
3D metal printing is about to go mainstream - phr4ts
http://newatlas.com/desktop-metal-3d-printing/50654/
======
Animats
There are many services printing metal parts. Shapeways has been doing it
since 2009. There are several workable processes. [1][2] This new machine
competes with the ExOne Innovent.[3] That uses a single-step process (no oven
needed) but is slower.

Desktop Metal's big claim is that they can lay down "up to" 8200 cm³/hr of
metal. The "up to" weasel words are a problem. They're vague about the layer
thickness. 3D printing has a basic trade-off between speed and precision. Most
of the commercial vendors go for high enough precision that you can make
working parts. Desktop Metal doesn't offer many pictures of their finished
parts, but I did find one.[4] That looks like it was made with layers of about
0.5mm. The furnace step provides some surface smoothing. That's not bad for
casting.

It's nice, but it's not clear that it's 100x, or even 10x, better than the
competition.

[1]
[https://www.youtube.com/watch?v=rEfdO4p4SFc](https://www.youtube.com/watch?v=rEfdO4p4SFc)
[2]
[https://www.youtube.com/watch?v=2vsaSzrhvcw](https://www.youtube.com/watch?v=2vsaSzrhvcw)
[3] [http://www.exone.com/Systems/Research-Education-
Printers/Inn...](http://www.exone.com/Systems/Research-Education-
Printers/Innovent) [4]
[https://embedwistia-a.akamaihd.net/deliveries/5c8aec78d82aa1...](https://embedwistia-a.akamaihd.net/deliveries/5c8aec78d82aa13cb56e05ccd8303e306ee711d2.jpg)

~~~
closeparen
It would be pretty exciting to duplicate keys (especially proprietary and "do
not duplicate" institutional keys) from the privacy of home. Might even hasten
the end of the mechanical lock as a security device.

Sure, you can do that now with Shapeways or a crooked locksmith, but it would
be fun to do independently.

~~~
schoen
It's certainly possible, but this kind of reminds me of discussions here on HN
and elsewhere about way that the 3D printing of guns can create a crisis for
gun control regimes. People in discussion threads reasonably pointed out that
it's been possible to manufacture guns in home workshops for hundreds of years
and that, for some kinds of weapons, it's not even toward the high end of
challenging metalworking projects, and that indeed many people regularly do it
either as a hobby or profession without 3D printing or even without CNC of any
kind.

But this is kind of shocking for software-oriented people who might think that
"manufacturing" "hardware" is a super-tough black art that can only be done by
professionals in factories. And indeed that's pretty much my intuition as a
software person who hasn't done woodworking since middle school shop class and
never learned any of the other manufacturing skills that humanity has been
working on for the last while. (Reading Bunnie's new book about manufacturing
in China has been fascinating for me, because it's like "oh yeah, so all of
these objects just come from people doing different tasks to fabricate them"!)

So people said about gun manufacturing that there was this funny intuition
that 3D printing somehow allows people to casually manufacture complex objects
at home which they otherwise simply couldn't do. But in fact, if people were
moderately motivated, they could easily learn some of the other techniques
that let them manufacture and/or duplicate objects. So we may tend to
exaggerate the impact by thinking that other methods represent a huge, hard
barrier while 3D printing represents true "push-button manufacturing". Neither
side of this intuition is necessarily the reality.

For the problem of duplicating proprietary keys, it seems like anyone could
already do this at home without especially expensive equipment and without
especially extensive training. I remember reading a Mickey Mouse cartoon from
many decades ago where a key was supposed to be duplicated from a negative
impression taken in some clay (or something), and this was presented as a
basic skill of a generalist mechanic!

On the other hand, maybe this intuition is partly right if some significant
population of would-be home gunsmiths or key-copiers _is_ intimidated enough
by hardware and manufacturing that they're sort of waiting around for the
pushbutton solution.

