Ann, I just wanted to say. I know I go on and on about this 3D printing, but it just fascinates me to no end. We talked just a few months ago about materials and they are already here. Like you said, it's progressing very fast. I'm just really interested in this.
That person would still need machining knowledge. At least knowledge of the measuring tools. I can see it as a trade school thing. Now instead of going for machining you go for 3D printing. I might be wrong, but it seems possible.
I agree about tight tolerances. The fact that this technology is being used in commercial aircraft and medical applications speaks volumes about its success in achieving consistent, repeatable, very tight tolerances.
One more thought. One thing that comes to mind to me, being an ex-machinist is the precision i.e. tolerances they can hold. I am betting they get better at that. You can print something all day long with whatever material, but if you can't hold certain tolerances then it isn't good for precision work.
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