Always eat pigeon with your antenna manufacturers

Added on July 27, 2015 by Spencer Wright.

Yup.

I was *not* good at this, by the way. The meat was pretty gamey, but actually had good flavor.

Planning for post processing

Added on July 20, 2015 by Spencer Wright.

The other day I got an email update from Rob Oliver, a machinist in Brooklyn who's helping me post process the EBM printed titanium parts that I got from Addaero recently. There's still a bunch of work to be done, but I wanted to write a bit about how we're thinking of the manufacturing plan - and the constraints that we're facing in the process.

While electron beam melting tends to produce much lower internal stress than laser powder bed fusion does, it's still a decidedly near net shape process. In further iterations I hope to get the as-printed part much closer to the final dimensions, but at this stage the parts I have deviate significantly from the intended tolerances. Specifically, most outer dimensions seem to have grown, most inner dimensions seem to have shrunk, and there are a number of locations where support structures have left unacceptable surface finishes.

My main focus right now is getting both inner diameters to within .006" of their designed size. It's difficult to get a reliable measurement of where they are now (due mostly to surface finish, and the presence of leftover support material), but they both appear to be about .040" undersized. In addition, I suspect that the shorter cylinder is slighly ovalized - though not to the extent that it'll be an issue in the end.

Although there are other conceivable options, the most obvious way to get the IDs within tolerance is milling. By using either a CNC toolpath on an end mill, or a boring bar on a conventional mill, it should be very easy to get well within .006" of nominal dimensions on both areas of the part. However, the issue of fixturing is nontrivial. I designed this part with T-splines, and its outer surfaces aren't orthogonal at all. As a result, we'll need custom tooling to hold the parts in a milling vise.

As an aside: Anyone who says that additive manufacturing eliminates the need for custom tooling has no idea what they're talking about.

In order to securely fixture this part, Rob is machining its negative into a set of aluminum blocks, which can then be clamped securely into a milling machine vise. This technique (which I'll refer to here as "soft jaws," although technically what we're making is more of a coped fixturing block) is used extensively in subtractive manufacturing to hold irregularly shaped parts.

The process of making soft jaws is relatively straightforward, but designing them for this part is somewhat complicated by the dimensional variation that EBM produces. Put simply, feature sizes in EBM parts tend to deviate from the design in the X and Y axes, but stay relatively true to size in the Z. That's because the Z axis is at least partly controlled by the Z stage drive system; the powder bed is lowered a predictable amount with each new layer, keeping features in the Z close to their designed dimensions. But in the X and Y, deviations in feature size are partly driven by the electron beam diameter, and partly driven by the distance that the feature is from the center of the build platform.

As a result, my part has grown anisotropically, and Rob will need (to some extent or another; soft jaws tend to be somewhat forgiving) to compensate for the as-printed dimensions differently in the XY plane than he does in the Z.

In the end, though, the most practical way of determining the final dimensions of the soft jaws is to make a set, test them on the as-printed part, and iterate as necessary. It's conceivable that the first try will work, and it's also possible that if we make the negative a bit too big in all directions, we could use a piece of soft material (for instance, blue tape) to take up the gap.

It's also worth noting that there's an alternative path that I decided *not* to take. A common way to make parts - both with additive manufacturing and conventional - is to design fixturing features into an intermediate stage of the part. These can then be used to hold the part while secondary operations are performed; they can then be removed in a subsequent step. I considered this option, but find it undesirable for the simple reason that it would likely result in more post processing steps. Worse yet, it would probably require the surface of the part to be blended where the fixturing element had been removed, which would be either labor intensive, or unattractive, or both.

Regardless, we should have the first iteration of our soft jaws machined shortly. Expect updates!

My secret Manufacturing master plan

Added on July 17, 2015 by Spencer Wright.

Background: My day job is directing Undercurrent's strategy work with General Electric, but on the side I spend my time researching the state of the art in manufacturing - specifically, industrial 3D printing. I've written before about my approach to some of this work, but want to lay out here the way I see it fitting into my career.

As you'll know from my blog (cf. one, two), a primary focus of mine is developing a line of high end metal 3D printed bicycle parts. However, it might not be clear that that's just one step in finding specific applications where 3D printed production parts make commercial sense. In the end, the purpose of my work is to help expedite the transition toward a more fluid, transparent, and efficient mode of product design, manufacturing, and distribution - one which properly accounts for its own externalities, and allows for rapid integration of feedback across and throughout a part's life cycle.

