Replacement rudder bearing printed in 3D within three weeks achieves improved steering behaviour

• What was needed: a two-part rudder bearing
• Manufacturing process: selective laser sintering (SLS)
• Requirements: Split type, functionality in seawater, good fit
• Material: iglidur® i3
• Industry: Shipbuilding industry
• Success through cooperation: Fast production and delivery within 3 weeks, 20 times more cost-effective than the alternative made of seawater-resistant metal alloys, improved steering behaviour

The application at a glance:
The lower rudder bearing on an Albin Delta sailing boat was worn out and had to be replaced. However, it was not easy for the customer to find a replacement part, as the manufacturer of the boat has not been available for several years. In addition, the dimensions used in the original design are no longer common these days and with the split type of bearing, it is almost impossible to source an alternative spare part. Thanks to the online offerings from igus®, the customer was able to configure a bearing that met the requirements of the old bearing within two hours. After a short trade show, it was clear that the new bearing had significantly improved the control behaviour. Quote from the customer: "For me, this is a perfect example of how Industry 4.0 works. From the task definition to the actual solution of a highly customised design task, it only took 3 weeks and only 2 hours on the computer."

The rudder bearing of a sailing boat had to be replaced. However, the Albin Delta, or Delta 31, model from the 1980s has a special bearing, the type of which is split in two. The bearings are no longer produced in their unusual size and the manufacturer no longer exists. Looking for a ready-made alternative therefore proved to be almost impossible. Only a very expensive production of bearing shells from seawater-resistant metal alloys would have worked.

The customer found an inexpensive alternative at igus®. Using the online configurator, he was able to design the basic shape of the rudder bearing and download it as a CAD model. He then added further features to the model, such as a second flange and the pitch of the bearing, which is typical for sailing boats. He then ordered the finished model using the 3D printing service. A few weeks later, the replacement bearing arrived and after a short time, the customer was able to notice a massive improvement in the steering behaviour.

To ensure a stable steering behaviour over time, a rudder bearing with the perfect fit had to be manufactured. This proved a tricky task, as the rudder bearing was subject to a very individual fit due to its unusual dimensions and its division. By using the igus online configurator, the customer was able to design a plain bearing in a suitable basic shape with the correct tolerances. After a few adjustments, they chose the SLS method for production. Here, a laser selectively melts the SLS powder layer by layer in a powder bed. This process leads to very high dimensional accuracy, and, in combination with the iglidur I3 SLS powder, is perfectly suited for components that require high attention to detail with exact surfaces.

Alternatively, the customer could also have resorted to the customised production of bearing shells from seawater-resistant metal alloys. However, this would have been 20 times more expensive than a bearing made from high-performance polymers. The materials for 3D printing from igus® are tribologically optimised and are particularly suitable for applications with wear. For the application conditions of the rudder bearing, iglidur® i3 was suitable as a wear-resistant material; for more demanding and durable underwater applications, the igus® test laboratory recommends iglidur® i8-ESD (see diagram). undefined The 3D printing service from igus® not only offers SLS materials such as iglidur® i3 and i8-ESD, but also filaments and other accessories for the additive manufacturing of customised wear-resistant parts.

One of the biggest advantages of 3D printing is the freedom of geometry that comes with the tool-free process. The highlight of igus®: We use our own tribologically optimised materials, which are particularly suitable for printing wear-resistant parts. Thanks to the integrated solid lubricants, external lubrication is no longer necessary and regular maintenance becomes obsolete. This was the ideal solution for the speedometer of a classic car, both in terms of price and delivery time. The worn worm could simply be redesigned and printed. However, 3D printing is not only worthwhile for individual wear-resistant parts; the additive process is also suitable for series production.