Are you looking to add a subtle yet eye-catching decorative element to your metal component? Look no further than brush finish! GMN specializes in metal decoration, and one attribute we commonly add to metal is a mechanical brush finish.
What is a brush finish?
Performed at the front-end of the manufacturing process, a brush finish consists of many unidirectional lines creating a clean, consistent blanket over the surface of the metal. Applied to either stainless steel or aluminum, brush finish is often combined with other decoration enhancements such as ElectraGraphics, embossing, and screen printing, to name a few. Used in a wide range of products, brush finish is particularly prevalent in the electronics, home appliances, and automotive industries.
The metal brush finish process
As you can see in the video, sheets of raw metal are fed into a machine having a large abrasive brushing wheel over it. The brush creates many fine linear abrasions on the sheet, reflecting light in a unique way. There are many design options to consider as well, including selecting a brush texture ranging from fine to heavy or applying the finish to the metal overall or selectively. For selective finishes, a resist ink is screen-printed onto the metal sheets before the metal is brushed. The resist protects the desired area from being brushed, thus creating an interesting contrast within the design. The contrasting look results solely from the difference in the textures and the way light reflects off of the surface.
After brushing, the metal sheet is washed and dried to remove any residue or oil, and then an operator quickly inspects the sheet for any apparent defects as it continues down the line. A roll-coater can also be set up to apply a tinted or clear coating in-line onto the metal to enhance its durability or appearance. In the video, a tinted coating is applied to the aluminum to make it look slightly grayer. Since stainless steel can be more costly at times, this is a cost-effective way to make aluminum mimic the appearance of stainless steel.
Finally, the sheets go through an oven and are again visually examined for any imperfections. This final inspection marks the completion of applying the brush finish, and the metal is now ready to move onto the subsequent process.
Brushed metal finishes at GMN
To catch a glimpse of the various looks that can be realized with brush finishing and see the brush finish line in action, you can watch our video below.
A spin finish, also known as spotting or engine turning, is a mechanical metal decoration technique that creates visually striking and repetitive circular patterns. The unique interplay of light as it reflects off the finished metal surface adds movement and enhances the aesthetic appeal of the part. Rising to popularity in the 1920s and 1930s, the spin finish was frequently seen in the automotive industry, especially on dashboards and instrumentation panels. However, in recent times, this decorative finish has expanded its reach to include a broad range of industries such as aerospace, appliance, electronics, and more.
The spin finish process
Primarily performed on aluminum or stainless steel, a mechanical spin finish is always applied on a flat sheet of raw metal. The metal sheet is first lubricated with oil to facilitate uniform spinning and prevent the burning of metal when the abrasive pad is applied. The abrasive pads are mounted on single or multiple spindles that descend on the flat surface to skin the metal in a circular, overlapping pattern. The extent to which the patterns overlap each other can be easily adjusted and altered.
Types of spin finishes
The two types of spin finishes that can be applied are:
- Drag spin finish - Once the spindle(s) descends on the metal, it literally drags across the surface while continuously blading the metal and creating overlapping swirls.
- Spot spin finish - Once the spindle(s) descends, it blades the metal from a targeted spot, ascends, and then descends again on a spot next to it, creating overlapping or isolated patterns.
The computer numerical control (CNC) spin finish machines at GMN can hold up to seven spindles at a time, and the diameter of each spindle can vary from a minimum of 0.5” to a maximum of 20”. The distance between each spindle and the speed at which they travel across the metal surface can be customized to achieve different looks. Depending on the design intent, the swirling pattern can range from fine, to heavy, to coarse. Spin finishes can also be applied overall or selectively. For selective finishes, a resin is screen-printed on the metal, which protects the desired areas from the abrasive pad, thus creating contrasting looks within the design. Offering a range of sizes, depths, and pattern intensities, the cosmetic variations that spin finish can produce is truly vast.
Once the spin finish is applied, the metal sheet is run through a washing line to remove the oil from its surface. The sheet is cleaned, dried, and a clear or tinted coating is applied to the surface of the metal. As a subtractive process, the spin finish takes away the inherent protective layer from the surface of the metal, and hence adding a topcoat is extremely crucial to seal the exposed metal for performance considerations. The sheets are visually inspected and then are ready to be formed into the desired shape. Decorative accents such as lithographic, screen, digital, and pad printing, along with embossed or debossed graphics, are often added to spin finished parts to further accentuate their aesthetic appeal.
With decades of custom manufacturing experience and printing capabilities under its belt, GMN has worked with several leading companies including Dell, Ford, Callaway, General Motors, Keurig, and Fiat Chrysler Automobiles to create stunning spin-finished nameplates and components.
