Every year, a bunch of articles appears on the Internet that a three-dimensional printing prototype will produce another industrial revolution and destroy the usual mass production.
The near-technological public is already beginning to get tired of these praises. According to experts, the disappointment is caused by the gap between the capabilities of technology and market expectations.
However, this applies to consumer 3D printing, which is not of high quality and limited to plastic. Industrial printing, for all its high cost (both equipment and materials), has been used for a long time and is relatively successful.
What is a 3D printing prototype?
3D printing prototype is a layer-by-layer technology for creating an object based on a virtual 3D model. 3D printers are computer-controlled, work with digital three-dimensional models and produce objects by adding material – in contrast to milling, which removes the excess.
Therefore, 3D printing is also called additive from the English add and direct digital manufacturing. Today it uses polymers (including plastics), model clay, cellulose, metals, wax, living biological cells and other materials.
Three-dimensional printing technology was invented by an American engineer Chuck Hall in 1984.
The method is called “stereolithography”. Hull patented his invention and founded 3D Systems, which began to develop the first 3D printers. This made Chuck a millionaire.
Pros and Cons of 3D Printing Prototype
+ Quick check of product design and ergonomics.
+ Cheap production of prototypes and small series.
+ Individualization of production – easy and cost-effective creation of customized products (for example, for a specific patient).
+ The ability to create truly complex objects – mechanisms, products with a complex internal structure and bizarre geometric shapes.
+ Non-waste production – almost all the material goes into products (which are also created on order and do not roll around in a warehouse waiting for the buyer, like the products of ordinary serial production).
– Low productivity compared to traditional casting and stamping (due to which 3D printing is not competitive in mass production).
– Technical restrictions on the size of the product (usually up to 20 cm, maximum – up to 50 cm).
– Economic restrictions on the volume of production of the party (usually up to 100 pieces).
– The high cost of industrial printers and supplies, especially for metal printing.
– The quality and durability of products are inferior to milling and molding from plastic.
Professional 3D printing prototype companies typically combine 3D printing with milling (which has also become digital a long time ago).
And some combine 3D production with casting in silicone molds. Three-dimensional printing is best suited for prototyping, and milling for small to medium series production. Milling is advantageous when producing hundreds of products, but can not cope with complex geometry, like 3D printing.
More recently, the process of creating a prototype of the product was incredibly long – up to several weeks, or even months, but nobody canceled the progress, and today the technology of rapid prototyping, or 3D printing, allows to create samples of almost any object in the shortest possible time. Such a concept as a digital prototype, obtained by designing a 3D model in various CAD systems, is now surprisingly few.
The first RP systems appeared in the United States in the early 90s of the last century. These were bulky, complex and very expensive machines that required special working conditions and were very inconvenient to operate.
Technology has evolved, and around 2000, the so-called 3D printers began to appear. These RP-systems take up less space, can work in a normal office environment and are much easier to operate.
The general principle of operation of such devices is the construction of a model in layers. The digital model obtained from 3D-CAD is divided by software into thin flat layers and sent to the printer.
The printer builds, or, as they say, grows the model layer by layer until it is completely finished. Thus, from a technological point of view, various RP systems differ mainly in the method of constructing a flat layer, the material used, and, of course, the thickness of a separate layer.
It is believed that all RP-systems, to one degree or another, use the technology of additive synthesis – the model is obtained by adding the individual layers together.
From this point of view, the machining technology is subtractive, because with it, in order to obtain the final product, excess material is removed from the workpiece.
From here follows one of the main advantages of rapid prototyping systems – the ability to build models with completely arbitrary geometry. It is possible to layout a model of absolutely any shape into layers, and, unlike machining, the time and cost of production will be determined only by the size of the model, not by its geometry.
3D Prototype design
Imagine that you have developed a three-dimensional model of a new product, such as a television remote control. To reproduce it, earlier you would need to transfer the drawings from the CAD system to the technologists, then prepare a mold or other equipment for this product – only after that you could create the first prototype of your remote control.
Thanks to modern technologies of 3D prototyping, today it is enough to transfer the created model to the desired format, and then send it to print, and in a few hours, you will receive a ready-made prototype.
This is one of the most common ways to use any three-dimensional printer – the ability to quickly and easily switch from a 3D-CAD model to a prototype that you can hold in your hands is hard to overestimate.
In printers, it is possible to use a variety of materials, ranging from translucent polymer and polypropylene, including matte hard materials of various colors, to elastic materials with a high coefficient of deformation to rupture.
Ready-made prototypes are easily glued, painted in any color, they can be coated with a thin layer of nickel or chromium by electroplating or vacuum spraying.
The transparent material can be painted in volume. All this allows to quickly get a prototype, which will not differ from the final product, not only in appearance but also by touch. These 3D printer capabilities are widely used for preparing demonstration samples for customers and exhibiting at different expos.