Have you ever wondered how aircraft interiors and Formula 1 cars are so stiff and light? The secret is sandwich panels. Sandwich panels are used whenever lightness and stiffness are required for a flat or irregular shape. The main theory behind sandwich panels is the concept of mass moment of inertia. Increasing the mass moment of inertia directly increases the stiffness. So how do you increase the mass moment of inertia while keeping weight down?
First, let's consider a solid carbon fiber plate. Thicker plates will be stiffer, but not just because there is more material. When layers are further from the center (commonly called the neutral axis) they contribute more stiffness. Consider two tubes of different diameter. The large diameter tube will be stiffer than the small diameter tube, even if the amount of materials in them is equal! This is because the larger diameter tube has more material further from the center.
An I-beam works using the same principal. The web of the I-beam (the skinny center section) holds the flanges (the end pieces) far from the center, making the beam much stiffer than a solid plate using the amount of material. (See Figure 1.)
So, we know a thick plate will be stiffer but we need something lightweight. That's when the sandwich comes in. When a plate bends, the outermost layers don't just add the most stiffness, they also take a majority of the load. Both faces will experience stress with one in compression and one in tension. Strangely enough, the center of a bending plate sees no stress at all! Therefore, if we know the center layers of a plate don't contribute much we can eliminate them and replace them with foam or honeycomb.
Replacing the center layers reduces overall stiffness a little bit, bringing us right back to the mass moment of inertia by effectively moving the load carrying materials (also referred t as the panel "skins") further from the neutral axis. If we make the core thicker we've increased the mass moment of inertia and increased the bending stiffness and strength. If we add more layers we can also increase the strength and stiffness since we add more materials far from the center, and we can distribute the load over more cross-section. Getting the thickness right results in a panel that is considerably lighter than an equivalent solid panel. Rock West Composites offers sandwich panels in a multitude of thicknesses and constructions to suit your needs. And as always, if we don't have it shoot us an email or give us a call and we CAN build it for you!
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Dear Valued Customers,
With the changing situation of the COVID-19 pandemic, we want to inform you of the current status of Rock West business operations. Rock West Composites is part of the Critical Infrastructure Sectors, and we continue to operate our facilities in San Diego and Salt Lake City in full capacity.
At the beginning of April, we suspended operations in our Tijuana, Baja California facility due to a national health emergency declared in Mexico, which was extended until the end of May. The facility is now back at full operational capacity. While recreational travel is currently prohibited in either direction across the US and Mexico border as a joint initiative to prevent the spread of COVID-19, business travel is allowed and our operations are not impacted.
We continue to monitor the situation daily and make decisions based on the guidelines set forth by the U.S. Government, the Centers for Disease Control and Prevention (CDC), and the World Health Organization. We recognize our role in protecting our nation’s infrastructure and protecting employee safety, and we take this role seriously. We are doing everything possible to honor commitments to our customers by completing programs on time.
Thank you for your attention and your business. Please stay safe
Composite products, like carbon fiber reinforced plastics (CFRPs), are laminate products structurally speaking. As such, a single crack in one laminate can grow without being visible to the naked eye – until the part fails catastrophically. Manufacturers vigorously test their products in an attempt to understand what leads to cracks and failures. Now they may have a more efficient way of doing so.
Thanks to research taking place at the University of Illinois at Urbana-Champaign, there appears to be a new digital method for testing composites. Scientists have shown they can create simulated computer models based on fiber information from a single sample to test multiple failure scenarios.
As things currently stand, testing composites is a mostly physical and mechanical exercise. Its inherent limits prevent scientists and engineers from testing every possible angle and external force that could cause cracks in a composite part. But with a computerized model, they can run a virtually unlimited number of tests to simulate whatever conditions they want.
The Physics of Carbon Fiber
When a customer buys carbon fiber fabric from us, the intention is to combine that fabric with an epoxy resin to create a CFRP part. When that part is finally finished, it will be a laminate part made up of thousands or tens of thousands of fibers oriented in different directions. Each layer of fibers is its own laminate in the finished product.
In any given part, there are multiple angles of intersection. Each angle represents another stress point that could be subject to failure. The researchers decided that the best way to establish baseline data for a simulated test is to look at areas of 90° intersection sandwiched between 0° plies.
From this understanding they developed a way to create a computer model consisting of hundreds of fibers intersecting at 90° with which they could simulate testing and compare the results against
Waste is something that must always be considered in the manufacturing environment. We are constantly thinking about it here at Rock West Composites. Our industry is especially sensitive to waste because composite materials disposed of in a landfill needlessly take up space without readily decomposing.