Edit: looks like other people in this thread have said this a lot more
concisely. :-)

~~~
jacquesm
> But in fact, if people were moderately motivated, they could easily learn
> some of the other techniques that let them manufacture and/or duplicate
> objects.

That's actually a substantial barrier. People are lazy, and pressing 'print'
on some design fed into a cornucopia machine (of which a 3D printer is a
rudimentary fore-runner) substantially lowers that barrier. It requires no
special knowledge beyond the feeding of raw materials into hoppers.

That's a lot less than what would be required to safely turn on a lathe, let
alone making something with it.

------
chroem-
It's like the brogrammer world just discovered powder metallurgy.

This exact technology has existed for decades but hasn't seen widespread use
because it has serious problems. I don't see any evidence that Desktop Metal
solved these issues either. The resulting parts have high shrinkage, poor
dimensional tolerance, and poor mechanical properties. The sintering process
leaves voids inside the material that serve as stress concentrations, causing
the material to fail well below its rated strength. Also sintered parts tend
to fail catastrophically rather than yielding since the adhesion between
particles is much weaker than the yield strength of the metal.

~~~
Tloewald
"brogrammer"

[https://www.desktopmetal.com/company/about/](https://www.desktopmetal.com/company/about/)

I see a bunch of PhDs with backgrounds in material science (among other
things). It's just possible they might have a clue.

~~~
chroem-
I'm referring to the hyperbolic headlines talking about a "metal printing
revolution," not the actual company. There are already off the shelf solutions
to do nearly the exact same thing that everyone here is getting all worked up
about. What's more, you could have purchased those solutions before the
internet was even a thing.

~~~
nharada
What does that have to do with brogrammers?

~~~
hapanin
I think OP is referring to the software-oriented HN crowd who have highly
upvoted this article despite little evidence that desktopmetal is doing
anything revolutionary.

------
ph0rque
$120k for the prototype printer, $360k for the production printer... still
about two orders of magnitude away from being practical for me to set up a
microfactory in my garage. Maybe by the time my car is self-driving and
earning me money instead of sitting in my garage, I can get that microfactory
set up affordably.

~~~
Nokinside
By the time you can afford that printer, there are others that cost $100k that
do better job. For most tinkerers it will be better investment to place order
in local metal workshop with has good printer than have your own cheap lathes,
CNC mills and 3d printers in the garage.

>Maybe by the time my car is self-driving and earning me money instead of
sitting in my garage, I can get that microfactory set up affordably.

Have you ever thought why there are no cheap capital assets sold in mass
markets for public that provide good ROI for no additional effort? (this is
good question for armchair economists)

~~~
noir_lord
> Have you ever thought why there are no cheap capital assets sold in mass
> markets for public that provide good ROI for no additional effort? (this is
> good question for armchair economists)

Pretty much for the reason you covered in paragraph one to be honest.

If I can achieve good with 10k and someone else can achieve awesome with 100k
then the person with 100k will win (assuming they can handle demand).

It's pretty obvious (if you look at..well every economic system ever really)
that capital begets capital.

It's not a huge thing, the US had this issue at the turn of the 20th century.

~~~
sliverstorm
Well, the other obvious reason is if everyone can achieve "good" for 1k,
everyone will make the investment, leverage the asset, and the ROI will
disappear because it was easy & accessible to everyone and becomes highly
competitive.

Bitcoin mining was a good example. Everyone has a graphics card, and mining
was pretty trivial. Great example of a cheap capital asset with low effort to
monetize. Quickly, the ROI slimmed until only large scale operations with low
costs and good economies of scale were profitable.

~~~
noir_lord
Yep but even there the people with the large amounts of capital won once GPU's
stopped been effective since they could afford ASIC's.

I think on some level society has always known this, having access to large
amounts of capital doesn't guarantee you'd win but if someone offered me the
choice between starting a game of monopoly with $100 or $100,000 I know which
I'd pick.

Fun trivia aside, Monopoly was created to demonstrate that activities that
promote wealth creation are more beneficial than ones that allow monopolists
to run amock.

------
50something
This is another Ric Fulop company, notoriously the founder of A123 Systems
[1]. That company also raised "a ton" of money but ultimately blew up, filing
for bankruptcy. I'm skeptical of this new endeavor because of both economics
and technology.

[1]
[https://en.wikipedia.org/wiki/A123_Systems](https://en.wikipedia.org/wiki/A123_Systems)

~~~
fudged71
Another huge concern is the fact that they are trying to push to market two
completely separate 3D printing process technologies, and are valued at over a
billion dollars before shipping a product. A few of their claims and marketing
materials are too hyped and there's a lot of skepticism about their actual
technology benefits. Limitless hype has been an ongoing problem in the 3D
printing field, and they seem to be capitalizing on it.

