I would have to have a really good reason to need to print rock gear instead of buying from a trusted supplier. Life safety gear is one of those things that isn’t worth the risk to screw around with.
sure... but why not? stuff like Silent Partner are cool and super expensive because they aren't produced anymore. you may also agree with the fact that gear is sometimes expensive for what they really are. and i can see no problem in printing a carabiner that's proven to fail at the same rate of a commercial one, or custom nuts for a specific geography! and can't metal 3D printing be used at industry to lower the costs of production, given it's cheaper than more traditional methods?