Scroll down to find out more about individual processes that go into building your dream bike.
5.26.2020 – Words by Ben Farver
Make it, break it, do it again. That pretty much sums up our testing protocol over the last three months. When the Argonaut team and I decided to take all composite production in-house it became apparent that robust and comprehensive impact and fatigue testing capabilities would be imperative.
There are a few bicycle testing labs across the US that do an excellent job, and using one of these labs would be a more economical solution. The downside is time. A testing protocol takes exponentially longer using a 3rd party primarily due to transit time. A single frame takes at least a few days to get to the test lab, then tested, and a few days back in the best case scenario. When testing multiple frames those days waiting for crucial data quickly turn into weeks and even months.
Our R&D process has three legs, each critically important for developing new product. Design, engineering, and testing. During the design phase Steve Domahidy creates the ideal form. He then works with Mike Olson to engineer the tooling. Following that comes the layup design for the part, again done by Steve. Once we have a prototype part, we try to break it using either a destructive impact test or cycle fatigue test.
Our test lab has two impact tests made by Chris Fitzpatrick that meet the ISO, or International Organization for Standardization, criteria for falling mass and horizontal impact. The falling mass test is intended to mirror the forces of a rider in a head on collision, and the horizontal impact mirrors the forces of a rider dropping from a high curb or ledge.
ISO 4210-6:4.1 Falling Mass
ISO 4210-6:4.2 Falling Frame
Impact tests are great for making sure that Argonaut road frames are structurally viable and safe. Equally important is the validation of long term viability. Our fatigue testing machine is a thing of beauty, built by LiTeM and imported from Italy. With this machine we perform ISO 4210-6:4.3 that mimic pedaling forces, ISO 4210-6:4.5 vertical weight of the rider, and ISO 4210-6:4.4 for the horizontal stresses the rider puts on the frame. Each test is at least 50,000-100,000 cycles, and the forces of each cycle are the maximum the frame would expect from a very large, very powerful rider once or twice during a long ride.
LiTeM Cycle Fatigue Fixture – performing pedal fatigue and horizontal fatigue tests.
We built this test lab to make sure that first, our frames are safe, and second, so that they’re reliable. Argonaut road bikes will last a lifetime. I know this because we put our frames through a lifetime of abuse here in our lab.
Perfect Custom Carbon Bicycles
5.19.2020 – Words by Ben Farver
For those that read last week’s Tech Tuesday titled Back to Tubes , I bet you thought we were going back to Tube to Tube style construction. Ha! Really?? No way, no how. The technology we’ve developed to make the frame junctions is unlike anything currently being done in the bicycle industry. To be honest, the composite technology most widely used to make bicycles is fairly antiquated. It is our goal here at Argonaut to utilize the most advanced technologies from the broader composite industry to create the best carbon fiber bicycle frame possible. In the case of the frame junctions, we’ve even created our own patent pending process.
The goal in making any composite part is high compression, the elimination of air bubbles or voids, and fiber orientation control. To accomplish this with our frame parts we’ve invented a unique twist on an existing technology called trapped rubber molding. Trapped rubber molding consists of laying plies of carbon on a silicone mandrel, then placing the carbon wrapped mandrel in an aluminum or steel cavity. When heated the silicone expands creating an immense amount of pressure while the resin in the carbon cures. Sealing the mold keeps the resin from being squeezed out of the part and pressurizes the entire system, creating a 100% void free finished part. Because the plies are laid on a mandrel mirroring the final internal shape, there is zero fiber distortion. High compression + void free + no fiber distortion = perfect carbon fiber frame part.
The use of trapped rubber molding technology also allows us to be much more vertically integrated, controlling every process save for actually making prepreg carbon. The key technological advancement that happened between the time I started making carbon frames and now that makes trapped rubber molding on a small, custom scale possible?… 3D printing. Before 3D printers became so accessible and accurate the mold to make a silicone mandrel could only be CNC machined. Using a 3D printer, creating silicone mandrel molds is viable on a low volume, custom scale.
The new Argonaut road frame will be offered in either pre-designed or custom geometries. Every Argonaut has a custom layup pattern based on the size, power output, and riding style of the individual rider. For those whose touch points on the bike line up with one of our pre-designed geometries, their build starts with selecting their layup pattern and molding their frame parts with tooling, or frame molds, that has already been machined. Their frame junctions are laid up on the correlating silicone mandrel.
For custom geometries, we actually cut new, custom frame tooling. This is unprecedented in the bicycle industry. No other company machines a set of molds with the actual customer’s name on them. The corresponding silicone bladder molds are printed in our 3D printer, and the silicone bladder is created by injecting liquid silicone into the cavity.