To see the spin finish process in action, watch the video below.
Land Rover is a luxury British automotive company of predominantly four-wheel drive, off-road capable vehicles, owned by multinational car manufacturer Jaguar Land Rover (JLR). In a joint venture with Chery Automobile Co., their assembly plant in Changshu, China, has been manufacturing Jaguar and Land Rover vehicles since October 2014. GMN China has been part of this supply chain since 2015, supporting the airbag emblems on the steering wheels of Jaguar and Land Rover vehicles.
In the continuous push for localization, Land Rover China collaborated with GMN China on the front grille badge of its 2nd generation Land Rover Evoque (L551), a model built for rough terrain and extreme weather conditions. In addition to the cosmetic requirements, the front grille badge had to pass stringent exterior automotive specifications set up by Land Rover that demanded testing to the highest performance standards.
The grille badge was created with mirror-finish aluminum that was screen printed with Land Rover’s corporate color (British Racing Green). A subtle emboss was applied to the perimeter of the letters, followed by a thin doming on the badge. These processes, along with the mechanical spin finish on the aluminum badge, rendered an understated luxury finish.
Ultimately, GMN China’s proprietary topcoat ensured that the badge successfully passed the following performance tests and requirements -
- Filiform corrosion test on the aluminum substrate (11 days)
- Neutral salt spray test (42 days)
- Cyclic corrosion test (42 days)
- Accelerated weathering (50 days)
Matching up to Land Rover’s slogan, GMN China went “Above & Beyond” from prototyping through full-scale production to deliver a custom solution that met Land Rover’s needs. The partnership with GMN has put in place a domestic manufacturing solution for Land Rover that doesn’t require them to source components from overseas manufacturers. The exterior grille badge has been in production on the L551 assembly line in the Changshu factory. There are evolving plans to bring the badge onto other exterior usages and global Land Rover platforms.
The automotive badge is a prime example of GMN’s total solution to successfully integrate various processes to create a unique look for our customers. To learn more about our automotive capabilities, visit our website or schedule a consultation with our experts.
From enhancing the visual characteristics of a part to shielding it from environmental damage, protective coatings have become a vital part of metal fabrication and finishing. While there are several different ways to apply a coating to metal, one of the most efficient and commonly used methods is roll coating.
Roll coating is the process of applying a base, intermediate, and/or topcoat coating to a flat substrate with a series of rollers. But how exactly does roll coating work?
What is the process behind roll coating?
Roll coating is a process that uses three rollers to apply a coating to a flat substrate: a soft application roll, a highly polished steel roll, and a metering (or doctor) roll. Firstly, the substrate travels between the soft application roll and the steel roll. The application roll picks up the coating as it rotates, and subsequently transfers the coating to the flat sheet of metal as it passes through. The metal sheets are then transferred to an oven where the coatings are baked and cured.
Roll coating offers a few benefits over other metal coating technologies. When applying a coating to a flat metal substrate, ensuring that the coating is deposited uniformly with the exact required thickness is critical. With roll coating, the amount and viscosity of the liquid deposited on the substrate can be precisely controlled by the metering roll. The closer the metering roll is to the application roll, the thinner the coating, and vice versa. This makes roll coating one of the most precise coating methods currently available.
Another reason why roll coating is so frequently employed is that its deposition time tends to be faster than other coating technologies, such as spray application or screen printing. In addition, the coatings used can help protect metal from harsh environments while enhancing ink adhesion prior to any embossing or other finishing steps.
What makes roll coating at GMN unique?
To meet a variety of project needs, GMN has two roll coaters; one that does direct roll coating, and the other that can do both direct and reverse. Reverse roll coating works roughly the same way as direct, the only difference being that the application roll rotates in the opposite direction of the substrate’s travel. Due to the different travel direction, reverse roll coating can apply a thicker coating than direct. This additional coating thickness is useful when the design intent requires a greater depth of color and environmental durability.
GMN’s coating family includes acrylic, polyester, and urethane coatings, each offering a different level of thickness, malleability, and resilience against heat and UV radiation. Each coating employed at GMN is custom formulated by our chemists to meet a wide array of project needs.
At GMN, we have years of experience using roll coating for products in a variety of industries, such as automotive, appliance, and personal care. To learn more about GMN’s custom roll coatings and how they can help your next project, schedule a consultation with our experts.
Tooling a part to size remains integral to the metal fabrication process. While there are several tooling possibilities including steel-rule and rotary die-cutting, laser and water jet cutting, and compound tools, which method do you employ for efficiently performing multiple operations on a metal component? The answer lies in our video below. By offering a peek into the functioning of progressive dies, the video clearly illustrates the many advantages of utilizing progressive die-cutting to drive productivity.
Progressive stamping process
To cement our understanding of progressive die-cutting, let’s dive deeper into the Nissan automotive badge featured in the video. Made from aluminum, the badge requires a flat, coiled metal strip to undergo blanking, pre-forming, forming, lancing, debossing, and cutting. If we were to perform each of these operations individually with separate stand-alone tools, it would not only be tedious but also time-consuming and expensive. Progressive die-cutting, also referred to as progressive stamping, is an effective and efficient way of performing multiple operations under a single die set. A die set comprises of multiple individual dies (or stations) that sequentially perform the desired processes on the metal. The minimum and the maximum number of stations in a die set are dictated by the design and part geometry.
Progressive die-cutting fabrication process
The fabrication process begins with mounting the die set on the stamping press and feeding the metal in a coil or sheet form to the press. Registration marks or holes on the metal allow for its precise alignment with the die’s progression. Even the slightest misorientation of the substrate with the die set can negatively impact the entire output and hence, remains a crucial factor in the die-cutting fabrication process. As you can see in the video, the press progressively transfers the metal sheet in the web from one die station to the next through an automated feeder mechanism. The six individual dies in the die set perform the following functions:
- Die #1 - Cuts the outer circular shape of the badge
- Die #2 - Lances the part to relieve the metal, thereby preventing it from being deformed in the later stages
- Die #3 - Pre-forms the middle portion of the badge
- Die #4 - Pre-forms the edges of the badge
- Die #5 - Cuts out holes from the center of the badge
- Die #6 - Debosses, forms, and cuts out the badge, all at the same time
At the end of the progression, the web and finished parts are separated from one another by a lance operation, and the final parts slide down a conveyor belt. An operator at the end of the belt inspects and organizes the output. Once the progressive die-cutting process is completed, the Nissan badge undergoes anodizing and pad printing. Anodizing is an electro-chemical process that converts the aluminum surface into a durable, corrosion-resistant, and high-energy surface. Pad printing, an offset printing technique, transfers black ink into the recessed letters of the anodized badge.
Advantages of progressive die-cutting
Suited for high production volumes, progressive stamping is particularly favored for its efficiency and reduced cycle times. The form, profile, and size of the part play a critical role in determining its fit for progressive stamping. This cutting method is ideal when project volumes are high and registration requirements are feasible.
To watch the progressive die-cutting press in action, watch our video here.
In the manufacturing landscape, die-cutting is an indispensable fabrication process used to convert a wide range of materials into specific shapes and sizes. Whether you wish to utilize a custom-shaped silicone foam into a gasket, require a panel filler for a medical device, or simply need to cut out labels and adhesives, die-cutting allows you to efficiently cut materials in large volumes with increased consistency and accuracy.
While there are several die-cutting methods such as laser cutting, water-jet cutting, and rotary cutting, our video below offers a glimpse into steel rule die-cutting, one of the most common cutting methods utilized at GMN.
Steel rule dies and clamshell die-cutting press
Made of steel, the die is formed by bending, curving, cutting, and shaping a straight steel rule in the required pattern. Once the rule is mounted and secured on a laser-cut wooden board, the die is ready to use. The lead time to make a steel rule die ranges between one to three days, depending on the complexity of the design.
Steel rule die-cutting is typically performed on a clamshell press. Comprised of two platens – one stationary and one movable – the press in different tonnages can support varied sizes and materials. As seen in the video, the die is installed on the stationary platen and the material to be cut is placed on the movable platen.
The precise alignment of the material is ensured with one of the following ways:
- 3-point registration system - This consists of two grips to hold the material in place and one guide mark to accurately align it with the die.
- Pin-register system - Pre-punched registration marks on the substrate itself that can be aligned to the die position.
The movable platen is pressed against the stationary one to complete the cutting process. Although most of the steel rule die-cutting is performed on a clamshell press, GMN also utilizes vertical, cylinder, horizontal, roll-to-roll, and hydraulic punch presses to cut a broad array of materials such as polycarbonate, paper, foam, Lexan, and aluminum. The hardness of the material directly influences the maximum material thickness that the presses can accommodate.
