Mid-Life Cycling

Mid-Life Cycling

21 May 2018

Building in 3D

I guess we shouldn't be surprised.

On Friday, I wrote about a 3D printed airless tire.  When I learned about it, I knew that other 3D printed parts were being made somewhere. 

Turns out, I underestimated the speed of technological progress.  Now there's a 3D printed bicycle that looks like a sci-fi version of an urban commuter bike--and is said to be stronger than titanium.

The new machine was made by Arevo, a Silcon Valley (where else?) startup that specializes in "additive manufacturing" (tech-speak for engineering-level 3D printing).  The company is backed by the venture capital arm of the Central Intelligence Agency, which isn't surprising when you realize that the armed forces are the main drivers behind 3D's evolution from a novel way to make chintzy plastic figurines to a sophisticated technological process used to make weaponry.

(Few people realize that the Silicon Valley became, well, the Silicon Valley largely because of military contracts during the Cold War.  So, if you're going to thank a soldier or sailor for anything, make sure it's for making the iPhone possible, not for invading Iraq!)

The bicycle's frame was made first, as a single piece, and the other parts were made.  According to Arevo CEO Jim Miller (formerly of Google), it took about two weeks to make the bike.  

Knowing that answers the question folks like me ask about carbon fiber bicycles: "Why does something made of plastic cost so much?"  Well, carbon bike frames--whether of custom chassis from the likes of Land Shark or the Specialized items your local bike shop offers--are made by workers who lay, by hand, individual layers of carbon fiber impregnated with resin around a mold of a frame.  The frame is then baked in an oven to melt the resin and bind the carbon strips together.

Arevo takes workers out of the process.  It uses a "deposition head" on a robotic arm to print out the three-dimensional shape of the frame.  The head then lays down strands of carbon fiber and melts a thermoplastic material to bind the strands, all in one step.   The result is that Arevo can build a frame for $300, even in The Valley.  That is about what it currently costs to build a similar frame in Asia.

Of course, even though Miller is reportedly a cyclist, he doesn't see Arevo as the next Schwinn or Trek or Specialized:  The company is working on a head that can run along rails and print larger parts, avoiding the need of ovens in which to bake them.  "We can print as big as you want--the fuselage of an aircraft, the wing of an aircraft," he says.

Surely he knows the Wright Brothers started as bicycle builders...


  1. I don't think any soldier or sailor either of us is likely to meet had anything to say or decide about invading Iraq, or any other place. I WOULD, however, thank them for their service, even if it involved a war I'd rather wish we'd not gotten into.

  2. Steve--I would thank them for their service. In fact, I've done it, and even offered more--which they invariably refuse out of humility. I believe that no veteran should want for anything, even if I don't agree with the ways in which they were deployed.