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.
When it comes to product development, testing the materials and technologies used in a design under different lighting conditions is a critical step in the development process. External lighting plays a crucial role in how a part looks and functions, so the component must meet project requirements in all intended settings.
Whether testing for display readability, color matching, backlighting diffusion, or anything else, GMN has a state-of-the-art Light Lab to precisely control lighting to allow accurate testing for several variables. But how exactly does GMN’s Light Lab accomplish this?
What’s inside GMN’s Light Lab?
GMN’s Light Lab is a large, dark room outfitted with different lighting and testing equipment. Keeping the room as dark as possible is critical to getting accurate lighting values, so the walls are painted jet black. Even the brightness of the monitors used with the equipment is cautiously controlled, as any additional light can cause readings to be off.
There are two main specialized lighting sources used for illumination and testing within GMN’s Light Lab –
- Specular contrast source - It contains a bright quartz lamp in a specially-coated housing. The housing reflects and diffuses the light from the lamp, allowing it to disseminate to mimic different indirect and ambient lighting conditions.
- Direct light source - It focuses a powerful beam of light directly onto the testing surface.
These two light sources are frequently used in conjunction with each other to replicate outdoor environments, where there would be both direct and diffused lighting.
Across from the light sources is a five-axis motion system that contains an orthogonal goniometer, which holds the device under test. The goniometer can achieve a complete ±90° vertical and horizontal viewing angle, accommodating almost any angle for testing. Custom fixtures designed for each part or device are attached to the goniometer to ensure that they’re held in place while the platform rotates. Optical testing instruments, such as cameras and a spectroradiometer, sit next to the light sources on a separate moveable fixture.
While we’ve spoken previously about our vast display testing capabilities, GMN’s Light Lab is also used for overcoming tough backlighting and color matching challenges. For highly regulated industries such as the medical or aerospace field, overlays, labels, and placards may need to meet precise color specifications in specific lighting scenarios. Likewise, keypads or displays with backlighting may need to meet color or luminance specifications while in use. Our Light Lab is equipped with multiple cameras and a spectroradiometer to verify color values, luminance values, and color matching.
GMN can help design custom testing programs to your specifications, saving valuable time in the development process while maintaining product quality and consistency. To learn more about our in-house testing capabilities or discuss your project needs, visit our website or schedule a consultation with our experts.
Projected capacitive (PCAP) touch technology has become a popular user interface option for many industries in recent years. Not only do they offer a sleek, intuitive user experience, but the possibilities for backlighting a capacitive touch circuit are nearly endless.
While capacitive touch technology incorporates well with a variety of backlighting options, the design of the circuit is an important consideration. If designed improperly, the switches can potentially impede parts of the lighting, resulting in an uneven or inconsistent look.
How can capacitive touch circuits affect backlighting?
Capacitive circuits work by projecting a capacitive field and measuring any changes to the capacitance. This capacitive field is most commonly generated using circuits printed with conductive ink. Standard conductive inks, such as silver, carbon, or dielectric ink, can pose challenges when printing backlit PCAP circuits. Due to the opacity of the inks, they can block backlighting and result in uneven lighting or shadowing on the switch.
Fortunately, there are several methods to ensure that backlit capacitive touch circuits illuminate uniformly every time. Below, we’ll be going over the three most common techniques we use at GMN to ensure consistent backlighting.
Methods for backlighting capacitive switches:
One of the simplest ways to backlight a PCAP switch is by selectively printing around any backlit areas or iconography. When using an inexpensive carbon or other opaque ink, icons or symbols can be left unprinted within the design. As the backlighting rises through the switch, the light only comes through the unprinted area, resulting in a user-intuitive illuminated icon.
However, there are a few requirements to employ this backlighting technique. First, the switch area needs to be large enough for iconography to be left unprinted. In addition, there needs to be enough conductive ink surrounding the unprinted area to complete the circuit and result in an effective switch. This method is ideal for large or geometrically simple switch designs.