Advantages of steel rule die-cutting
With the versatility to accommodate varying shapes, sizes, materials, and designs, steel rule die-cutting is undoubtedly one of the most popular die-cut fabrication methods to meet your unique needs. Steel rule dies allow up to 10,000 hits approximately, and therefore, can be used for medium to high production volumes. In addition to achieving tolerances as low as 0.01”, steel rule die-cutting offers you the flexibility to accomplish kiss cuts, custom-shaped die-outs, clean cuts, scoring lines, and perforations.
Limitations with steel rule die-cutting
One of the limitations with steel rule die-cutting is that the steel rule has a minimum bending radius of 0.03” which means that any designs with square corners or the ones that require the steel rule to bend less than 0.03” are not suited for this technique. Nonetheless, it is a highly preferred solution due to its cost-effectiveness when compared with chemical etch dies and Class A tools.
To see some of the clamshell presses at GMN in action, watch our video here.
Embossing, the process of raising logos or graphic images, is a great way to augment the visual impact of any component. The tactile feel achieved as a result of the raised design reinforces the aesthetic appeal of a product. Embossing is one of the most versatile metal decoration techniques employed by a wide array of industries.
While there are different ways to emboss a component, how do you ensure the utmost precision while embossing decorated parts? How can the varying tolerances of the decoration process accurately align to a mechanical embossing operation? The answer to all these questions lies in our video below that clearly demonstrates the advantages of adding an optical registration system to the embossing process.
To illustrate the registration challenge imposed by any decoration process on embossing, let’s delve deeper into the HySecurity nameplate seen in the video. During the screen printing process, when a squeegee travels across the metal sheet, the deposition tolerance between the images can vary as much as 0.005” per inch. As such, an image from the leading to the trailing edge of a 24” sheet can vary around 0.12” (0.005” x 24”). Conversely, the mechanical action of the embossing die does not exhibit this variation. So, when an operator feeds the metal sheet to the embossing machine, the tool cannot align accurately with the varying deposited images, sometimes creating an off-registered embossed part.
We can overcome this alignment challenge by adding an optical registration system to the embossing process and depositing a corresponding registration mark next to each design. In doing so, when the nameplate is being screen-printed, a registration mark is put down at the same time that correlates to the center of each artwork. At the embossing stage, the press uses an optical eye to locate the mark and make necessary adjustments to gain alignment between the printed graphic and the tool pitch, resulting in perfect embossing. Since the press automatically calibrates the location of every individual artwork and advances the sheet through the press, the process is ideal for parts that demand extremely tight registration. Resulting in extreme precision and accuracy, optical registration embossing provides a high degree of efficiency and consistency. The press overcomes tolerance variation that the actuator-fed emboss press falls short of.
The press can emboss a range of metals and alloys including stainless steel and aluminum. While the thickness of the material processed is directly related to the press tonnage of the machine, the embossing height depends on various factors such as the thickness, temper, and alloy of the metal. Since certain alloys have greater elongation characteristics, they can be embossed to a greater height as compared to the others. The press can emboss, deboss (recessed images), or perform both the processes simultaneously. It is well suited to emboss parts that are either screen, pad, or litho printed. Depending on the design intent, embossed parts can undergo secondary processes like forming, blanking, and die-cutting at a later stage. To see how the Vforce nameplate, featured in the video, went through diamond carving after it was embossed, watch our video here.
Over the last few decades, GMN has worked with several leading companies including Ford, Dell, Estée Lauder, and DW drums, to create clean and crisp embossed parts. To watch the embossing process, click on the video below.
When a leading auto supplier was designing the backlighting module for a new gear shift indicator (otherwise known as a PRNDL), they came to GMN to develop a custom light diffuser. The PRNDL would be featured in a line of premium vehicles, so the diffuser needed to ensure that the backlighting met strict standards for consistent brightness and uniform color in all lighting conditions.
GMN’s experts took to our state-of-the-art light lab to engineer a backlighting diffusion solution that met all of the project requirements. Leveraging GMN’s automotive experience, backlighting expertise, and printing capabilities, the diffuser successfully made its way onto PRNDLs in two separate vehicle models that can be found all across the world.
To learn how GMN successfully tackled a tough backlighting diffusion challenge, read our latest case study here.
Whether it’s etching, engraving, or cutting materials, laser technology plays an integral role in the fabrication and decoration of various components. But how do lasers exactly work? Which materials can a laser cut? What are the key advantages of utilizing lasers in the manufacturing industry? By demonstrating the working of a few laser cutters at GM Nameplate (GMN), our video will answer all the above questions.
How does laser technology work?
As seen in the video, a laser is mounted on an X-Y motion stage of the cutting machine. Installed perpendicular to the substrate, the laser moves across the surface to heat, melt, and vaporize the material. As opposed to a standard flashlight, the light released here is coherent, monochromatic, and directional. The core cutting characteristics, such as depth, speed, and power, are dictated by the wavelength and the frequency of the laser light.