We even produce waste through prototyping. That waste is generated by the prototypes themselves, along with all of the process materials used to create the parts. If we can recycle the waste, that would be good. Some companies are doing just that. A case in point is a UK bicycle manufacturer that is now poised to begin recycling 100% of its prototype waste.
Making Carbon Fiber Rims
The company in question is Revel Bikes, makers of some pretty innovative wheel sets. They have worked with their composites partner over the years to create some of the best composite wheels and rims on the market. Yet all of their prototyping work has generated plenty of waste. Revel now thinks they have solved the waste problem.
First off, the company does not utilize carbon fiber materials made with traditional epoxy resins. We are not quite sure what they use, but their material is said to be environmentally friendly. They claim that their formula allows them to recycle 100% of their prototype waste for manufacturing other products.
So what do they do? Every piece of process waste is collected during the prototype stage. It is combined with the actual prototypes themselves and put through industrial choppers and shredders. The broken-down material is heated and shaped via compression molding. The end result is a carbon fiber tire lever.
Stronger Than Conventional Plastic
If you follow our blog posts, you understand that recycled carbon fiber is not as strong as virgin product. It cannot be used for certain types of applications for which reduced strength is not an option. Think airplane fuselage panels and hull panels for
FOR IMMEDIATE RELEASE
Rock West Composites Announces Quaranvent Design Competition Winner
Rock West Composites held the Quaranvent Design Competition during the late spring in response to the COVID-19 pandemic in hopes of providing a fun activity for those living under quarantine. The competition concluded at the end of May, and the winning design, a 15-foot lightweight inflatable backpack kayak by Craig Monroe, was announced last week.
San Diego, CA (PRWEB) July 4, 2020 – In early April, Rock West Composites (RWC) announced the Quaranvent Design Competition as a way of engaging with the public during the nearly nation-wide quarantine that happened in the late spring due to the COVID-19 pandemic. The period for entries closed at the end of May, and the prize options included combinations of cash, RWC product, and donations to organizations working on COVID-19 relief efforts. On June 25 the company announced the winner was Craig Monroe, who designed a 15ft kayak that was inflatable, incorporated RWC carbon fiber components, and could be easily transported in a backpack.
The judging criteria included the innovation and uniqueness of the idea, the usefulness of the design, the potential business case for the product, and the use of RWC materials and products. The inclusion of RWC materials was not required. Themes around the pandemic, flattening the curve, and social distancing were encouraged. The selection committee was excited about the variety of designs submitted but ultimately felt that the backpack kayak fit all the key points of the competition.
The winning entry keeps with the theme of social distancing and engaging in healthy activities. It uses a combination of inflatable parts and carbon fiber structural elements to make the kayak lightweight enough—at 12 pounds or less—for hiking. The innovative design collapses into a manageable backpack size, making it easier to transport and for the user to access remote areas by foot. The easy to assemble
Rapid prototyping is something we do here at Rock West Composites. Our team is uniquely qualified for rapid prototyping of composite parts thanks to our expert knowledge in material and process selection. We utilize the latest best practices and industry standards for prototyping to give our clients exactly what they are looking for. Our question for you is this: is rapid prototyping right for your project?
To be clear, we offer rapid prototyping as a means of giving our clients a fast and efficient way to bring drawings, specifications, or ideas to life. Through prototyping, we help clients get from the design stage to full production. Best of all, we can prototype both products and manufacturing processes.
The Basics of Rapid Prototyping
Also known more simply as RP, rapid prototyping was first developed in the 1980s. The idea behind it was to create a standard set of techniques that could be implemented quickly to fabricate models prior to manufacture and assembly. CAD design and 3D imaging have been an integral part of RP since the very beginning.
Rapid prototyping in the 21st century is still used primarily to help manufacturers get from design to full production. However, technologies have advanced to the point where the same RP principles can also be used for short run manufacturing. Such capabilities are important to customers in the composites arena.
The thing about composites is that they can be expensive to work with. As such, there are some companies that cannot justify using composites because full-scale production would not be financially viable. Rapid prototyping solves that problem. It allows for small numbers of parts to be created quickly, efficiently, and cost-effectively.
It Starts with a CAD Drawing
Just about every rapid prototyping project starts with a CAD drawing. Our team can work with your existing drawings or produce them for you. In either case, we offer quick turnaround in