who will take me aside to say, “The thing we have discovered about this type of machine is....” I am probably about a year away from getting that intel, if indeed there is anything like that to say. But for now, what these introductions seem to promise is nothing less than the chance for metal AM to become broadly more common in machine shops. And that’s huge.
Indeed, I have argued all along that 3D printing belongs in a machine shop, but this development changes the terms of my argument. Tooling and design prototypes ought to be made on a polymer 3D printer, I’ve said, so that CNC machines can make sellable parts. Adopting metal 3D printing for making end-use parts has been a step that some machining businesses have taken, but it wasn’t something shops everywhere could do. Now, lower-cost metal 3D printing might mean that shops will routinely employ both additive and subtractive methods for metal parts. And it might also mean that the range of metal parts suitable for additive is getting ready to expand.
Machining a large 3D-printed part for aerospace composite tooling is fundamentally different than manufacturing the part traditionally. Baker Industries knows this first-hand.
An engineering modification that would have been impractical or cost-prohibitive in the past is realized on a machine tool performing metal 3D printing and machining in the same cycle.
A hybrid system combining metal 3D printing with machining gives the Marine Corps perhaps its most effective resource yet for obtaining needed hardware in the field. It also offers an extreme version of the experience a machine shop might have in adding metal AM to its capabilities.