Backlighting through clear conductive ink
For smaller or more complex switch designs, a solution that has been recently gaining popularity is using clear, polymer-based conductive inks (such as PEDOT ink). These inks run from translucent to nearly transparent and allow the circuit to be lit from directly underneath. Unlike a switch that uses opaque ink that potentially blocks lighting, clear ink conducts electricity the same way but allows light to pass through the circuit unobstructed. While transparent inks are more expensive than opaque alternatives, they can be applied the same way through screen printing.
Another advantage of using these inks is that the translucency can be altered based on the type of ink and thickness of the deposition. Less transparent inks also act as a lighting diffuser, thereby eliminating hotspots.
Altering the capacitive touch stack-up
Another solution is to engineer the stack-up so that the backlighting source sits above the capacitive circuit. While most capacitive touch circuits are backlit from underneath, rearranging the backlighting source (typically light-guide film or fiber optic bundles) to sit above the PCAP switches can ensure that the circuits do not impede any lighting.
While this is an effective method, the sensitivity of the PCAP switch needs to be tuned to accurately register inputs through the backlighting layer. Lighting hotspots are also a potential concern as the backlighting sits directly underneath the overlay, but this can be easily solved by adding a diffuser.
The above solutions are often mixed and matched depending on the design to ensure that each part of the interface is consistently lit. GMN offers a host of different backlighting solutions for nearly any project. To discuss your specific backlighting needs, schedule a consultation with our experts.
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.
In our previous blog, we talked about the most common types of thermoplastics used in injection molding and how they compare against each other. Today, we’ll be going over improving the characteristics of resins with plastic additives.
What are plastic additives?
Plastic additives are compounds added during the formulation of the resin to improve the mechanical properties of plastic. Whether you are looking to impart heat resistance, improve structural integrity, increase lubricity, or enhance other characteristics, plastic additives can be a great way to heighten current attributes or add new properties to preexisting plastic. At GMN, we have access to a large variety of plastics additives to solve almost any production challenge.
What are the different types of plastic additives?
Glass and carbon
Carbon and glass are commonly used material additives that add structural integrity, toughness, and rigidity to a thermoplastic. They are helpful when a part needs to support weight or endure a harsh environment for extensive periods. While the amount of glass or carbon added to a resin can be highly specified, given how abrasive this additive is, adding too much can prematurely wear down tooling.
As the name suggests, fire retardants are compounds added to plastic resins that help inhibit burning. They are particularly useful for materials such as polycarbonate, which may struggle with flammability restrictions. There are different kinds of fire-retardant additives, and many plastics are available with varying amounts of added fire retardant depending on project requirements.
Plastic components are often subject to damage when exposed to direct sunlight or other ultraviolet light sources. Extended exposure can diminish the mechanical performance and alter the color of a plastic part. Adding UV stabilizers to the plastic can protect components from degradation and discoloration resulting from subjection to ultraviolet rays.
Colorants are plastic additives that alter the color of plastic. Unlike other additives which are added to plastic during formulation, colorants can be mixed in during injection molding to help achieve custom colors. Whether a part needs to match a specific color for branding purposes or simply needs to add contrast to a design, colorants allow most thermoplastics to achieve nearly infinite color possibilities.
Depending on how a component is designed, it can sometimes be difficult to remove it from the tool. Often, this issue doesn’t arise until later stages in the manufacturing process. Instead of completely redesigning the mold, it’s often simpler to use plastic that contains release agent additives. These additives add lubricity to the component, so it can be easily ejected from the tooling.
Teflon is an additive commonly used for high wear and tear applications or parts that face a lot of friction throughout their lifespan. It can help increase the lubricity of plastic, thereby reducing friction when it makes contact with other components and ultimately improving durability.
While the above are the most common additives at GMN, it’s far from an exhaustive list. Additives are frequently mixed and matched with different plastics to create custom solutions for tough injection molding challenges. To discuss your specific plastic component needs, schedule a consultation with our experts.
When it comes to designing a new plastic component, it’s important to realize that no material is a one-size-fits-all solution. Characteristics such as cost, temperature resistance, manufacturability, impact resistance, and structural integrity can vary widely between resins used for injection molding.
Considering all the different polymers and blends available, how do you decide which one is right for your next project? Below, we’ll be highlighting the key features of the most commonly used thermoplastics here at GMN.
What are the most common types of plastic for injection molding?
Commodity plastics are inexpensive plastics typically used for high-volume applications. The two most popular commodity plastics at GMN are polyethylene (PE) and polypropylene (PP). Both are very versatile resins that are buoyant, hydrophobic, and chemically resistant, making them ideal for a variety of plastic products.
While PE and PP both have decent impact resistance, they aren’t as durable as other plastic materials and are susceptible to damage from ultra-violet light exposure. The two resins are favored for cost-effective and lightweight items, such as reusable water bottles, toys, and disposable plastic packaging.
Acrylonitrile butadiene styrene:
Acrylonitrile butadiene styrene (ABS) is one of the most commonly used materials at GMN Plastics. A naturally high-sheen resin, ABS has high levels of impact resistance and strength, making it an excellent choice for bezels and housing.
ABS is also available with several additives (such as glass, colorants, or Teflon) to enhance its inherent mechanical properties. It also tends to be relatively inexpensive, making it ideal for high-volume applications that may require more durability than a commodity plastic.
Polycarbonate (PC) is ideal for a multitude of projects due to its versatility. Polycarbonate has good electrical insulation, impact resistance, heat resistance, and fire-retardance. Polycarbonate is also naturally transparent, which means it’s a good choice when clarity is important as it can easily be matched to different colors with the addition of colorants.
While it isn’t quite as inexpensive as commodity plastics like PE and PP, polycarbonate tends to be reasonably priced. Many different grades of polycarbonate are available with varying levels of additives for additional strength, making it ideal for a wide variety of projects.
Engineering polymers are a family of highly engineered resins that have exceptional mechanical properties. While the exact characteristics differ, they generally have high impact resistance, stiffness, chemical resistivity, flame retardance, and heat resistance.
Often used in highly regulated industries such as the aerospace and medical fields, the most common engineering polymers used at GMN are Ultem (polyetherimide - PEI) and Radel (polyphenylsulfone - PPSU). Polyetheretherketone (PEEK) and other materials as specified. While each of these offers a host of different benefits for plastic injection molding, given how highly specialized they are, they can be expensive and difficult to obtain.
GMN Plastics has decades of experience in not only creating custom plastic components for a wide array of projects but also incorporating them into complete assemblies to provide a holistic solution. To learn more about our injection molding capabilities, visit our website or schedule a consultation with our experts.
At GMN, the health and safety of our employees and partners is our top priority. To help protect everyone against the spread of the novel coronavirus, GMN held its second on-site COVID-19 vaccine clinic yesterday. Taking place at the Seattle, WA plant, the clinic was open to all GMN employees and their family members.
Since the COVID-19 vaccines became available to the general public in early 2021, finding individual vaccination appointments proved to be time-consuming and challenging for many. To make the process simpler, GMN Seattle’s HR department worked with local medical partners to set up an in-person vaccine clinic at the plant. The clinic gave employees and their families a convenient way to obtain their vaccines without having to spend time and resources finding and traveling to appointments.
GMN recognizes that vaccination is one of the most important tools we have to control the spread of the pandemic and strongly encourages all employees to get vaccinated. At other GMN divisions where on-site clinics aren’t feasible, our HR staff is continuously helping employees find and schedule appointments with local pharmacies and healthcare providers. Today, more than 61% of our employees across all US divisions are fully vaccinated, and many more have already received their first dose of the vaccine.
We also continue to abide by the other preventative measures instated across all GMN divisions, including social distancing markers, daily temperature checks, frequent disinfection of common areas, mandatory mask requirements, sanitizing stations, and more.
GMN is proud to help protect employees and our community against COVID-19. To learn more about our safety protocols and visitation policy during the pandemic, read the latest developments here.
We are excited to announce that GM Nameplate (GMN) was recently recognized as a Bronze Tier Supplier for exceptional performance and contributions to supply chain success in 2020 for BAE Systems, Inc.’s Electronic Systems sector. GM Nameplate was honored at a virtual ceremony and was selected from the pool of suppliers that worked with BAE Systems in 2020.
“At GMN Aerospace, we operate in an environment where meeting increased efficiencies and customer’s cost objectives are front and center,” said Mary Corrales, New Product Manager at GMN Aerospace. “We celebrate this achievement as a team as we continue to focus on always getter better and taking care of our customers.”
Jeff Lee, New Product Manager at GMN Aerospace added, “To receive this recognition is the result of our entire organization’s commitment to excellence and to our strong collaboration with BAE Systems. On behalf of all of us at GM Nameplate, thank you!”
BAE Systems’ Partner 2 Win program is designed to achieve operational excellence and eliminate defects in its supply chain by raising the bar of performance expectations to meet the demand of current and future customers. As part of the program, BAE Systems meets regularly with its suppliers to transfer best practices to ensure that the components and materials that compose BAE Systems products meet the highest quality standards.
“We are proud of the partnership we have with companies like GM Nameplate that delivered the highest quality products on-time, despite the challenges presented by a global pandemic,” said Kim Cadorette, vice president of operations for BAE Systems’ Electronic Systems sector. “We recognize that our suppliers are critical to our company’s success. We are grateful for this year’s outstanding effort, and we look forward to future collaborations.”
GMN is proud to be recognized by BAE for our continued support of their manufacturing needs. For more information on this recognition, read our full press release here.
This blog is the second in our series on functional inks. In the previous blog, we touched upon the various conductive inks used at GM Nameplate (GMN). In this blog, we will explore the different types and applications of non-conductive inks.
Non-conductive inks at GMN
Non-conductive inks, as the name indicates, do not conduct electricity, but are employed in vital functional products and decorative applications including sensors, membrane switches, graphic overlays, and labels. The non-conductive inks used at GMN include:
As a custom manufacturer, GMN utilizes graphic inks in a wide range of its components and brand identity products such as nameplates, labels, decorative signs, decals, placards, elastomer keypads, and graphic overlays. The various types of graphic inks that GMN offers include solvent-based inks, water-based inks, UV curable inks, epoxy inks, and air-dry inks. The selection of the appropriate ink for any given application is dictated by a multitude of factors like surface energy and surface tension of the substrate, environmental conditions, and cost. GMN regularly employs screen printing, digital printing, lithographic printing, UV inkjet printing, and UV flexographic printing for the printing of graphic inks. With decades of experience, GMN can create an exact color match or provide a color that matches the Pantone matching system.
Dielectric inks are electrically insulating inks that work in tandem with conductive inks by protecting them. In a multi-layer construction of circuitry, dielectric inks prevent the various layers of conductive ink from interacting with each other. By creating insulating barriers, they avert electrical shorting and silver migration. Since most dielectric inks are ultraviolet (UV) curable, they can be used on a broad spectrum of rigid and flexible substrates including bare or print-treated polyester, polycarbonate, and glass. They offer strong adhesion properties, superior flexibility, resistance to moisture, and abrasion and are minimally affected by folds and bends. Dielectric inks are commonly used in membrane switches, Radio Frequency Identification (RFID) tags, antennas, and electrodes.