I should be made clear that my long term focus isn't specific to additive. Every manufacturing method has a purpose, and any claim that 3D printing is going to unseat other methods should be examined critically. I want product designers have perfect transparency into how a given process will affect cost and function, and to be able to tune their design such that it's well matched for the resources at their disposal - and the end user's needs.

I do believe, however, that additive manufacturing offers a unique and historical opportunity. Partly because of the fact that 3D printed parts always begin as 3D models - and partly, to be frank, because of its sex appeal - additive has encouraged a new wave of people to people to work in an industry (manufacturing) that was due for a radical change. And while the effect of their naïveté is often to simply create churn, in the end I believe that manufacturing will benefit greatly from the influx of new ideas and working styles.

In order to harness this opportunity, I'm focused on developing the most compelling possible use case for the technologies at play today. For metal 3D printing to reach industrial maturity, designers need to understand its limitations - and how to best exploit its strengths. So I have begun my research with metal powder bed fusion, which is currently the 3D printing process best suited for industrial use. I'm developing parts which make good use of 3D printing's strengths (lightweight, low production volume, smaller than a breadbox), and an industry which prizes the traits that additive manufacturing is best suited for (has short sales cycles, rewards innovative design, benefits from customization).

Today, developing metal 3D printed parts is an expensive process, and it's difficult to estimate how difficult a project will be. So to begin, an easy place for me to provide value has been to explain (in sometimes painstaking detail) the experience I've had over the past year and a half. Because there's so little public information about the realities of metal powder bed fusion, writing on that subject has allowed me to boost my profile quickly.

But more importantly, it has encouraged other people who are working on similar problems to offer collaborations. This has helped me twofold: First, it has in many cases resulted in decreased costs on my end, as the people and companies that I'm collaborating with have given me prototype parts in exchange for me writing long, in-depth descriptions of what they do. But even more significantly, these collaborations have given me unique opportunities to see past the marketing and sales messages and talk directly to the engineers who know the state of metal powder bed fusion best. This has allowed me to advance my own level of knowledge much more quickly than I otherwise could have, and has given me access to people who I can now turn to when I'm stuck.

To be sure, I have a *ton* to learn - and ultimately I'll never know as much as the seasoned professionals who I'm working with now. But between the hands on experience that I'm getting by building bike parts, and the access I now have to the most advanced research organizations in the world, I find myself in an ideal position to identify what aspects of today's manufacturing ecosystem most desperately need fixing - and who the most well positioned players are today. And that, plus the (I hope) sincerity, honesty, and intelligence that I've employed in writing about my own development process, puts me in a position to be a key part of whatever team ends up fixing them.

So, in short, the master plan is:

Build compelling 3D printed products.
Use the exposure I get from that process to learn as much as possible about the industry.
Use that knowledge to identify the biggest problems today, and find out who's best positioned to fix them.
Form like Voltron with those people, and together make sustaining and powerful changes to the way that the product development life cycle works.

Don't tell anyone.

ps - Hat tip to Elon Musk, whose strategy (and how he communicates it) rocks.
pps - I also explicitly want to bring more advanced manufacturing development to New York City, which I believe is the best place in the world to do serious work.

Wanting

Added on July 8, 2015 by Spencer Wright.

From a piece in The New Inquiry on the Women's World Cup, and how absent desire is from most women's public lives:

I never thought to put them together: that having role models who spoke to my extraordinary self-consciousness could have helped me reap the benefits of sports.

First: This piece is not about me, and I don't mean to make it about me. But I liked it, and there's something in it that really resonated.

As a kid I felt similarly self conscious, and had a really hard time expressing myself physically. It wasn't until well into my adult life that I felt comfortable trying at sports, but during high school an alternate physical activity presented itself: construction.

I began working on jobsites as a teenager. My dad was (and still is) a contractor, and he gave me a generous (I mean this sincerely) opportunity: I could start out like anyone else, as a laborer. My first summer in construction was spent largely in a basement crawl space, chipping cinder blocks out with a sledgehammer and then dragging the rubble upstairs, outside, and into a dumpster.

I loved it. It was the first time in my life where I had been assigned what amounted to a feat of strength, and there was no shame in me showing the signs of physical strain.

