Plastic AM gearbox prototype gives superb results
Smart Manufacturing Technology (SMT) is an international engineering company with their design headquarters based in Nottingham, UK. They were approached by a client to design a 5 speed gearbox for city buses. A totally new concept incorporating SMT patented design features, the new gearbox was designed and optimised in-house using MASTA, Solidworks, CAD and Ansys.
A full size functioning model of the gearbox was required to check that it would assemble as designed, package correctly in the confined space of the bus chassis, and also allow the customer to have a ‘hands on’ appreciation of the new product.
To have a prototype manufactured from actual materials would have incurred huge expense and a long lead time, so an alternative had to be sought.
SMT had previously used 3T RPD for smaller models built using their plastic Additive Manufacturing process, and were very impressed with their service and the quality of the parts. Therefore SMT had no hesitation in turning to 3T again to produce the full size prototype model of the gearbox.
Because of the size of the gearbox casings (approx. 552x488x709mm) SMT had a slight concern that 3T’s AM machines wouldn’t be able to accommodate them. However, 3T have some of the world’s largest plastic AM machines, and they built the parts in one piece without any problem.
Dennis Redmond, Chief Automotive Engineer of SMT says “The finished product was outstanding and the level of detail on the more intricate and complex parts was very impressive. The benefit of having an actual prototype model in our hands allowed us to make small design changes that were not evident on the CAD software, before the go ahead was given to commence full production of the gearbox.”
After being assembled and checking that the design functioned as intended, the gearbox was presented to SMT’s customer. It took them a while to realise that the parts painted silver to signify aluminium castings were actually plastic and to fully appreciate just how ‘true to life’ the housings were.
Such is the quality of the finish of the plastic AM part, the gearbox is now kept on display in SMT’s visitor reception area. Redmond summarised by saying “We will most certainly be using 3T again to turn SMT’s future design concepts into functioning prototypes”.
Smart Manufacturing Technology Ltd