The Moon undoubtedly has plenty of metallic ore ready to be mined by either robots or explorers. However, making metal from that ore is expensive in energy and time, both of which are limited in any early lunar exploration scenario. So it would probably be better to use the much more straightforward process of recycling existing metal. At least, that is the thinking underpinning the research done at Incus. The company uses a technique known as Lithography-based Metal Manufacturing (LMM), which combines a metallic powder with a binding agent and then cures the resulting blend using ultraviolet light. Afterward, it is sintered together to make a completed part without all the waste of traditional “subtractive” manufacturing processes.
But on the Moon, that process has an added challenge. As with all other competing processes, it has to deal with that most annoying of lunar substances – dust. Lunar dust is notorious for the problems it causes, and those problems extend to becoming ingrained in manufacturing processes like LMM. With too high of a dust concentration, the curing and binding don’t work, and the metal parts that are being printed literally crumble back to dust.
This is particularly acute for recycling projects that would utilize metal from things like rovers and solar panels that would have been exposed to lunar dust for a significant amount of time. It would be impractical to clean them thoroughly before recycling them, mainly because of how notoriously sticky lunar dust can be. So, for processes like LMM, which ideally use powder from recycled parts on the Moon, there is a high likelihood of a significant fraction of lunar dust, rather than just metal, in that powder feedstock.