While dielectric and graphic inks significantly dominate the realm of non-conductive inks at GMN, the use of specialty inks are gradually crawling up in the product development phase. The unique characteristic of specialty inks is finding new functional and decorative applications. The most common types of specialty inks seen today are:
a) Thermochromic inks: These are temperature-sensitive inks that change color when the ambient temperature increases beyond a pre-designated value. They come in many colors like shades of neon, blue, purple, etc. Common applications include labels, print advertising, fabrics, biomarkers, and sensors.
b) Photochromic inks: These inks temporarily change color when exposed to UV light. Similar to thermochromic inks, these photochromic inks also come in several colors. They can be seen in light-sensitive eyewear solutions, body patches to detect exposure to sunlight, and clothing.
c) Hydrochromic inks: These inks change color when they interact with or get immersed in water. Typical applications include packaging solutions, decorative umbrellas, and clothing.
GMN relies on industry-leading ink compounders to formulate custom inks for its varied customers. Our long-standing relationships with ink compounders enable GMN to mitigate price volatility and improve efficiency by reducing production lead times. It also allows GMN to meet diverse manufacturing needs and remain agile during the product development process. While each application calls for a specific ink and printing process, GMN works with each customer from beginning to end to determine project requirements and provide effective solutions. To discuss your upcoming projects, schedule a free consultation with GMN experts today!
Functional inks are a cost-effective method to manufacture printed and flexible circuits. While the traditional technologies of etched copper flex circuits and printed circuit boards (PCBs) are still prevalent, functional inks have the advantage of being an economical alternative when it comes to printing on flexible substrates and mass-scale production of circuits. In this two-part blog series, we will broadly touch upon the essentials of functional inks employed by GMN in its wide-ranging manufacturing services.
Depending on the ink type and final product application, functional inks can be applied on a wide gamut of both rigid and flexible substrates using various printing techniques including screen printing (sheet-fed and roll-fed), aerosol jet printing, and gravure printing. Functional inks are undeniably more environment-friendly than traditional technologies. While the subtractive process of etching copper on PCBs requires acid baths, the additive process of using functional inks does not produce any waste streams or involve any hazardous chemicals. Functional inks can be classified into two categories: conductive inks and non-conductive inks. In this blog, we will broadly explore the various conductive inks used in GMN, their properties, and their applications.
Conductive inks at GMN
Conductive inks, as the name suggests, are inks that conduct electricity. They are commonly seen in capacitive and membrane switches, Radio Frequency Identification (RFID) tags, touch screens, biomedical and electrochemical sensors, Positive Temperature Coefficient (PTC) heaters, electromagnetic interference/radio frequency interference (EMI/RFI) shielding, and more. Recent developments in stretchable conductive inks are also leading the evolution of wearable electronics.
For any given application, the two C’s that primarily govern the conductive ink selection process are cost and conductivity. Some other key factors that govern decisions include substrate compatibility, the ink’s molecular structure, final product application, and power efficiency requirements. Some of the conductive inks employed by GMN include:
Silver and silver chloride inks
Silver inks offer superior conductivity and low resistance. They are compatible with a broad range of substrates including polyester, polycarbonate, glass, and vinyl, and are resistant to abrasion, folds, and creases. Their high adhesion, high flexibility, and ease of printability have made them the ideal choice in medical electrodes and membrane circuits.
Carbon inks offer higher resistance, lower conductivity, and superior durability as compared to silver inks. They protect silver inks from silver migration, shield circuits from shorting, and are cheaper than silver inks. They also offer similar benefits as silver inks in terms of adhesion properties, ease of printability, and substrate compatibility. Carbon inks are often blended with silver inks to achieve the desired balance between resistivity, conductivity, and cost. Typical applications at GMN include cost-effective capacitive touch switches.
Gold and platinum inks
Given the huge cost hurdles associated with noble metals like gold and platinum, these inks are usually produced and utilized in very small quantities. GMN occasionally employs them in the product development stage or in applications where performance benefits outweigh the cost barrier. For example, gold is used in applications where high oxidation resistance is crucial and platinum is seen in applications that demand high conductivity.
Other metal-based inks
Copper ink can be used as a cheaper alternative to silver inks, given its high conductivity, but its low stability often poses limitations on its use. While nickel offers high durability, it is more expensive than carbon inks.
To learn about non-conductive functional inks, stay tuned for our next blog.