------
coredog64
> The company has raised a ton of money in the last few months...

> ...Desktop Metal's Studio machines are also a ton more practical to have in
> an office.

> But there's a ton of metal options...

I'm guilty of this too, but I think there are more ways to describe a plethora
of items than "a ton". Unless, of course, there are actually 2000lbs worth.

~~~
ClintEhrlich
Strictly speaking, a "plethora" should be an _excessive_ amount of something.

It still might work in this context though, if you think the company has
raised too much capital...

~~~
danudey
Well _technically_ , a plethora is a 'large _or_ excessive amount of
something', so I think in this case it works, though it feels a little
sesquipedalian.

[https://en.oxforddictionaries.com/definition/plethora](https://en.oxforddictionaries.com/definition/plethora)

~~~
ClintEhrlich
The entry you linked to agrees with my definition:

"Strictly, a plethora is not just an abundance of something, it is an
excessive amount."

------
sevensor
I don't think they make enough of this point:

> Depending on the nature of the part, it might be necessary to do some post-
> print surface finishing like sanding or bead blasting to smooth out the
> layered surfaces

If this is anything like the powder-bed parts I've handled, the layers are
going to be pretty rough. I wouldn't be surprised if they need some degree of
post-machining. Don't sell your CNC mill just yet.

Furthermore, 15% shrinkage during sintering? What's the dimensional tolerance
on the finished part then? I'm guessing it's not great.

~~~
pitaj
As long as the shrinkage is predicable, you could still have very good
tolerances

~~~
kevin_thibedeau
Somehow I doubt it. The shrinkage must be dependent on geometry/density and
their method of compensating can't possibly be good enough to hold tight
tolerance over an entire complex part.

~~~
WalterBright
Forgings and castings all shrink as well, because metal shrinks substantially
when it cools. The dies and molds are made oversized.

I corresponded with a guy who was making his own intake manifold for his
mopar. (A very cool project.) He made his own molds. I did some calculation,
and said he had to make the mold about 10% oversized. He told me I didn't know
what I was talking about, he couldn't believe it would shrink that much. His
cast manifold wound up 10% undersized :-)

Anyhow, dimensions that require tight tolerances get machined to spec after
the forging/casting.

~~~
NegativeK
> Forgings and castings all shrink as well, because metal shrinks
> substantially when it cools.

Forgings and castings also require post-op machining to bring them into tight
tolerances, which isn't something that fits the mental model of a lot of
people when it comes to 3d printers.

~~~
StillBored
People who don't own 3d printers. There is plenty of cleanup work on a 3d
print of any complexity. I find myself even drilling a fair number of holes in
some of my prints because the minimum consistent hole size my printer can
generate is a few mm.

------
1024core
What is the strength of such a part, compared to a regular cast part? Say I
3-D print a spanner. How well will it hold up against a spanner that was cast
and heat treated?

~~~
nnfy
The process in the article is effectively sintering. If [1] is any indication,
you can get to within an order of magnitude of strength of cast/forged parts,
if sintering variables are controlled for properly. Which may not be the case
for a diyer, metallurgy is a complex art.

1.[https://physics.stackexchange.com/questions/14635/what-
will-...](https://physics.stackexchange.com/questions/14635/what-will-the-
strength-of-a-sintered-steel-piece-be-compared-with-a-cast-piece)

~~~
__jal
Yeah and I also worry about shrinkage - they're saying ~15%, which would be a
massive issue with some profiles. I don't see how a lot of parts would work
very well without distortion.

------
simias
From the video:

 _The production system is cloud-connected_

Seriously, that's a selling point nowadays? I have to buy a hyper expensive
piece of hardware and if the company goes under I might not even be able to
use it anymore?

Not everything needs to be on a bloody cloud.

