While 3D printing is additive in nature, building layers one on top of the other, another frequently used technology in rapid prototyping is CNC, which is subtractive in that it mills away layers of material, instead of adding them, to build parts.
But there are many times that these two technologies go hand in hand when manufacturing parts, and CNC machining is often used to finish 3D printed parts. One of China’s most experienced rapid prototyping companies, WayKen Rapid Manufacturing, specializes in both.
Over 60 employees work for the company, which is located in Shenzhen and provides its customers with many different kinds of rapid prototyping technologies, including SLA and SLS 3D printing, CNC machining of plastic and metal, vacuum casting, and rapid injection molding.
One application that frequently uses both 3D printing and CNC machining is automotive prototyping – we frequently hear about 3D printed car parts, both interior and exterior. But CNC machining is more often called upon to manufacture automotive lighting components, because it’s difficult to hide the layer lines that 3D printing leaves behind in clear components like lights and reflectors.
“We are focusing on Automotive Prototype as a complete service which has allowed us to expand our knowledge and experience in this area,” WayKen wrote. “From proof of concept design reviews and mechanical component engineering test to Show Car projects, From exterior lighting prototypes to interior component prototypes, we are able to support at all levels.”
CNC mills can handle the post-processing required by most 3D printers, and can also produce stronger parts at a more rapid rate of speed.
The benefits of using CNC machining in automotive manufacturing include error-free productivity, as numerical control can ensure efficiency and simplicity, low labor intensity due to high levels of automation, multi-axis linkage, high precision, and excellent consistency. Applications in automotive prototyping provided by WayKen include 3D data and design verification, loading, reliability, and performance tests, low-volume customization, and limited-run trial production.
As WayKen offers machining acrylic and polycarbonate services, one of its particular specialties is automotive lighting prototyping, including automobile reflectors.
“Automotive development is one typical example which small initial quantities are needed for validation procedures,” wrote WayKen Project Manager Tony in a company blog post. “This critical demand is no doubt great challenges for parts manufacturers. When clients come to order a few dozen pieces, it’s often hard to respond, which is why auto suppliers frequently have to turn to custom machined solutions. Traditional, long-lived standard tools are expensive and are generally not viable for small batch production situations that require only low-volume demands. Professional rapid prototyping companies tend to be the fastest to understand the needs of designers and provide customized machining services to meet the needs of small quantities or even a single part.”
CNC machining is the perfect technology for developing aluminum reflectors, which are typically used in higher end automobiles and can be challenging to manufacture – not only does this clear component play an optical role, but it also helps to enhance the overall appearance of the vehicle.
“For auto parts, rapid prototyping manufacturers often offer a variety of processing options for different needs,” Tony wrote. “Things like 3D printing (additive manufacturing), Urethane casting(silicone moulds), RIM and rapid tooling.”
Aluminum reflector prototypes require a mirror gloss and good surface roughness, typically lower than Ra 0.2 μm, and the accuracy requirement needs to be controlled within or below 0.05 mm. WayKen says that CNC milling is really the best option for machining these components, as the technology provides high precision and quality surface finishing, though 5-axis CNC machining is necessary to finish the complex structure.
WayKen also used aluminum in a project that required CNC machining to manufacture RC car parts. Durable but soft, aluminum is the most widely used non-ferrous metal, and is highly corrosion resistant and lightweight.
The metal is an excellent conductor of both heat and electricity, and is a good reflector of visible light and heat, which explains why it’s often used for automotive reflector prototypes.
The company uses Aluminum 6061, Aluminum 6061-T6, and Aluminum 5083 grades for prototype CNC machining, though it also offers Aluminum 7075. In addition to automotive reflector prototypes, WayKen also uses aluminum to CNC machine various components for drones, robots, and unmanned aerial vehicles (UAVs).
WayKen’s multiple manufacturing technologies are used for several different applications, such as design and engineering verification, functional and working prototypes, low-volume manufacturing, prototype concept models, and visual presentation prototypes.
Discuss this and other 3D printing topics at 3DPrintBoard.com or share your thoughts below.
[Images provided by WayKen Rapid Manufacturing]