Trapped rubber molding using 3D printed mandrel molds is the only process I’m aware of that can create a perfect, custom frame part. Every other process involves some sort of compromise, whether it be quality of construction or design / geometry limitations. Our new molding technology has no limitations and makes no compromises. Perfect, custom carbon bicycles.
Back to Tubes
5.12.2020 – Words by Ben Farver
There are many ways to make a bicycle. Each modality of construction is either driven by efficiency of construction or the material being used – and sometimes both. Steel bikes were originally brazed, but now mostly TIG welded. Titanium can ONLY be TIG welded, that is unless you’re Bruce Gordon and decide to make a lugged Ti bike, but I’m fairly certain he’s the only one that has pulled that off.
Photo : Red Kite Prayer article Bruce Gordon in two bikes.
For a long time the goal when making carbon fiber bikes was to mold the largest, most continuous frame section possible in order to maximize the amount of continuous fiber in the frame. That is, carbon strands that are intact and uninterrupted. However, with the increasing use of unidirectional carbon fiber and complex layup schedules, continuous fiber has become less of a primary focus. Sure, it’s not good to carelessly cut or interrupt fibers, but it is possible to do so without a deleterious effect on the overall structure.
The original Argonaut carbon road frame was made in a similar fashion as most high-end production carbon frames. That is, we molded complete frame sections and bonded them together. For example, the top tube, head tube, and first 1/3 of the downtube were molded as a single piece. The primary advantage of this style of construction is being able to closely control the layup schedule through the frame intersections.
The bladder molding consists of laying carbon on a latex bladder, then placing that carbon wrapped bladder in an aluminum, clamshell mold. The mold is heated to cure the pre-impregnated carbon while the bladder is inflated to compress the layers of carbon together. A high amount of pressure is necessary to compress the layers of carbon in order to produce a high strength part. The bladder is inflated to about 220 psi, and nearly eliminates all voids, or bubbles between the layers of carbon. The key word here is nearly. An undersized or poorly made bladder can result in dry spots on the surface of the part, or worse, an inter laminate void.
Original Frame Section
It is the goal here at Argonaut to build the perfect bicycle. Perfection is a journey rather than a destination, and the next step in our journey is the pursuit of perfect frame parts. A perfect frame part has no voids, no imperfections, and every strand of carbon stays where intended. This brings me to the new modality of Argonaut frame technology – tubes. Tubes, bicycles, and new are three things that don’t really go together. An assembly of tubes has been the basic, primary structure of a bicycle frame since the beginning. It is our pursuit of perfection that brought us back to this most basic component. This picture says it all.
Flawless inside and out
New tube on the left and original frame section on the right.
Right?! Isn’t that crazy? These parts look like a different material altogether relative to their bladder molded cousins. Our new method for making tubes is a molding process called differential expansion. Rather than relying on an inflatable latex bladder, we’re laying plys on a Delrin, or resin plastic, mandrel. When heated the Delrin mandrel expands inside the aluminum cavity creating compression. When first put into the mold, the carbon and mandrel fill up the cavity completely, leaving no room for the fibers to be distorted or wander. The entire mold is sealed using silicone piping and o-rings. When heated to the cure temperature of 250*F, the silicone seals the mold and the entire system pressurizes. The Delrin expands and creates an enormous amount of pressure inside the mold – upward of 600 psi. This amount of pressure has an effect on air bubbles like pulling a balloon to the bottom of the ocean. Any air trapped between the layers of carbon, like the air in the balloon, is compressed to the point of disappearing entirely. The result is a100% void free, perfect part.
Finished flawless tube in the mold.
Delrin mandrel on the left in one half of the mold and a finished tube in the other half on the right.
The desire for perfect frame parts is what drove our decision and development of this molding technology. Next week, I’ll get into how we make the junction areas that complete the frame.
4.28.2020 – Words by Ben Farver
The thing that truly sets carbon fiber bicycles apart from their metal cousins is the ability to manipulate the material in a way that yields inconsistent flex characteristics dependent on the direction of force. If I’ve already lost you, sorry…. this Tech Tuesday is going to get granular. But that’s what you’re here for, right? I’m sure the kids are quietly doing their schoolwork and you’ve already got most of the cooking for the day prepped and ready to fire, so why not do a deep dive into the physics of composite bicycles?!
Carbon fiber components, from a layup standpoint, are made in two different ways. One, resembling metal, is done where each layer of carbon lies perpendicular to the layer below. Or, the individual strands can be woven together at a 45 degree angle. A component made in this manner yields a part with uniform flex characteristics regardless of the direction force is applied. The flex characteristics of the carbon component are isotropic, or the same in every direction. A carbon tube made in this way will behave just like a steel or titanium tube, flexing consistently regardless of the direction of force.
