[Arm-netbook] Existential 3D Printing Moments

[Neil Jansen]

On Thu, May 18, 2017 at 12:31 PM, Luke Kenneth Casson Leighton <
lkcl at lkcl.net> wrote:
>
>  awesome, i'll email you privately.  letting people know what's
> happening is an important part of this project so a summary afterwards
> would be great.  i know the RSI thing well...

Notes / minutes from today's voice call are below.

lkcl recently had concerns on the CrowdSupply campaign update page, on how
to effectively scale up manufacturing a large amount of parts using a small
farm of 3D printers.  His concerns were over which type of 3D printer to
use, whether to "redesign" a printer vs. just buying them.  Which types of
filament to trust vs what can't be trusted.  Also over where the
Western-based 3D printing open source ecosystem is and where it's heading
compared to the Asian companies that have popped up.  I've ran a 3D printer
farm and printed over 100kg of filament for weeks and weeks on end, while
trying to fulfill our orders.  Our project was a 3D printable SMT pick and
place machine that was completely open source.  After that I went to China
to try and get it designed for manufacturing, so this is an area that I've
got some experience in.  I'm not really trying to step on any toes, this is
all FYI, hopefully it's useful to you.


* I recommended the Lulzbot Taz as a great example of a modern open source
hardware company that makes an excellent product that is up to the job of
manufacturing at the scale that your require.  Aleph Objects literally does
this, a significant chunk of their machines are 3D printed on their own
machines.  That, IMO, is what makes them perfect for this.  They're not
making a crappy machine and selling it.  They're eating their own dogfood,
and they're fixing their mistakes.  They've been doing that now for YEARS.
So it's a very refined design, and there's a reason that they're the so
popular.  They have auto bed levelling, automated nozzle cleaning, an all
metal hotend, geared extruder, heated bed, the list goes on .. it's
production ready.  The main problem here is their retail cost.  But they're
open source, and can be built from scratch, they even provide the BOM.

* lkcl mentioned that he's actually been in touch with Aleph Objects who
have offered to let him use their bot farm (
https://www.youtube.com/watch?v=v_jUObUGLTA)  to manufacture the parts.

* I mentioned that he should take them up on the offer immediately.  Deals
like that don't just fall into your lap that often (if ever).  That's
fantastic to even get offered a deal like that.

* lkcl says they run 0.5mm nozzles and he needs machines with 0.4mm
nozzles, because that's how he designed the parts.  I counter that he
should just have them print a full set of laptop production parts to see
what works and what doesn't.  The risk is low to try, and very likely, a
bunch of parts will print just fine.  Even if a few don't print well, those
can be done on a separate machine and at least the bulk of it got done on
the Taz farm.

* I mention that 0.5mm is better anyway for production.  The rule is to
print with as large as a nozzle as you can get away with .. no exceptions.
Every part should be optimized for this, from design onward.  He mentioned
that his design took quite a while to do, but I would say that you've
learned an important lesson by this.  Don't spend so much time designing
before you figure out how to produce it.  For reasons like this.  I speak
from experience here.  It's costly to make this mistake.

* Assuming the printed Aleph Objects parts don't come back OK due to nozzle
size issues, I would recommend asking Aleph Objects very nicely if they
could put 0.4mm nozzles on their machines (if not for free, then what would
it take them money-wise to swap the nozzles out for a short period?)  Being
that their printer farm is sectioned into old machines and new machines,
they're very likely running their daily stuff on the new machines, and
they've got some older slightly-more-finicky machines sitting in the corner
that would still print very accurately, that they're probably not using.
It would be cheaper to pay them to change the nozzles out than it would be
for you to eat the NRE of making new machines (not to mention your lost
time to design and manufacture them).  This is the smart choice.

* lkcl commented that the Taz design "wasn't rigid enough", to which I
called bullshit.  It's actually extremely rigid, I've used it, I have
experience with it directly, and I've seen what kind of prints it makes.
It makes fantastic prints, and it shouldn't be discounted just because it
doesn't look like a MendelMax.  I urge you to back up your assumption with
actual data before making accusations or assumptions.  Actual data, in this
case, is seeing how well those parts print on these machines.  That's the
litmus test.

* I pleaded with him to not "redesign" yet another 3D printer as was
proposed in the update post.  That's a waste of time, because that's
literally saying that there is not a single usable design out of THOUSANDS
of pre-existing 3D reprap designs out there.  Use something that already
exists, that's the best business decision and it's what's best for your
customers.  Wanting to re-engineer something because it's not perfect is a
classic sign of engineer-brain, which gets the best of us.  I get the urge
from time to time, but it is rarely the correct decision in times like
these.


* On the subjects of hotends, I recommended to stick to the tried and true,
I've had great experience with the Lulzbot v2 hexagon hotend, and the
J-Head.  I've had horrible experience with the Makerbot hotends (old and
new), and have had mediocre experience with the E3D -- it's finicky.

* On the subject of heated beds, I've had the most luck with Aquanet hair
spray on glass, heated to ~60-70C.  It allows me to swap the glass plates
out and minimize the time spent between runs.  This pays off in a
production scenario.  I had several dozen glass plates cut by a local glass
company, for under $4.00 USD each. I used regular old glass, no
borosilicate or anything.  Never had a problem, not a single one broke.
We'd take them out and throw the whole thing in the freezer if we were in a
hurry, they literally fall off the glass with no warping or anything.
Heated beds are a must for production.  Although there are different styles
/ techniques for bed adhesion, I say go for what you've used, what works.
Hair spray works for me, others do other stuff .. to each their own.

