Industrial 3D printing supplier ExOne's M-FLEX midsized metal printer is three times as fast and has a build volume more than seven times as large as the company's previous midsized machine. (Source: ExOne)
You are correct on the time required to build large parts. ExOne specs a minimum thickness of .1mm(.004") which could yield quite large build times, on the order of 2 hours per inch of thickness. Also, print precision is listed at .06mm(.0025") in the X/Y direction. In a lot of industries that would not be considered high precision so some post build machining might be required. All that being said, this is still exciting technology that is relevent now and will continue to improve in the future
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