There are several manufacturing techniques for plastic parts.Worldwide, injection molding services, 3D printing services, and CNC machining services are cutting, extruding, and molding plastics into usable parts.All these machines have unique advantages.
injection molding services
Injection molding services — the process of injecting liquid plastic into metal molds — are the most widely used process for making plastic parts, but alternatives such as vacuum casting and FDM 3D printing offer different advantages, providing designers and manufacturers with great flexibility.After all, different projects may require different types of machines.
However, in many cases, different technologies are used in different manufacturing stages.For example, 3D printing is often preferred for prototyping because it is simple, portable and has a very low startup cost.The injection molding services is often the preferred process for a large number of end-use parts because it is fast and highly repeatable.3D printing technology serves the development phase, while injection molding is responsible for production.
But what happens when you create a 3D printed prototype that needs to be produced through injection molding services?Given the fundamental differences between the two manufacturing techniques, how do you ensure that molded parts meet the specifications of their printed counterparts?How do you plan ahead to ensure successful prototyping and production?
Design injection molding services whenever possible
It’s not always easy to think ahead.When your first priority is making 3D printed prototypes, the natural instinct is to create the best printed parts, which means applying the DFM (manufacturing design) principles to the 3D printing process.
But if you plan to eventually move from 3D printing services to injection molding services, 3D printing prototypes must be designed to be not only printable, but also mouldable.
In practice, this means following injection molding design principles — even during the 3D printing phase.Should include drawing Angle, should avoid overhanging, sharp corners should be rounded.In addition, since molds cannot replicate complex filling patterns, complex filling patterns should be abandoned (which actually increases the strength and efficiency of 3d-printed parts) in favor of simple ribs.
Designing injection molding services from the start reduces the need for dramatic changes before production and simplifies the transition from one process to another.
Print using production materials
A useful prototype is not necessarily one that meets the highest standards of appearance and performance.On the contrary, the useful prototype is the one that best represents the end-use part, including its advantages and disadvantages.
That could mean making some compromises, including in the choice of materials.
Injection molding is a highly flexible process that is compatible with a variety of plastics, while 3D printing is more limited in terms of available materials.But when designing 3D printed prototypes, it is important to choose materials that match or at least mimic those used in the production process.
Importantly, this may not be the natural choice for a successful 3D printing job.Some effective molding materials are actually difficult to 3D print, requiring extra time and more thorough post-processing.However, selecting representative materials will yield prototypes that more realistically represent the final components, allowing a smoother transition to production.
Polishing prototype for “molded” surface treatment
For mechanical or aesthetic components, it is important to create a prototype with surface finish for the final component.Mechanical parts may require a degree of friction or smoothness, so prototypes with completely different textures won’t be particularly useful.(in addition, professional-looking prototypes can help companies market or promote their products.)
Thankfully, surface treatments can be used to transform the look of 3D printed prototypes.With professional polishing, the surface roughness of printed parts can be significantly reduced by using cloth or polishing wheel, and even a mirror-like luster can be produced.
The result is a 3D printed section that doesn’t have layers and rough textures and actually looks and feels like a molded section.
Beyond the FDM
FDM (molten deposition modeling) 3D printers are a popular choice for prototyping.It is cheap, easy to use and compatible with a wide variety of plastic filaments, which many businesses can iterate quickly by simply installing them in their offices.
That said, the parts produced by FDM 3D printing are very different from molded parts.The structural composition and surface finish are completely different, so FDM’s prototypes are not easily converted into molded parts.
On the other hand, more high-quality FDM substitutes can produce more molded parts.For example, PolyJet 3D printers can produce parts with strict tolerances and smooth surfaces, as can light-based processes such as slas.(a SLA, however, may only apply to aesthetic prototypes, as it can produce rather fragile parts.)
Seek expert advice
Obviously, one of the easiest ways to ensure a smooth transition between the 3D printed prototype and the final part of the injection molding services is to discuss the entire project with an expert.
If you intend to order the prototype through a professional service provider, be sure to let them know that the end-use parts will use the injection molding services.Better yet, use the same service provider for prototyping and production, allowing them to leverage expertise to connect the two processes.