Laser cutting machines at GMN
The laser cutters at GMN can be categorized into the following three types -
- Fiber laser – Creating light by banks of diodes, fiber laser channels and amplifies light through a fiber optic cable. The wavelength created by a fiber laser is ideal for marking and etching intricate patterns.
- CO2 laser – Utilizing CO2 as the amplifying medium, CO2 laser uses an electrical charge to excite the gas in a discharge tube to emit light. The frequency of this laser is ideal for cutting a broad range of substrates.
- Nitrogen laser – Similar to a CO2 laser, it uses nitrogen as the lasing medium to produce the cutting beam. At GMN, a nitrogen laser is employed for cutting aluminum and stainless steel.
To control the quality of the output, the laser cutters can also be accompanied by an assist gas such as nitrogen or air. The assist gas curtains the laser beam to swiftly vaporize the material after cutting, ensuring smooth and unblemished edges. Nitrogen gas assist is particularly suited for projects where upholding the aesthetics of the material is critical. By creating an inert field around the laser, nitrogen gas protects the substrate from unwanted flaming or burning. For any given application, it is the interplay of several factors such as design specifications, anticipated volumes, tolerance requirements, and cost restrictions, that determines the most appropriate laser type to utilize.
With machines ranging from 30W to 400W, GMN employs low-powered fiber lasers for etching and engraving. High-powered CO2 and nitrogen lasers are typically reserved for cutting thicker materials and metals. The wide array of laser machines allows GMN to cut numerous substrates including 3000 and 5000 series aluminum, magnetic (430) and non-magnetic (304 stainless steel) alloys, Lexan, acrylic, foam, polyester, polycarbonate, and vinyl. During laser cutting, calibrating the focus point of the laser beam is extremely crucial to achieve the utmost precision. Most machines at GMN are equipped with a computerized calibration system, where a focal arm travels closer to the material, gauges its thickness, and automatically adjusts the focal length of the laser.
Advantages of laser cutting
Versatile and easy to use, laser technology is extensively utilized at GMN for fabricating materials with extreme accuracy. When compared to other die-cutting techniques, the lead time for laser cutting is extremely short and last-minute changes to artwork can be quickly accomplished. Ideal for rapid prototyping and low-volume programs, laser technology is well suited for cutting complex shapes, creating registration holes, engraving intricate patterns, and etching serial numbers.
To see some of the laser cutters at GMN in action, watch our video below.
Autocar, one of America’s oldest large truck manufacturers, approached GM Nameplate (GMN) to design and produce a high-quality grille badge for their new line of DC-64 conventional trucks. The intent of the new grille badge was to feature Autocar’s historic bowtie logo, made to commemorate the 100th anniversary of its launch.
Given that the new line of trucks would be competing in the premium segment of utility vehicles, Autocar wanted an elegant, high-end badge with a three-dimensional look that would truly stand out. Since the DC-64 was a heavy-duty utility vehicle used at construction sites and for other outdoor applications, the badge also had to endure heavy impacts and abrasion.
Autocar’s previous badges were made of injection molded plastic with plated aluminum. While this met their visual requirements, the badge was prone to cracking, denting, or chipping when exposed to extreme weather or tough job conditions. Autocar wanted the new grille badge to be rugged and robust enough to maintain its premium look even in the most demanding environments.
After creating and testing several prototypes, GMN’s experts determined that the best approach would be to use a formed aluminum construction with an exterior capable roll coat. To achieve the desired look, the team began with a flat sheet of bright-finished aluminum. The Autocar letters and border were reversed out before the sheet was screen printed with jet-black ink. The decorated metal sheet was then formed and embossed, allowing the bright-finished aluminum to shine through and highlight the letters. In the end, a glossy, exterior-grade automotive topcoat was applied via roll-coating to protect the printed graphics from fading over time. It also imparted strength to the badge and helped realize the multi-dimensional look that Autocar was aiming for.
For additional durability and structural integrity, a molded plastic backplate with hand-applied foam adhesive was inserted behind the formed aluminum. This combination of unique processes resulted in a badge that was not only elegant, but also incredibly durable and resistant to environmental damage.
The commemorative grille badge has since been put into use on the entire line of DC-64 trucks and is even scheduled for use on other vehicles in Autocar’s fleet. This is just another example of GMN leveraging its diverse capabilities to meet the needs of our customers. To find out more about our automotive badging solutions, visit our website.