A few pointers for plastic prototyping professionals and enthusiasts.
Prototyping forms an integral part of modern fabrication and manufacturing. A precursor to the final mass manufacturing process, plastic prototypes give a solid idea of the finished product, allowing manufacturers to tweak aesthetic and functional features until the desired final product is achieved.
With prototyping, a variety of materials including metal, glass, wood, and plastic can all be used depending on the desired product. In this piece however, we are going to focus solely on plastics and plastic prototyping, the various processes employed therein (with their advantages, use cases, and drawbacks), and the various kinds of plastics available for use (as well with their underlying use cases, strengths, and weaknesses).
Plastic prototyping is a broad field with a broad scope of underlying nuances, best practices, and varying techniques. In regards to the techniques in question, we have three major (vastly different) methods of plastic prototyping and they are rapid injection molding, 3D printing, and CNC machining. Each of these methods greatly differ from one another and with those fundamental differences come a few merits as well as drawbacks. This piece is going to contain a few tips that if followed correctly, should greatly improve your overall plastic prototyping output quality.
3D printing is perhaps the newest plastic prototyping method, employing technology that only a few years ago, were perceived as almost impossible. These days, 3D printing involves the additive molding of a plastic schematic design by an aptly named 3D printer. The printer is loaded with cartridges that serve as the building blocks for every print job.
Now here are a few tips for 3D printing. First, it is important to note that some materials work better than others do when it comes to 3D printing. PLA (or Polylactic Acid) is used in situations where the intended output is to serve little to no functional purpose, only aesthetics ones. Concerning more functional use cases, materials like Polycarbonate and Nylon are the preferred choices.
In addition, 3D printing is a low cost solution for low volume situations. This means that in situations when you intend to manufacture plastic prototypes in small amounts, 3D printing is pretty much a no-brainer choice. It is always important to understand the situations in which a particular method of plastic prototyping is best applied, especially in cases where one shop handles production lines that employ different work methods.
A popular fallacy that has somehow made the rounds is that CNC machining can only be applied for use on metals. This is far from the truth. CNC exists as a popular choice for plastics as well. One major advantage to CNC machining is that it allows the quick manufacture of high-fidelity prototypes. If efficient, expedient production is your preeminent focus, you need not go farther than CNC plastic prototype manufacturing.
With CNC, a prototype is cut out from a solid block or sheet of plastic. This differs from 3D printing in that unlike 3D printing, CNC plastic machining is a subtractive method. This means that bits of plastic are chipped off from the work material until the desired end product is reached. Products that are manufactured using CNC technologies have a more durable, structurally sound finish. This means that they can be applied to functional uses.
As such, in industries that require the mass-market fabrication of plastic prototype, whether as parts or as whole products, CNC machining is a great option. Important to note, however, is that CNC is more expensive than the other methods. The cost of purchasing, running, and maintaining the CNC machines can prove prohibitive for some.
Perhaps most important to note about this one is that it is by far the most extensively used method of plastic prototype manufacturing. A combination of underlying factors has made it such that injection molding has emerged as the best approach for a combination of use cases.
Injection molding is simple both in principle and in practice. Just like with metal, heated plastic is poured into a mold after which the resulting product is rapidly cooled, and final additions are applied.
It especially comes in handy in situations where the end products are required to possess structural rigidity, durability, and stress resistance.
Plastics are fun to experiment with build products from. In our world, the applications of various plastics have evolved from being the raw material for bottles and bowls, to the choice material for application in a variety of industries – from consumer gadgets to kids toys and electronic parts.
Whether an independent shop or a large machining factory, there is a demand for plastics for prototyping jobs and that demand is slated to rise exponentially in the coming years, as the global population experiences an unprecedented boom.