I think somehow that these experiences are directly related to the discomfort I feel about phrases like "hardware is hard." In my experience, basically everything is hard - if you're doing it right. It's something I've tried to keep in mind, especially as more and more of my identity has been tied to taking on big, challenging, physical projects.

Notes from Tesla's Fremont factory

Added on July 6, 2015 by Spencer Wright.

Today I had the pleasure of visiting Tesla's Fremont factory, where every single Model S is built. While they don't allow photos on the tour, I did take this pano to prove that I'm not fabricating the whole thing (but seriously though, a Google Image search does a decent job at showing you what it looks like inside):

Anyway, a couple of thoughts came to me on the tour, and I wanted to share them:

First of all, the whole place is an information overload. It's noisy (not at all unbearable, but still), and the tour is a whirlwind - the whole thing took just over an hour. Moreover, the entire building is filled with visual clutter. It's all stunningly beautiful, but there's just so much going on, and it's nearly impossible to see, analyze, and understand what you're looking at, what's being done to it, and which direction it's headed in the assembly line, before the train of golf carts that you're being dragged around in speeds off to the next thing. This is not meant to be a criticism of either the tour or the factory itself, and I'm sure an automotive engineer would have an easier time soaking things in than I did, but for the majority of the tour I struggled.
Lot of emphasis on sheet metal. Elon Musk loves his aluminum, and the tour itself is expressly directed towards the hydraulic presses that Tesla uses to turn rolls of aluminum sheet (from what the tour guide said, I suspect it's 16ga) into a car.
The tour also emphasized the economy that Musk/Tesla employs in building up their capabilities. The core story here is that American manufacturers (GM is called out by name, mostly due to the fact that they're the former owner of the NUMMI site, which you should learn about) don't want/need big equipment or industrial space in the US anymore, and so Tesla has been able to buy this stuff for a song. So the purchase of their largest hydraulic press (the biggest in North America); the decision to use a Lotus platform for the Roadster; Tesla's use of the factory itself; - all of these are described (not inaccurately) as shrewd financial decisions.
Interestingly, the only other brand names that get shout-outs on the tour are all Robotics companies: Kuka, ABB, and Fanuc. That fact - combined with the legendary stuff (all apparently real) about many of these robots having X-Men names - and the fact that the tour also highlights the human craft that goes into a range of sexy (and not-so-sexy) features of their cars - gave me the distinct feeling that Tesla consciously makes their industrial automation efforts seem as anthropomorphic as possible.
This has been reported before, and it's worth noting again: Tesla's current production is about 1,000 vehicles per week. In the NUMMI days, this same facility turned out about 6x that.
One thing that I was somewhat surprised by: Towards the end of our tour, the guide paused to explicitly note Tesla's purpose: To help expedite the move from a mine-and-burn hydrocarbon economy towards a solar electric economy. To be sure, I personally find this statement to be the most compelling thing about Tesla/Musk, if not the most compelling thing about any public company in the world (if you haven't read Musk's Secret Tesla Motors Master Plan, I'd really implore you to do so). But to hear it called out on a factory tour, to an audience which was made up almost exclusively of Tesla owners (besides a Tesla employee who had brought their family, I believe I was the only person *not* picking up a Model S right after the tour), seemed downright canny. Which leads me to my real observation:

Tesla is not, first and foremost, a manufacturing company; to wax on about the factory tour would miss the point. Their focus is simple: Musk has a singular vision for how the global energy lifecycle should work, and Tesla is doing whatever's necessary to bring it to fruition. Tesla is an energy company, and they're a "we're doing this because we believe in it and goddammit nobody else will" company. Which is really admirable, and it pleased me to see them use their factory - which, in spite of its relatively low throughput, is certainly a spectacle to behold - as a way to convert people to their mindset.

First EBM prints

Added on July 4, 2015 by Spencer Wright.

A few weeks ago I visited Addaero Manufacturing, one of the very few EBM (electron beam melting) service providers in the US. After my recent trials (and successes) with laser powder bed fusion, I wanted to try building parts with EBM. EBM is used extensively by aerospace and medical OEMs, but its penetration into the job shop world is way behind laser. Addaero, whose founders (Rich Merlino and Dave Hill) both worked at Pratt & Whitney before striking out on their own, is located just a few hours from New York City, and they were gracious enough to build two parts for me to evaluate the process.

I'll be writing up a longer post on the unique design considerations that EBM poses, but for now I wanted to share the pictures I took while there: