Chain sprockets printed in 3D make e-bikes even quieter
The application at a glance:
- What was needed: plastic pinion
- Manufacturing method: selective laser sintering
- Requirements: high wear resistance, good sliding properties, long service life
- Material: iglidur® I3
- Industry: bicycle sector
- Success through collaboration: quick configuration of the component in the online 3D printing service, quieter operating noise than with metal
Would you like more information about the our 3D printing or do you need an individual consultation? Our experts will be happy to get in touch with you.
Problem
The standard metal sprocket made very loud running noises on the electric bike. The sprocket was the guide roller of the chain so that it did not touch the frame. The friction noises, however, made the e-bike sound like a tractor. Accordingly, Lars Hartmann set out to find a material that had the same running properties as the metal sprocket but was significantly quieter. Other requirements for the material were good sliding properties and a long service life, as well as high wear resistance when interacting with metal.Solution
In the context of his work for VMA Getzmann GmbH, manufacturer of stirring, dispersing, and fine grinding systems, he tested machine parts that igus had produced with its 3D printing service. The results were so good that Lars Hartmann considered the printed parts for his e-bike as well. It was the perfect solution for the hobbyist: "The standard metal pinion generates a lot of operating noise. We drew it and had it printed at igus from iglidur I3. Getting the part was simple and fast. We used the 3D printing service to upload the relevant data, chose the material, and ordered the quantity." The chain sprocket has been in used in two bikes for several months – and the noise level has decreased significantly, Hartmann is pleased to say.Optimum coefficients of wear and stability
The material in use, iglidur® I3, is of course also suitable for industrial application and mass production. It is especially attractive due to its low coefficients of wear and high stability and is processed with selective laser sintering (SLS).
In addition, igus® has developed the iglidur® I6 for particularly high demands with regard to wear resistance and for a long service life. In tests, the high-performance plastic beats machined gear wheels made of common materials such as POM and PBT. A worm wheel with 5Nm of torque and 12rpm was tested. The gear made from the iglidur® I6 laser sintering material exhibited minor wear after one million cycles, when the test was complete, and was still fully functional. That was significantly better than machined gears – POM gears exhibited total wear after 621,000 cycles, while milled PBT gears broke after just 155,000 cycles. Also part of the test: a gear made of the PA12 laser sintering material. Its high coefficient of friction caused it to stop after 521 cycles.
Easy to configure
At the same time, designers benefit from the igus gear configurator, which allows custom gear or chain sprocket configuration, even in unusual dimensions. In a few steps, the user needs only to enter the data for his gear (tooth module, number of teeth, width and inner diameter, etc.). This automatically generates a 3D model that can be exported as a STEP file. Uploading the file to the igus 3D printing service allows the configured gear made from the extremely durable iglidur i6 laser sintering material for gears to be ordered immediately. With one click, the user can order his gear (no minimum order quantity) or request a quotation. Within just three days, the custom-made part is ready for shipment.