Uni-Directional Carbon Fiber rolls at zero degrees F.
Carbon starts to set itself apart when the angle bias between the strands of carbon is something other than 45 degrees, creating an anisotropic structure. Anisotropic structures flex differently depending on the direction of force. When the angle bias between the layers of fiber is changed to something other than 45 degrees, flexural strength is increased when force is applied in one direction, and decreased when applied from another.
The vast majority of carbon fiber bicycles are now made using uni-directional, pre-impregnated carbon fiber. Unidirectional means that all the strands of carbon on a single sheet, or layer, are going in the same direction. Pre-impregnated means that the carbon sheet has already been saturated with epoxy resin catalyzed by an increase in temperature. Our carbon, or prepreg for short, is stored in a big freezer at zero degrees F to keep the resin from curing.
Stay with me here… our bicycle parts are made using individual layers if unidirectional carbon fiber built layer by layer over a rigid mandrel, or slightly shrunken version of the finished part. The layers are cut in specific, pre-determined shapes that, when assembled and cured in a mold, yield a part strong enough to endure the forces exuded yet flexible enough to work in concert with the other parts of the frame.
The shapes of the individual pieces of carbon sheet is referred to as the layup pattern. The layup pattern comes as a result of the most important part of a carbon fiber bicycle’s design, the layup schedule, which is the cross sectional angle orientation of the individual fibers. For example, there are nine layers of carbon in one version of our down tube. Each layer is cut out of a unidirectional sheet of carbon at a different angle, and laid on the mandrel in a specific order. The order and orientation of the fibers is the layup schedule. The corresponding shapes of the individual plies is the layup pattern.
Autometrix plotter that cuts the patterns.
The layup schedule is the key factor that determines the flex profile of a frame section, and the ability to tune this flex profile in an anisotropic manner is where carbon excels relative to its metal brethren. The term “vertical compliance, horizontal stiffness” is nearly a cliche in carbon bicycle advertising copy, but that phrase actually describes what carbon fiber bicycle frames can do fairly well. By carefully engineering the layers of fiber within the frame it is possible to build a bicycle that is very stiff when forces are applied in one direction, yet fairly flexible when applied from a different direction.
Each ply gets a number for the layup schedule.
The down tube section of a bicycle frame carries the most impact on ride quality. We look at the flex characteristics of the down tube from three different directions: vertical, horizontal, and torsional. Vertical stresses are acted out by the weight of the rider, and horizontal and torsional stresses are acted out by the pedaling force of the rider. Every Argonaut is made with a custom layup schedule, and subsequent pattern. We design the down tube, and every other part of the bike, with a layup schedule and corresponding pattern so that the bike is sufficiently stiff to propel itself forward under rigorous pedaling forces, yet also suck up bumps and road vibration for a comfortable ride. Engineering the carbon fibers within the frame in this manner is the only way to successfully tune the ride quality specific to the owner.
Individual carbon plys. Note the different angles of the uni-directional carbon.
Long story short, making a carbon fiber bicycle frame with a deliberate, specific layup schedule throughout is a giant undertaking, and creating custom layup schedules (AND patterns!) even more so. But, it’s totally worth it. The juice is absolutely worth the squeeze. No other way is it possible to make a bicycle with this kind of ride quality. That is, a bike that is an absolute joy to ride.
Thanks for reading.
4.21.2020 – Words by Ben Farver
Creating a design in a computer, whether it be a bicycle or piece of furniture, is like designing a puzzle. Whoever’s job it is to turn that design into a physical thing has to solve that puzzle. The better that person is at solving puzzles the faster they’re able to make the physical thing with fewer tools and better use of material. This is effectively the relationship of the machinist to the designer. The designer makes the puzzle, and the machinist solves it.
We’ve got a big CNC machine, or computer numerical control, to help execute the solution quickly and reliably, but Mike, our machinist, still has to tell the CNC the most efficient way to turn design into reality. First, Mike has to figure out how to hold the part he’s going to machine, which is otherwise known as work holding. Often times he has to machine a completely new part, or fixture, just to hold the part he is trying to make in the desired position.
CAD Model with the Designer.
Our CNC machine works on 3 different axis: X, Y, and Z. The table moves on the X and Z axis, and the cutter moves on the Y axis. To maximize the efficiency of the machine Mike wants to physically touch the part as few times as possible because every time he has to touch the part, he has to stop a program, remove and re-fixture the part, then start another program.
Tooling paths in software.