------
biggerfisch
> but the only affordable printing materials are cheap ABS plastics

Not very true at all. You can get PLA for $20/1kg or less. Even resin for SLA
printers is often possible to find for affordable prices, especially
considering that you can sometimes use less material without the need for
infill.

I'm really not even sold on the idea that so many people "need" metal
printers. Seems like most people would be way better off with the incredibly
cheaper plastic options.

~~~
aidenn0
Isn't PLA less structurally sound than ABS? I thought the reason it was used
over ABS was that it could be formed at a lower temperature.

~~~
thatsso1999
Yes, PLA is somewhat weaker, but still more than strong enough for most
desktop printing applications. It's also much less toxic to print with than
ABS.

~~~
takingflac
Can we get a citation for the toxicity of ABS? My Google-fu is failing me as I
can only find articles that say the fumes can cause minor irritation when
inhaled or in contact with the eyes.

~~~
thatsso1999
"The higher temperature ABS-based printers had total UFP emission rates nearly
an order of magnitude higher than the lower temperature PLA-based printers
(1.8-2.0 10^11/min compared to 1.9-2.0 10^10/min)."

"Primary gas-phase products of ABS thermal decomposition at very high
temperatures have been shown to include carbon monoxide and hydrogen cyanide,
as well as a variety of volatile organics (Rutkowski and Levin, 1986).
Exposure to thermal decomposition products from ABS has also been shown to
have toxic effects in both rats (Zitting and Savolainen, 1980) and mice
(Schaper et al., 1994)."

from [http://ac.els-
cdn.com/S1352231013005086/1-s2.0-S135223101300...](http://ac.els-
cdn.com/S1352231013005086/1-s2.0-S1352231013005086-main.pdf)

------
WhitneyLand
Any reason not to set default skepticism to high for Loz Blain and NewAtlas?

>...it's going to compete with traditional mass manufacturing

>...the hype is real

The team, tech, results, deals already signed, all seem really impressive in
their own right. No hyperbole needed to get a more views.

It's not my area, if someone tells me this really has a shot at competing with
mass manufacturing in the next 5 years I retract everything.

------
WalterBright
A forging is 3x the strength of a casting of the same part from the same
material. That's why when upgrading the power of your muscle car, forged parts
are the way to go.

What's the relative strength of 3D printing?

------
rrggrr
I'm told the metal powders are still more expensive than equivalent
traditional materials, and that in some cases (Ti) can be explosive. Anyone
know what the real economics are in terms of materials and energy costs?

~~~
bdamm
Aren't all metal powders explosive given sufficient dispersion in an oxidizer
and a source of ignition?

~~~
rectangletangle
Not all, but many. Particularly metals that would likely be used for printing
applications, e.g., iron and aluminum.

However a ton of materials are explosive if made into a fine powder then
dispersed, so this is more of a general fabrication issue, than something
unique to 3D printing.

------
QAPereo
Other than the temperature a relatively compact oven is potentially reaching,
what's the breakthrough here other than the successful funding?

~~~
ChuckMcM
Production time.

Production is always judged by how much time it takes for raw material to
become finished parts. Additionally that is split between 'operator time'
(person required) and 'machine time' (just the machine running).

'Operator time' is a function of how skilled the operator has to be
(machinists cost a lot more than technicians).

'Machine time' is a function of operating cost and depreciation.

So anything that shortens those times, or cuts those costs lowers the cost per
part. Parts "have" to cost less than a threshold amount to meet the sales
price of the final assembly + margin.

That is all basic manufacturing. The key is that costs have typically been
reached by doing things in volume with 'tooling' (investing in dies and jigs
to configure the machine to easily make the one part). That essentially makes
the production line 'single use' while it is tooled that way.

These guys are proposing that they can make metal parts at the same cost as
the tool and die folks in smaller quantity and with no setup costs. That
changes several things;

1) You can make warranty/repair parts "on demand" so cut the cost of making a
million widgets and storing them in a warehouse.

2) You can make 'small runs' of products for more specialized markets at a
price that the market will accept.

3) You can support more variations of a given product without your spare parts
inventory exploding.

4) Production can be parallelized from small scale shops so a large 'mega
factory' isn't needed, instead you can get a dozen shops with this gear to
work in parallel to meet your production target.

If they can pull it off, it really does change a lot. If they can get the
costs down further it opens the possibility of domestic delivery of parts from
a certified vendor rather than a warehouse somewhere.

