Additive Manufacturing and the Bike Industry: Customization

One of the things Additive Manufacturing does best is customization. From patient-specific medical implants to player-specific Digital Foam hockey helmets, AM excels at bespoke designs. And in the bike industry, which has long been dominated by a handful of large-scale manufacturers, AM presents a lot of exciting options for small builders. Folks in the AM industry often reference “free complexity”: with 3D printing, there’s no need for additional tooling, fixturing, or process steps to add a feature to a part.? In fact, with AM, it’s more difficult for us to make flat, square, bulky features than organic, flowing, ornate ones — the opposite of traditional manufacturing.

One thing I have admired of the hand-built bike industry is the blurred line between art and engineering.? Often, the look of each bike speaks to its intended use, or showcases the distinct style of one of the 170 hand-built bike companies in the US, all without sacrificing ride quality or performance.

Take Hex Components, led by Ben Tew, for example.? They create custom bike components using ultramodern design software, smart modeling, and metal AM. The pictures above show some of their top caps, which lock in the front fork and handlebar to the frame. These were printed at our tech center here in Austin out of 17-4 stainless steel.? When asked why he turned to AM, Ben says, “3D printing offers a speed in creating new highly detailed design variants that can’t be matched with prototyping by hand.”? While Ben is a huge advocate for creating designs by hand, he still says that “when you really want that refined finish and accurate geometry on your parts, you can’t beat the speed of 3D printing.”? Through the use of computational design software, AM allows Hex Components to “quickly iterate on design ideas and go straight to final printed metal product.”? Ever since his college days, Ben has been utilizing 3D printing as a key part of the design process.? Having advanced degrees in mathematical modeling, while certainly an advantage, isn’t required to utilize 3D printing!

Riding in Austin, it wasn’t long before I heard the name Tomii.? Nao Tomii, of Tomii Cycles, is a local frame builder who makes some truly magical machines.? With the help of some mutual friends, I was able to connect with Nao and go visit his shop to discuss potential applications for AM.? It was incredible seeing his space and the extreme level of detail that goes into each bike.? Nao makes everything meticulously by hand, so I was a bit nervous that 3D printed components would take away from the art form.? Nao had similar concerns - he “wasn't that interested in 3D printing at first, but when [he] saw the samples, [he] was surprised by the high level of technology and wanted to make something.” Nao taught me a lot about the processes of designing and building bike frames, and together, our brains started churning with potential ideas.?

A lot of Tomii’s design aesthetic incorporates desert plants and landscapes, so it wasn’t long before we landed on the cactus badge.? One thing that was important to both of us was that whatever we did shouldn’t subtract from the handmade aesthetics.? The use of this badge, which would be challenging to make traditionally, with the tube-matched diameter and smooth edges, became a canvas for Nao to add his own personal touches.? I’m looking forward to seeing what other ideas/concepts he comes up with in the future!

?As I started diving deeper into the hand-built bike industry, I started to notice areas where AM could offer unique solutions.? One of those areas was the supply chain.? Looking at the different websites to order frame components, it became clear that there weren’t a lot of options for certain parts (especially US made ones).? Take fork crowns for example.? This part mounts the steerer tube (where the handlebar attaches) to the tubing that the wheels mount on.? It’s a complex part that has a huge impact on the bike’s overall look and feel.?

One of the main parts suppliers that builders use has less than 10 unique designs for cast fork crowns.? This really limits expression and customization.? Plus, handmade bikes are often custom ordered with each rider’s exact specifications, so this limited offering really restricts potential design opportunities.? If a builder wants to develop their own custom design with a casting house, they often have to put in a large order to make it economically feasible. For many small-scale bike builders, that math doesn’t add up.? For Ben, the lack of tooling required, and flexibility of AM is “great as it allows a small company like Hex to leverage a technology normally used by big companies.”

The crowns on the cover of this article are just some examples of what could be possible with AM. With proper Design for Additive Manufacturing (DfAM), fork crowns are an ideal candidate for 3D printing and can be a central feature in developing a company’s style.? Once a company sets up their CAD with full parametric control, they can specify all the necessary angles and dimensions, allowing for full customization with little hands-on manipulation.? If you are curious about this too, please contact me so we can discuss it and potentially work together!

The different CAD designs above were inspired by bike builders in my community. The cactus crown (middle) was designed with Tomii Cycles in mind. The crown on the right was styled for Sean Eagleton of Destroy Bikes in Portland, OR. On a ride with Sean earlier this year, he expressed interest in 3D printing and we stayed in touch afterwards. When he saw my design he was excited to get it on a bike. Last month at the MADE bike conference I was stoked to see my first part brazed onto one of Destroy’s featured bikes, and even better, to know 100% that no one else in the world has a fork crown like this one!?

One of the unknowns we had with printed components was how they would braze.? In brazing, you use a lower melting point filler metal to join two pieces of metal with the capillary action created by the small gap between them.? Talking with Sean, I found out that they usually scuff up two pieces of metal that are going to be brazed together to give something for the filler to hold onto.? So, with additive, it seems that the inherently rougher surface (compared to a machined part) actually works as an advantage!

These three use cases are just the beginning for AM, customization, and the bike industry.? Rapidly innovating, creating in small batches, producing locally where possible, adding differentiating design features, and further personalizing custom built bikes is just the starting point.? As 3D printing knowledge grows and spreads through the bike industry (EOS is here to help!), I have no doubt that the creativity and passion of the crafters will spawn all sorts of novel ideas and use cases for AM.

Cheers,

Spencer

Reach out at [email protected] if you have any questions/comments!

Article 1: My Bike Journey