3D-PRINTED PARTS & KITS

Our high-tech, digital age has allowed small, independent manufacturers to create all sorts of products with lower development and production costs. In model railway terms, ready-to-run manufacturers have harnessed the benefits of 3D printing in order to produce new product prototypes at much lower cost.

The same technology has also revolutionised kit production. Instead of creating masters and moulds, modern kit makers are producing digital artwork instead. These computer files are then sent to a 3D printing machine, within which the object is brought to life via a jet of acrylic-based photo-polymer. When exposed to light, the material hardens, allowing the object to grow, layer by layer. Indeed, if you look closely at most 3D-printed objects, you can see traces of these individual layers on the surface.

To allow hollow or delicate items to be rendered, some printing machines also build up a supportive layer of wax, around which the polymer is then applied. Once the whole object has been created, the wax can then be dissolved in a chemical bath.

High-quality 3D printers are becoming more affordable, although online manufacturing portals, such as Shapeways, allow users to create their models without expensive equipment of their own. Parts can be scaled up or down (almost) at the touch of a button and products can be quickly made to order, so there’s no need to maintain stock levels.

In theory, if you can create the necessary computer artwork and have an internet connection, you can create almost anything. Moreover, the design process has been helped by a recent boom in 3D scanning equipment, which has been used to great effect by the likes of Modelu (MR274). Whether it be figures, individual detailing components or entire vehicle kits and lineside structures, the potential of 3D printing is boundless.

This may sound like a modeller’s utopia but, inevitably, 3D printing does have some limitations. The standard of 3D-printed components continues to vary and much depends on the skill of the draftsperson and

the quality of the printing machinery.

The material employed by the printer also has a bearing on the quality of the components. Some materials are better for recreating fine detail, but they can be brittle and difficult to work with. Others may present a rough surface that is tricky to refine. That said, the latest materials employed by higher quality printers is miles ahead in terms of resilience and texture.

While my early experiences with 3D-printed components left me sceptical of the medium’s potential, more recent products have been much more convincing. There’s no escaping the fact that the materials are very different from, say, plastic and brass, which are much more userfriendly. However, with 3D printing, most of the shaping and assembly is already taken care of, so much more effort has to be put into the finishing process instead.

Above: Older 3D-printed materials (left) and more recent, superior polymers. 3D printing now allows for the rendering of much finer detail . Above: 3D printing makes it easier to model more esoteric subjects that mainstream kit and RTR producers have ignored, such as this GWR ‘Pollen C’ girder-carrying set. These were produced by Hazelwood Models (MR193).

This set of 3D-printed parts for a ‘OO’ Metropolitan Railway Third class compartment coach was obtained a few years ago, from Matt Wickham’s Bluebell Model Railway Shop, via the Shapeways platform (www.shapeways.com/marketplace). These parts are still available, albeit in updated form, using the latest materials.

With the aid of 3D scanning and printing technology, Modelu’s figures feature an exquisite level of detail.