Designing a Gibson guitar is no ordinary task. The brand is synonymous with quality and legacy, which means they need to stay true to their roots, even while innovating. It involves a harmonious blend of art, engineering and a deep understanding of the materials involved.
Kara Tucker, a Product Development CAD Designer at Gibson, described the process of creating guitars using SOLIDWORKS. From the challenges of working with wood to the intricate reverse engineering process, Tucker sheds light on the meticulous craftsmanship behind each instrument.
Gibson is known for their legendary guitar shapes, but even with a steadfast history, there’s still engineering and design that needs to be done. (Image credit: SOLIDWORKS.)
Respecting the Wood
Tucker’s journey to Gibson began with her experience working with wood and plastic at an escape-game company. Unlike common materials that are utilized in more traditional engineering work, wood is ever-changing and encompasses a range of species that present different qualities both at the production level and over the life of a guitar.
“I would describe my design work with the game company as wooden based structures—cabinets, with hardware, springs and magnets, stuff that pops out at you. The structures need to last because they are interacted with daily, and it’s very immersive. I learned a lot while I was working there and really got a feel for working with different kinds of species of wood.”
Each assembly of a guitar incorporates various woods and other materials that tend to stretch and deform over time. While this can be a challenge when manufacturing, it’s more about designing for what will come eventually—preparing the design to play well off the shelf and still play well after decades of aging.
Tucker and the engineers at Gibson aim to have tight tolerances while respecting the unique properties of wood. That’s why the company imports woods, and dries them to an 8 percent moisture content, lower than the industry standard of 12 percent, to minimize imperfections and ensure high-quality products.
She emphasized the need to work with the inherent characteristics of wood rather than against them, combining the skills of a woodworking artist and an engineer. The mechanical properties and hardness ratings of different wood species must be thoroughly understood to create successful designs.
Preserving History and Reverse Engineering
The rich history behind Gibson guitars is an essential element to not only preserving past features but also carrying them forward as they engineer instruments. To properly design and replicate the instruments, she delves deep into the historical context of each model, understanding the engineering intentions and the production processes of the past.
This knowledge allows her to design with purpose, respecting the original intent while considering the current production limitations. Reverse engineering plays a crucial role in the process, involving the use of 3D scanning technology from Creaform and software such as VXelements to move from mesh to CAD. Tucker and her team capture intricate details and dimensions of existing guitar models, retrofitting them into the SOLIDWORKS CAD environment.
“The shapes of the Explorer; the SG shape; the Les Paul shape. All of that is kind of already set in stone for us. Usually what ends up happening is the product development team will want to copy a neck. We’ll take a 3D scanner and scan an artist’s neck and reverse engineer that using our mesh-to-CAD workflow. What we’re doing is trying to retrofit a very particular feel of a neck onto whatever our modern technology allows us to construct it.”
Neck profiles are a critical element in guitar design. Gibson guitars feature asymmetrical necks with unique profiles, ranging from rounded to slim taper designs. Legacy instruments that have adapted and changed over time are even more unique and vary greatly.
Gibson engineers use a mesh-to-CAD workflow to scan legacy instruments and get them into the SOLIDWORKS environment. (Image credit: SOLIDWORKS.)
Reverse engineering these necks requires meticulous attention to detail, using splines and asymmetrical geometry to replicate their contours accurately. Each model presents its own challenges and the design process demands a deep understanding of the hand operations and material removal during manufacturing.
When Tucker started at Gibson, many of the engineers were still working in 2D CAD. That means a major element of the reverse engineering process isn’t just replicating specific elements of artists’ guitars, but also documenting the shapes in 3D CAD. Creating a digital historical context for the different instruments is important and it allows the Gibson team to understand just how the instruments change over time.
Scanning and creating CAD models of legacy and artist instruments is important for reproducing unique products, and also for documenting. (Image credit: SOLIDWORKS.)
From CAD to Creation
Transitioning from the digital world of CAD to the physical creation of guitars requires planning—and more planning on the engineering side than you might expect. Tucker ensures that the CAD designs consider the manufacturing process, accounting for variations that occur during machining and assembly, as well as the hand-sanding and other manual work that is done to refine the final products.
Factors such as fingerboard dimensions and tensioning of truss rods must be carefully considered in order to achieve a playable instrument. The reverse engineering process often involves accounting for material removal of 50 to 70 thousandths of an inch to achieve the desired final product.
Tucker provided an example of the nuanced engineering that needs to occur when they are reverse engineering instruments for contemporary production.
“We had a carved top, and I took the joining fret information—where the neck joins the body—and that acts as a constraint. The bridge height and the bridge playability that you put on this assembly also acts as a constraint. From there, we have to play around with the design to make sure that the neck and body are joined in a preferred way. There might be a riser involved, or an existing riser needs to be more complex.” The tiny details can make or break a guitar’s design and playability.
Other times, the engineering work isn’t quite so constrained. For instance, they will sometimes have to develop full-on assemblies or rework various pieces of hardware. Tucker explained one project where they were developing a new tailpiece that would be more adjustable and springier.
“Sometimes, it’s almost like a Mr. Potato Head sort of situation and then in other cases, it’s brand-new stuff. It really varies based on what the end goal happens to be. Because I’m so detail oriented, my bosses have to remind me, ‘Kara, you’re not designing a rocket.’ Even though it’s just an instrument, there’s still so much value in keeping the nuanced details in consideration.”
Designing Gibson guitars is a testament to the intricate artistry and engineering prowess involved in crafting these iconic instruments. Tucker’s passion for her work shines through as she navigates the complexities of wood, reverse engineering and the preservation of historical designs. Even on a production line, each Gibson guitar is worked by hand and the design and engineering processes take that into account as they develop each instrument.