At a very high level, Mike goes through three primary steps in machining a part. First is the work holding, which can involve CNC operations as well. Next he creates the tooling paths, which is to determine the sequence of cuts and the cutting tools to perform the operations. These operations range from taking out large chunks of material to tiny, fractional amounts of material that create a finished surface. Mike will often run through a program virtually in the computer to make sure there aren’t any errors or mistakes before running the program. The one thing a machinist wants to avoid is called crashing the machine. To crash the machine is to run the tool or the tool holder into either a fixture or the part being made, usually with tons of force. It sounds like a car accident. There are very few safeguards on a CNC machine. If you tell it to slam the cutter into your vice, it will gladly do so potentially destroying whatever tool it is holding or the spindle itself. After making sure all the tooling paths are safe and clear, he’ll go ahead and run the program keeping an eye on the operations to make sure everything is going as planned.
Having a quality, reliable CNC machine and a good machinist is absolutely paramount to Argonaut operations and critical to making new frame parts in a short amount of time. The time it takes to make an individual part is fairly similar between good machine shops. The big difference is the time to create a part, make necessary revisions, and so on. It is the ability to make multiple revisions with very little lag time that makes having a CNC machine and operator in house so beneficial.
Being able to machine our own molds sets us apart in the bicycle industry and puts us among only a few bicycle companies with this capability.
Thanks for reading.
WTF is CAD??
4.14.2020 – Words by Ben Farver
CAD, or computer aided design, is a term thrown around a lot, so I thought it pertinent to dive into what CAD design is, and why it is so important when it comes to making Argonaut bicycles. One of the primary reasons that the look of a bicycle has evolved from relatively straightforward, two triangles with round tubes, design to the wild, swoopy, flowy surfaces we see now is the broader industry’s move from metal to carbon fiber frames.
’96 GT track bike by Cycling Tips
James Huang’s article about the design of the GT superbike
The fact that carbon cannot be welded like metal tubing requires that the frame be made in an alternative way. It is possible to glue round carbon tubes together and reinforce the joint areas with additional carbon. However, it is more common that sub-sections of the frame are molded in a halved metal cavity and bonded together. In order to create the mold that makes an individual frame part, like the front triangle or just the head tube portion of a bike, a computer model of the finished part needs to be created. That computer model, or CAD design, is then used to create the metal cavity, or mold. Frame molds are often referred to as frame tooling.
CAD Model of a Head Tube.
Head Tube out of the computer and in the tooling.
Good computer aided design is really the most important part of the whole carbon fiber bicycle manufacturing process. Not only does it control the final aesthetic of the bike, but there is such a thing as good CAD and bad CAD. A bad CAD file ends up being a nightmare to work with. If the designer doesn’t properly blend the surfaces or builds the model poorly, the drawing will crash or be unreadable to the program that runs the CNC machine. And that’s just the usability side. Just as detrimental is CAD design that fails to be aesthetically pleasing.
The Argonaut road frame was originally designed by Zach Hilbourne at Utensile in Portland, OR. I spent many hours working with Zach to refine the design of the frame – Zack patiently letting me poke at his computer screen and making errant hand gestures like a spastic kid pretending to be an orchestra composer. I’m proud of the design we landed on, but it wouldn’t have been possible without his excellent CAD design skills.
Thanks for reading.
Behind the Curtain
3.31.2020 – Words by Ben Farver
SOPWAMTOS – NAHBS 2019
A quick history lesson for those that aren’t familiar….. when I switched from making steel frames to working with carbon I didn’t have the expertise or equipment to make carbon frames at the level I wanted. I got very lucky when I found an outstanding supplier just up the Columbia River from my small shop in Portland – Innovative Composite Engineering (or ICE) based in White Salmon, WA. It was with the help of ICE that I developed the first Argonaut carbon road frame, and from 2012 on we have had a great relationship. I am extremely grateful for everything that Steve Maier and the team at ICE helped me accomplish and taught me over these last eight years.
Walk-in freezer for prepreg storage.
It has always been my dream to own my own composite production and control every step of the manufacturing process from mold design and machining to laying up composite frame components.
Today, the Argonaut team and I are ready to pull back the curtain on everything we’ve been working on for the last year. Our “showroom” here in Bend that we debuted last summer is actually much more than that. The front space is where we receive customers and build complete bikes, but the back is where the magic happens. Equipped with a walk-in freezer for prepreg storage, an Automatrix automated plotting machine, and a HAAS VM-3 CNC we are now a fully functional composite manufacturing facility controlling every aspect of the Argonaut bicycle from design to final assembly.
HAAS VM-3 CNC
Automatrix automated plotting machine
Over the next few months we’ll be doing a deep dive into every aspect of our manufacturing process, revealing all the painstaking work that goes into an Argonaut custom bicycle. Next week I’ll introduce the team that makes this possible. Stay safe and stay healthy, and by the time we get back to Weekly Rollout and pictures of purdy bicycles hopefully the world will look much brighter than it does today.
Behind the Curtain
Thanks for reading.