~~~
zxcmx
In terms of second order effects, I think one interesting angle is that low-
setup manufacturing makes ip / copyright in the STL files more valuable.

If you don't have the design then a human needs to spend a bunch of time
dialling in the geometry.

I can imagine manufacturers wanting to find ways to "DRM" spare parts. One way
to do that might be to make it more costly to produce designs from first
principles. So having for example specific complex bits of geometry that
ultimately force you to license the authorised design if you want to
"economically" fab the part at low volume.

~~~
ChuckMcM
Absolutely. They are going to want to charge a 'tax' for a third party
manufacturer to make the part. Something that will be hard to enforce however.

------
kutkloon7
As a layman, I am skeptical. This is very similar to the promises that were
made regarding 3d printing of other materials, and those weren't quite
fulfilled.

Like many hyped new techniques, they end up as techniques that are almost good
enough to be practical.

------
plasticchris
4 furnaces per printer... reminds me of factorio

~~~
Dude2018
This is where I learnt the word from.

------
edanm
While (potentially) impressive, it's not clear to me that this will really
replace production. I mean, it's faster than other _printers_ , but still far
away from regular production speeds.

------
Dowwie
I've watched a few DIY foundry videos on YouTube where makers melt down
aluminum cans and scrap metal into chunks of metal, ready for re-use. I wonder
if these 3d printers will be able to use reclaimed metal created from a
similar type of process.

~~~
cr0sh
If you're already doing this, you probably have the skills and the tools to
make your own molds (3D printed in plastic even), mold a rough version, then
mill it down to proper tolerances. If your molds are good enough, and your
pour goes correctly, and your tolerance needs aren't that high - the part that
you get might only need a minimum of cleanup (sprue removal, some filing or
sanding, sand/bead blasting).

------
Glyptodon
Printing with improved PMC (which is what this sounds like) doesn't seem that
revolutionary to me... I know there was a Kickstarter a while back for metal-
based PMC-like filament to use in regular 3-D printers (for kiln firing
later), and I think somebody already makes a device to print using PMC itself.
While doing so precisely, strongly, and cleanly enough for mechanical
applications, and with a much broader spectrum of metals, is great, the prices
seem rather far from the headline hype. (Not that the current options I
mentioned don't leave much to be desired.)

~~~
fudged71
MiniMetalMaker was extruding a metal clay for sintering:
[https://www.minimetalmaker.com/](https://www.minimetalmaker.com/) mainly for
jewelry etc. There is also the Markforged Metal X
[https://markforged.com/metal-x/](https://markforged.com/metal-x/)

~~~
Glyptodon
Filamet is the Kickstarter'd filament I was thinking of. It looks like they've
got a decent product, though it also looks like the campaign became a bit
rocky (typical Kickstarter delays, etc.). (I didn't back, so can't speak to it
beyond appearances.)

------
nealrs
It's been about 10 years since I left Caterpillar --- but I don't think you
can weld (reliably) on PM / sintered parts. This was one of the concerns the
crotchety old manufacturing engineers brought up when I proposed replacing
some expensive machined bosses with a much cheaper PM part.

Then again, those guys really loved to say stuff like "no, that's not how it's
done." \- so maybe they're wrong / tech has improved significantly.

------
achow
> Each production printer can produce up to an incredible 500 cubic inches of
> complex parts per hour.

That is 124 iPhone 6 sized solid blocks per hour. Incredible indeed!

~~~
bdamm
Your sarcasm is noted and appreciated!

Of course, this isn't supposed to print easily stamped iPhone backs, it's
supposed to print fuel injectors, retention brackets, integrated linkages,
etc. Parts that are complex and costly to produce through traditional
machining but trivial to print.

------
steveklabnik
I don't know much about how Desktop Metal works; how does this compare to
things like ExOne?

