Accurate, consistent & cost-effective ball splines


Ball splines provide linear motion where accuracy and speed is required, such as in robotics, automotive half-shafts and drills. They are a type of rolling element linear guide bearing, where ball bearings run along a track on the axis of a shaft in a cage or retainer.

Machined plastic cages often need additional production work to finish them, such as trimming excess plastic from them . We injection mould our ball spline cages, to produce parts that are consistent, accurate and do not need extra production operations. We have less material waste, faster manufacture and can offer high volume, consistent output of cages to our customers. Our production methods also allow for thinner wall sections than those achievable through machining, so our ball spline cages are lighter and used where space in the assembly is at a premium.

We can also offer a flexibility of design that machined ball spline cages cannot. We have designed ball splines to meet functions they may not usually be associated with, for example, integrating them vertically in instrumentation and control applications to create a push function. In these instances, we can also design and integrate features and mating parts into the cage to reduce the component count and save space.


Other reasons for choosing a moulded plastic ball spline cage are:

  • Cost-effective production methods in comparison to machining
  • Moulding uses less plastic for a lighter, better value product
  • Chemical and corrosion resistance of plastic versus metal
  • Reduced friction and heat for less wear and longer operational life
  • Less noise, vibration and harshness (NVH) in the system

We offer a machine tear down service if you would like to discover whether your products could benefit from a BNL ball spline.

Discover more about our moulded plastic ball splines and cages.