On 23 Oct 2015 15:51:28 -0300, Mike Spencer
wrote:


Ed Huntress writes:

On Fri, 23 Oct 2015 07:42:33 -0700 (PDT), "
wrote:

Actually I am interested in hearing from those doing it, but also
those that have decided it is not worthwhile, and even from those
that are studying it.

Early on when this stuff was being invented and the printer was a
hacked dot matrix machine under a mare's nest of tubes and cables,
late 80s maybe, I saw an experimental setup at MIT. They were printing
with glue and steel spherules. After sintering, the result was put in
a puddle of another metal (bronze? brass?) in an oven. The molten
metal was drawn into the interstices by osmosis. I don't think it was
a very successful technique but I haven't kept up on the subject.

I have little to offer here. My focus is on the big commercial
printers, mainly laser-sintering machines for metal.

I've heard that complex pattern-welded billets are being made by 3D
printing differeing steel grains, sintering, then fusing at a welding
heat and/or under a press. Didn't get the details.

Oh, man, that should be great for making machined-billet brake pedal
arms and such, for people you wish wouldn't show up for work in the
morning!

Speaking of exotic metals, here's one from Boeing that they describe
as he "Lightest. Metal. Ever." It will be appreciated by some in this
group because it's 99% air:

https://www.youtube.com/watch?v=k6N_4jGJADY

--
Ed Huntress