* On the subject of bowden vs non bowden setups.  I find that the speed is
limited by the extruder and hotend's ability to deliver melted plastic, to
the point where reducing the mass on the head doesn't matter that much.
Bowden setups in my experience complicate matters, and even when retract
settings have been tweaked, it's still hit or miss.  lkcl mentioned that he
recommended some sort of worm drive extruder that had a remote mounted
stepper or something like that.  As long as the extruder gear is mounted
near the hotend, that's all that I think really matters.  That's what
prints the best.

* On the subject of controllers (not mentioned on the call), the cheap
Arduino 2560's and RAMPS 1.4 with Marlin are just fine for production use.
Really, any controller is fine as long as it's a Cartesian machine.  The
new ones with ARM Cortex and fancy drivers are nice, but not required.  I
did it without the fancy stuff just fine.

* On the subject of designs / frames, building from scratch isn't that
difficult, this is the option that I took with our 3D printer farm.  I
recommended to take a puddle jumper flight to Shenzhen, go to the markets,
buy extrusion, screws by the bag, all that, and use Taobao for what's not
at the market.  It can be done, and literally everything on the BOM can be
delivered to your door in less than a few days, tops.  That's one thing
Asia's great for.  Cheap, fast, and good enough when it comes to RepRaps.
Our 3d printer farm costed less than $200 USD per machine, built from
scratch.  They worked admirably.

* On the subject of Chinese clone 3d printers.  The Monoprice machine is a
rebranded WanHao Duplicator i3.  Wanhao is a huge company in China, they're
making a TON of these things, mainly intended for the Chinese and Asian
markets.  Companies like Monoprice and others are approaching them to setup
distribution in Western countries.  They're actually not that bad!  I'm not
sure that they could be used for production, but they're better than you'd
give them credit for, and they're cheap.  Very cheap.  Not as good as a
Lulzbut Taz or an Ultimaker by any means.  But good enough that I'd buy one
just to have around.

* On the subject of whether or not Western 3D printer OSS companies are
dying or not.  The ones that are innovating are doing just fine.  Others,
like RepRapPro, are dying because they're not innovating.  Adrian Bowyer,
the founder of the RepRap project and was the owner / founder of RepRapPro,
is really solely responsible for his company going out of business.  While
all of the innovation was happening in the RepRap scene, he sort of turned
his nose at it and continued to sell machines with outdated technology.
His extruders were crap compared to what's been developed by E3D, Brian
Reifsnyder, Aleph Objects, and others.  For a guy that literally coined the
idea of evolution and self replication of machines, it's odd that he
wouldn't be more perceptive to integrating other's ideas into his
products.  He only has himself to blame.  Other companies like Prusa
Research, Aleph Objects, and SeeMeCNC are doing just fine, business is
booming.  While the Chinese machines are selling, there's still a lot of
activity and innovation happening right here where it all started.  The
Chinese aren't really seen as 'trusted' in the Western markets ... What's
crazy is, the most trusted brand in 3d printing right now isn't Makerbot or
some other closed source company.  It's an open source Libre company.
That's insane but true.

* On the subject of filaments.  lkcl's quote on the update post was: "And
no, using a network-3D-printing house is not okay, because the quality of
the PLA from such places simply cannot be trusted. It’s Faberdashery’s PLA
or nothing. I’ve shared some of the nightmare horror stories of low-quality
PLA with people on the list already."  So my experience is as follows.  I
literally ran 100+ kilograms of filament for our production orders.  You're
saying "Faberdashery or nothing", but I didn't use them and my prints were
just fine.  Faberdashery's filament are not magical.  There's nothing that
separates them from other filament manufacturers, other than their Pantone
color accuracy.  Other than that, it's pretty run-of-the-mill virgin PLA
that's been run on a decent extrusion machine.  The first step to good
filament is to start with virgin PLA.  Good PLA will come with a material
safety data sheet and will come from known sources, and will be "virgin"
aka not recycled / re-used.  Other than that, it all boils down to which
extrusion machine they're using, and how well they run it.  Good extrusion
machines will have several thickness sensors and will stop if anything bad
happens.  A well run setup will be able to do dozens or hundreds of KG's of
plastic before those thickness sensors go off.  A good modern roll won't
have any weird thickness inconsistencies, if it's made on a good machine
with a good operator.  There are now companies in China making decent
filament, although I can't name any names.  I could look this info up but
it may be a moot point depending on how the Aleph Objects collaboration
works out.  Anyway the point is that there are plenty of other companies
besides Faberdashery that make great filament.  And, I'd bet, ALL of them
would be cheaper.  HOWEVER, this is a MAJOR de-risking point for your whole
operation.  So use what's worked for you, if it's only a few thousand and
that's the difference between your operation running smoothly, and grinding
to a halt, then yea, use what you're comfortable with.


I also expressed my interest in the EOMA68 standard and how it may fit in
to several of my ongoing projects.  Mainly an open source laptop with a
mechanical keyboard and 20+ hour battery life, and a portable digital radio
system intended mainly for amateur / ARRL type stuff, but could also be
used by security researchers or anyone else wanting a powerful yet portable
SDR.

I'll hopefully be doing a more formal introduction on the mailing list
soon, to keep the topics separate.


That's about it.

Thanks,

Neil
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