Video: Take a look inside a Canyon
German manufacturer using technology normally found in the hospital to get a detailed look inside carbon
So how do you tell if the top end carbon frame is as good on the inside as it looks from the outside without cutting it in half, which rather spoils the frame? The answer, for Canyon at least, is a CT (Computed Tomography) scanning machine which they're now using in both development and quality assurance. At about £300,000 it's not a cheap bit of kit but it gives Canyon a non-destructive way to look inside their frames and forks to see what's really going on.
"We're pretty sure we're the only company in the bike industry using a CT scanner," they told us at the show. "It's a level of technology that's only really been used in medical and research facilities up to now. It's helped us produce a new carbon frame, which in the medium size is 790g, that we're confident we can make consistently in high volumes without taking any risks at all with rider safety."
Computed Tomography, is a large number of individual X-rays computed together into a three-dimensional visualisation of an object. The process allows hollow objects to be very accurately mapped, so it's ideal for bike frames and forks. "CT is the only way you can really tell what's going on inside composites with any degree of accuracy, without cutting a component up and physically looking inside," they said of the process. "We're using our CT scanner both in the design process and also as a quality assurance tool. As of now, 100% of Canyon's carbon fibre forks are X-rayed before they're sent out. That's to ensure quality and to make sure manufacturing tolerances are met. If a fork breaks it can have a pretty significant impact on the rider. This isn't about wanting to avoid a lawsuit, it's about peace of mind for both Canyon's owners and the people that ride their bikes."
A full CT scan of a fork would be made up of over a thousand separate X-rays; that process takes around 15 minutes, and computing and analysis time needs to be added to that. That's too big a job to undertake for every production fork, so at the moment Canyon are using the CT scanner to take a series of six X-ray images of different views of each fork to check for voids, cracks and uneven wall thicknesses. A fork scan takes about three minutes and all the X-ray images are stored for reference.
Canyon are also using the scanner as part of the development process for new products. CT allows you to check the manufacturing process against the CAD files of a product to make sure that the factory is making the thing you've designed. Using the CT image and the CAD image overlaid allows the Canyon engineers to check where the actual product differs from the specification. "Everywhere you see the CAD drawing, there's not quite enough material, and if you see the CT scan then the physical thing is slightly bigger. What you really want is a mix of the two, where they match perfectly. It's very small tolerances, and with such a complex shape to measure this is the only way of really knowing how well the finished product matches up to the design.
"Where you have two bladders that join, if one of the bladders infates too quickly you can get a big wrinkle; that's extra material for a start and it's impossible to know how it's going to affect the structure. Also, if you have extra material somewhere then it's missing somewhere else. You put in so much and it needs to be in the right places. CT allows us to check that the manufacturing process is as accurate as it can be.
"It's also useful in the testing stage. Say you get your carbon frame and you pass the EN tests and our own standard that goes above that. You don't actually know if the frame is okay, it might be just one load cycle away from failing. If you can take a detailed look at the material inside you can decide that you're not happy with things, even if the frame has passed. We have so much more information available thanks to this process."