We introduced an international shower and bathroom brand to our plastic bearing capabilities and redesigned their shower door bearings to reduce assembly time, components and costs, improve installation, quality and durability AND add POS value to the product.


Our customer produces a number of bathroom products, sold largely to ‘big box’ stores across the globe, including over 2300 stores in the US. After introducing them to our capabilities, we could see scope for improving their shower doors with integrated shower door bearings that would reduce costs, simplify installation and provide consistency of quality and durability of the shower doors themselves.

The original shower door wheel assembly was out of sight of the user; functional rather than aesthetic, it had not been considered a priority for redesign. The shower door wheel assembly comprised an extruded runner, screw and commodity wheel, which were produced overseas and shipped to the customer for assembly in the US. The long strips of mass-produced extrusion was then cut to size and drilled with three holes for glass door levelling purposes. The commodity wheel was fitted to the centre of these three holes and the wheel attached to the glass panel via the others. The glass panel was then mounted on an extruded header track with a lip that retained it.

Consistency of quality, design for product life and POS improvements

The extrusion and components were often inconsistent and the drill holes imprecise, leading to issues levelling the glass doors during assembly and installation.

The BNL plastic bearing solution, is fully assembled and injection-moulded. Injection moulding ensures accurate, repeatable holes in the mounting plate for fixing, and reduces tolerance requirements previously needed to combat abnormalities in the aluminium extrusion. The integrated design means fewer bought in hardware components, and so less associated costs for the customer and less assembly steps needed for a simpler and more consistent process.

Our customer was concerned that a design using plastic components would not hold the heavy glass doors. This was not a concern for us – at BNL, we use 50 years plus of proven bearing design techniques to match or exceed the needs of our customers’ specifications. Our bearing wheel is designed specifically to handle the load of the glass door (with a recommended safety factor), and in fact, it surpassed the requirements. Under testing, it withstood the load of a glass door at 78kgs not just for the intended life of the product, but remained intact, with no cracking, permanent deformation or loss of function, far in excess of the customer specification.

The nature and geometry our design also improved the durability of the system for the end user. When fitted with the BNL bearing, the doors are ‘anti-jump off’, i.e., the glass door cannot fall off the rail. The previous solution required an additional part to be fitted for the customer to class the system as ‘anti-jump off’ at point-of-sale. The BNL bearing design gave our customer a point-of-sale improvement over the previous design.

Collaboration for innovation

Collaboration is key. We support our customers with VAVE services, engineering, design and testing resources. We always aim to add value to our customers’ product and to expand our customers understanding of the potential capabilities of plastic bearing design. Our customers are often surprised by the operational improvements BNL’s plastic bearing designs offer, including advantages via component, assembly and weight reductions.

Overall, for our shower door customer, BNL were able to prove to the customer that by using our bearing design techniques, plastic can be a match for metal equivalents, whilst also improving value, installation, quality and durability of the product.

Find out more about our shower door bearings and how integrated plastic bearing design can add value for you.