You have a design ready to go, and now you’re looking for the next step to making your concept into a reality. It’s time to look at a rapid prototype in three dimensions to be able to show customers, new potential investors, and be able to make small adjustments to the design for better manufacturing.
What Is Rapid Prototyping?
Manufacturing a rapid prototype involves manufacturing techniques specializing in making precise physical representations of a three dimensional design or concept. The prototypes can be used for improvements with the design, the manufacturability, and with secondary processes. It’s a quick way to generate a sample for testing or as a proof of concept before full scale production begins.
What Options or Methods Are Available With Rapid Prototyping Samples?
Your design and product may have multiple pieces that include both metal and plastic. The great thing about rapid prototyping is that whatever the material you need, it can be accomplished quickly with economical means. These are many options available for your product samples, and more are being developed all the time:
Metal 3D Printing
Metal 3D printing is perfect for generating complex samples that need to incorporate lower weight and higher strength. It can create samples using hollow cavities or negative areas that decrease weight as it prints in layers in a matter of hours. Multiple metal options are able to be printed. No tooling is required to generate the prototype sample, which reduces the sample cost.
Stereolithography (SLA) was one of the earliest adopted processes for 3D printing or additive manufacturing for plastic. It is fast a technique for rapid prototyping, and does allow for complex internal designs features that aren’t possible with traditional manufacturing methods. SLA is a great option for low volume production parts for a quick prototype. They are made from a bath of photosensitive liquid that is solidified layer by layer with an Ultra-Violet light. The designed part is sectioned into layers by a computer and then these sections are created with the UV light passing through the liquid bath. Stereolithography allows for a finished part with a good quality finish and increased strength.
Selective Laser Sintering (SLS)
With Selective Laser Sintering, the design is completed one layer at a time using a laser to sinter a powder media. SLS can be used for plastic and metal prototypes, and it also allows for intricate internal designs that aren’t possible with traditional manufacturing processes. One potential drawback is that the surface finish is generally rough, so the finished parts may need additional work to smooth the surface if that is a finished product criteria.
Selective Laser Melting (SLM)
Selective Laser Melting is another option using powder media and is a process that can be using with intricate designs requiring very accurate details. The powdered media is welded onto a plate with a laser in a closed chamber. The most common powered metals include stainless steel, titanium, maraging steel, and cobalt chrome. SLM is the preferred option for parts requiring high strength, high durability, and a complex or intricate design. The prototype process is expensive and is usually kept for applications in automotive, aerospace, the defense industry, or in medical uses.
Digital Light Processing
Another option using a curing resin is Digital Light Processing. It is comparable to Stereolithography (SLA) prototyping. It passes a more common light source through resin to cure it, but it needs supports and post-build curing where SLA does not. It is faster than SLA, and be less costly than SLA also. It keeps a good tolerance to the initial design and has a good surface finish.
CNC machining is an ideal choice for creating rapid prototypes from plastic or metal without the need to invest in costly tooling. A big advantage is that you can hold tighter tolerances and a better surface finish than many of the other rapid prototype options available. It will create complex designs that also need threaded bosses and flat surfaces within a narrow tolerance window.
Fused Deposition Modeling (FDM)
If you think of the new 3D printing desktop versions people are using in their homes, these machines create by Fused Deposition Modeling. FDM melts a small plastic filament inside a printing nozzle and the machine deposits the melted plastic systematically layer-by-layer to create the finished prototype.
Advantages of using FDM include the low cost, the machines are easy to use, and you can use multiple plastic types and colors in one prototype. The trade-offs are a rough surface condition and low strength of the finished parts.
Rapid Injection Molding
If you plan to only make a few parts for testing, samples, or for design fit and finish, going with a costly final production mold isn’t the best way. A rapid injection mold that will only last a small amount of parts may be a low cost way to get the exact parts you need without the high cost of the final production mold meant for hundreds or thousands or parts. A low cost rapid mold won’t have the longevity of a final production mold, but when you don’t need it there isn’t a reason to pay for the high cost and long wait time.
Binder Jetting is a new process that uses many nozzles to fine droplets of a liquid binder on metal powder. Each layer of bound metal powder is compacted with a roller, then more powder is added on top for the next layer of the process. When the parts are done in the building process, they will be cured in an oven to burn off the binding resin and fuse the metal into a solid object. A big advantage of this prototyping process is that multiple parts can be made at one time, so it can be a mass production process potentially. The finished parts will not be as strong as the SLS process, but can be much less costly than some other rapid prototype options.
Laminated Object Manufacturing
With Laminated Object Manufacturing, thin laminates are laid layer by layer on a build platform. The lamination options can be paper, plastic, or metal. For each layer, a laser or another cutting device traces out the pattern for the layer and then the platform moves down by the thickness of one layer. The next lamination layer is glued on top and the process continues until all layers are complete. The finished product should be used for design that aren’t very complex, but LOM does not cost as much as many of the other options that require critical dimensional tolerances.
What option will be best for your project?
With these nine rapid prototyping options, the design and engineering can range from simple to complex. Each will offer advantages and disadvantages concerning cost, time to produce the product, strength of the materials, and the materials that can be used. No matter which material and process is chosen, one thing you can count on is that your design will benefit from having a prototype made to show potential customers, clients, and investors. When you’re ready to work with our elite team that produces world-class products, call (425) 339-0288 or email us at firstname.lastname@example.org.