What does it take to make a carbon wheelset?

Your bike wheels are one of the most important components of your bike; They are the only point of contact we have while driving. They are the best choice if you want to invest in a serious upgrade to your bike wheels. Additionally, a carbon wheelset is the best way to improve your riding experience. Ask a professional driver. They ride on a beautiful set of carbon rims. But have you never wondered how a carbon wheel is made? In this article we would like to explain how we make our wheels as simply as possible.

For most of us, carbon fiber manufacturing is a mystery, but for good reason. Companies invest enormous resources and development into their proprietary techniques. And that's exactly what we did; We are always looking for ways to develop new processes and offer you, our customers, new and better products.

CP 50 Disc

What is Carbon Fiber?

Carbon fibers have their origins in the aerospace industry. It consists of loose fibers of carbon atoms suspended in resin to form a solid material. Carbon fibers are fibers about 5 to 10 micrometers in diameter and are composed primarily of carbon atoms.

Carbon fiber rims are made of carbon fiber and epoxy resin. Molding a carbon fiber wheel involves placing prepreg carbon fiber pieces into molds. Prepreg is raw carbon fiber impregnated with an epoxy resin.

Carbon fibers have various advantages: high stiffness, low weight, high chemical resistance, high tensile strength, high temperature tolerance and low thermal expansion.

How is a carbon wheelset made?

The first step is to design the rim in our special 3D program. Here we can already calculate the carbon fibers we need and the shapes we need to lay the carbon fibers on.

To be precise, we source panels made from the highest quality carbon fiber, Torray T700 and T800 carbon fiber. This is also called prepreg carbon. Prepreg is raw carbon fiber impregnated with an epoxy resin. The second item we source is high quality bubbles. We chose these air bubbles because they create significantly smoother rim walls. Every batch of raw materials we receive is rigorously checked for any abnormalities using our DSC tester.

After the initial inspection, we stored the carbon fiber in our refrigerators at -5°C. We have to do this to maintain the activity of the resin.

The next step is to cut the prepreg to the desired lengths, shapes and angles (cut using our CAD controlled machine) and place the carbon fiber into our custom-made molds.

At this stage of the process, precision is important. Therefore, the layup is performed by hand by experienced layup staff. All wheel sets we offer have a document with a layup schedule that must be carefully prepared.

The next step will bring our wheelset to life: hot pressing.

Carbon must be cured at a precisely defined temperature, which must be constantly controlled to give it its strength.

Our hydraulic forming machines are specifically designed for pressure, temperature and time and are PC monitored to ensure we can always deliver top quality. Once heated, they are cooled and after demoulding we subject the wheelset to an initial rough machining quality control.

In the next step we have to remove the used air bubbles. We use a unique process to extract the air bubbles through the valve hole. The rim is then sent to our hole drilling machine. Here too we use a computer-controlled CNC drill that drills the spoke holes in the 4D direction.

We subject our rims to a secondary quality control to ensure that all holes are drilled correctly and the rim surface remains intact. At this stage we also check the roundness and flatness of the wheels.

The next step is to prepare our rims for a visit to our paint shop. Varnish covers and protects the carbon. Our experienced employees smooth out small unevenness and give the rim surface a special treatment.

In the final production phase, the wheels really come to life after painting and descaling. They are hand laced and trued by our wheel builders for final quality control. Our wheels are put through their paces one last time: forward stiffness test, lateral stiffness test, impact test to meet all ISO standards and more.

As soon as our wheelset has been approved by the inspection, it is recorded in our database; Each carbon rim receives a unique ID number. Now all you have to do is pack up our customized foam bags and send them to your doorstep.

I hope we've enlightened you and you've learned something about our carbon wheel manufacturing process without giving away too much of our magic.

Finally, let's summarize the process of making carbon rims.

1. Use carbon fiber material and air bubbles and a special material air bubble that creates smoother rim walls.
2. Applying a DSC tester to check physical properties;
3. Storage in refrigeration equipment to maintain resin activity;
4. Prepreg cutting, cutting into desired angles and shapes;
5. Precise layup and pre-modeling. Each rim has its own layup schedule documents carefully prepared by experienced layup staff.
6. Hot press molding, PC hydraulic molding machines with pressure temperature and time control;
7. Raw finish rim quality control (QC-1);
8. Remove the air bubbles through the valve hole using a unique process.
9. Drilling holes in 4D direction with a controlled drill;
Quality control (QC-2), checking and testing;
10. Smoothing, surface treatment by experienced workers;
11. Painting and Decalcomania;
12. Quality inspection (QC-3), 100% quality inspection and recording in the database, each carbon rim receives a unique ID number;
13. Packaging: Each carbon rim is packed in a customized foam bag;

To watch the video of the manufacturing process, click below.