------
zdmc
In case anyone else was wondering about the power requirement for the
sintering furnace: 208V 3-phase, 30A. The 3-phase requirement may be an
impediment to some hobbyists; they should probably offer it with a buying
option of their own branded inverter.

~~~
KaiserPro
The $300k + might be a bigger impediment.

a threephase supply is much cheaper.

------
smnplk
But could it print a CNC machine ?

~~~
dboreham
First it would print a locking mechanism to prevent the humans from unplugging
its power supply..

------
alvern
This may bring the per part costs closer to what prototyping costs come in at
for CNC machining or Metal Injection Molding.

I don't see this being used with a lot of exotic materials yet, but for
stainless steel this is great.

------
visarga
Doesn't oven treatment induce slight deformations?

~~~
bluGill
I think I can safely say that the parts won't be flat to 1000 of an inch
(.03mm) - or whatever your tolerance is. However this is something that any
existing process can achieve with arbitrary shapes either.

I think this process replaces sand casting, a process that also has many
slight deformations. You just make the parts a little big and then machine the
important sides to the exact side you need. The downside of sand casting is it
often leaves a little bit of sand embedded in the metal which will destroy
your tools. If the internal metal quality is as good as sand casting, the ease
of doing arbitrary shapes and lack of sand in the metal make it a winner. That
you have to have a lathe/milling machine to finish the part is not a change.

If the above is right (it seems reasonable, but I don't know if it is), then
beams and and flat stock will continue to be made with existing process.
However odd shaped things like an engine blocks it could be a winner.

~~~
tcpekin
Engine blocks will almost certainly remain as a cast part, simply due to the
production capacity of casting is orders of magnitude higher than additive
manufacturing, as well as being relatively cheap. Metal additive manufacturing
is currently used in aerospace to reduce complex assemblies of parts into a
single piece, or to make small complex shapes that can't be made by a
traditional machining or casting process. Additive manufacturing, for the
foreseeable future will not replace load bearing parts as well, mainly due to
the different processing steps load bearing parts undergo. It will also most
likely stay with aerospace for the time being, since the price per part is
prohibitive for automotive use currently.

[http://www.computerworld.com/article/3188899/3d-printing/boe...](http://www.computerworld.com/article/3188899/3d-printing/boeing-
turns-to-3d-printed-parts-to-save-millions-on-its-787-dreamliner.html)

[http://www.additivemanufacturing.media/articles/the-
aircraft...](http://www.additivemanufacturing.media/articles/the-aircraft-
imperative)

------
microcolonel
The idea of an "office-friendly sintering furnace" would have been comedy a
decade ago.

------
tintan
What advantage does metal printing offer over casting a 3d printed wax/resin?

------
sharemywin
How does this compare to a metal CNC machine? Cost and Speed?

~~~
lostapathy
CNC machines will probably continue to be the king of things they can machine.
The catch, though, is that you can 3d print a lot of structures you cannot
machine by any means (see: SpaceX SLS's their rocket nozzles).

You have to design for the manufacturing process. Parts designed for CNC
machining will always feel like a square peg in a round hole for 3d printing.
Once you start designing for 3d printing, though, things get more competitive
quickly. You can design parts to have hard to machine shapes, or parts that
would have too much waste to machine from a solid billet of material and 3d
print them without the waste.

Your computer case is bent up from sheet metal instead of machined from a
solid block of steel for a lot of obvious reasons, and it makes no sense to
compare the processes for a design like that. 3d printing will enable similar
shifts of design.

------
Iv
The game will radically change when metal printing arrives at the point where
it can print coils and make stators and rotors.

Wake me up when metal printing reaches that point.

------
bandrami
So, about those good manufacturing jobs...

------
pier25
So now anyone will be able to print a real gun with complete anonymity.

~~~
goodplay
As apposed to casting and cncing one yourself? People can already build guns
anonymously if they want (and many do).

People can also use current 3D printers to (mostly) print unconventional guns
anonymously. Do these printers also concern you?

Reaction to technology should be with reason, not fear mongering.

~~~
pier25
3D printing is much more convenient than casting. Also I assume metal printing
would make better weapons than plastic ones.

No fear mongering, just making an observation.

------
jkoll
Is this an ad?

------
pluio
Ok

------
nmyk
Guns for everyone!

------
HugoDaniel
\m/

