3D Printing Your Way to Custom Replacement Gears

What was needed: replacement gear for a tractor motor
Production method: selective laser sintering
Requirements: high wear resistance, good sliding and mechanical properties
Material: iglidur I3
Industry: utility vehicles
Success from the collaboration: manufacturing costs are one-tenth of those for conventional production methods, complex part made in one piece, improved abrasion resistance

The application at a glance:
the igus cleaning team uses a tractor for such work as gritting and transport. The gear serving as a starter for the tractor's motor was so worn out after a while that the tractor could no longer start. The manufacturer was unable to provide a replacement, so the tractor remained out of service. After about six months of inactivity, it was to be scrapped. However, shortly before it was, the 3D printing team intervened and was able to trace the worn and broken gear and print it within a matter of hours. The tractor now works reliably again thanks to the gear made of iglidur I3, which has significantly better sliding properties and greater wear resistance than the previously installed gear made of conventional plastic.
 

The replacement gear made of iglidur I3 is considerably more abrasion-resistant than the gear made of regular plastic

Problem

Often, it is not as easy as one thinks to obtain replacement parts from the original manufacturer. This was the case here: the manufacturer of the tractor, which the igus cleaning team used for various jobs, such as gritting the site, was unable to provide a new gear. The broken gear operated as starter for the large drive pulley of the motor. The load acting on the gear every time the engine was started was too high for the component made of regular plastic, so that it soon wore out and broke. Therefore, a special gear was required that fitted exactly, was wear-resistant and had good sliding properties.

Solution

The 3D printing team tackled the problem and was able to design a drawing of the original gear by using the broken one. This was converted into a STEP file and then printed via selective laser sintering with iglidur I3. The tool-free 3D printing cost €28 per piece, which was ten times more cost-effective than mechanical production, which would have amounted to more than €300. For additive manufacturing, the special shape of the gear with the spindle geometry in its interior is no problem. Furthermore, the printed gear promises a longer service life compared to the previously used gear due to the higher abrasion resistance of the material. The tractor was saved from scrapping and could be used again in its full functionality.

3D printing for special parts

3D printing offers unparalleled design freedom, enabling the creation of complex shapes in a single process. This technology is ideal for producing bespoke or obsolete replacement parts, providing a practical solution when traditional manufacturing can't deliver. It's particularly cost-effective for small production runs, as it eliminates the need for expensive tooling and reduces material waste. For instance, producing a single gear for a tractor through conventional means might exceed €300, but with 3D printing, the cost can be reduced to just €28, demonstrating the economic benefits of additive manufacturing.

The replacement gear with the spindle geometry in its interior was ready to use within just a few hours of printing

Simply configure gears yourself

igus offers different options for printing a gear. For example, design engineers can configure the required gears with the igus gear configurator and then order them from igus directly. Find out exactly how this works here. Alternatively, an existing CAD model can be uploaded in the 3D printing service and commissioned with the appropriate igus material and manufacturing method.
 

Configure your gears easily with the igus gear configurator

Calculate gear service life

At the igus testing facility, a variety of load examinations are conducted to ensure the dependability and utility of their online tools. Every product undergoes rigorous testing, simulating real-world conditions to validate their performance. Among these tools is the gear lifespan calculator, designed for gears crafted from iglidur I3 and iglidur I8 materials. It assesses their durability based on the specific demands of the application. This tool simplifies the process of determining material compatibility for your unique needs and predicting the optimal time for gear replacement to prevent unexpected failures.

The service life calculator takes all sorts of test results into consideration to ensure a precise indication of the predicted gear service life