When iterating a design that calls for plastic components, changing an injection mold requires significant capital and lead time that can impede innovation and slow the process. NXT Outdoors™ has overcome this challenge by harnessing Carbon’s SpeedCell™ system for their DrawLite™ product, a draw-activated sight light. Read this case study to learn how they successfully accelerated the design and production cycles of their product, integrating customer feedback faster without sacrificing cost or quality.
THE COST OF ITERATION
As innovators in outdoor goods, NXT Outdoors™ designers and engineers look to their own hobbies for inspiration and problem solving. They shared a frequent problem with their archery customers: a dead battery on illuminated bow sights, intended for assistance in aiming in low light conditions (Figure 1). Illuminating the sight required a toggle switch, which was easy to forget to toggle off. The archers had been blaming themselves for not toggling the switch, but why shouldn’t the sight turn itself off?
“Customer feedback is essential to improving products, and Carbon’s 3D Manufacturing system gave us unparalleled flexibility to iterate at will.”
Bryan RogersMechanical Engineer, NXT Outdoors
The designers prototyped a promising solution: a light attached to the sight, controlled by the bow being drawn. They tested it themselves, and committed to $79,000 in tooling. Customer feedback on the product was promising, but the installation time was about 15 minutes and the product could not be installed on all models of bows. If the ease of installation and time needed to install could be reduced, and the product could accommodate more bows, the designers could significantly improve the user experience. The next redesign of the tooling started at $5,000, and this iteration was unlikely to be the last change required. Like many consumer hardware vendors, NXT Outdoors™ needed a faster way to iterate their product design.
Figure 1: Left: The switch body and cap printed with the Carbon SpeedCell™ system. Right: The full DrawLite™ illuminated sight kit sold by NXT Outdoors™, including the switch housing, cable that activates the switch when the bow is drawn, and light to attach to the bow sight.
EXPLORATION THROUGH PROOF OF CONCEPT
Rapidly prototyping a new solution is an industry standard practice. Traditionally NXT Outdoors™ would still have to design an improved solution and modify their production tooling. Instead, NXT Outdoors™ was able to use Carbon’s solution.
Tony Schwartz, Lead Designer at NXT Outdoors™, and Bryan Rogers, Mechanical Engineer at NXT Outdoors, saw the SpeedCell™ system as a promising technology because of its isotropic properties, the freedom it gave them to iterate without tooling costs, and the quality of the material properties available. Because Carbon’s process renders isotropic parts, the same SpeedCell™ system was used for both product development and end production. This eliminates the usual process challenges that occur when prototyping product development (for example, on SLA or FDM printers) and production operations (for example, by injection molding, machining, or urethane casting) on independent equipment. They expected to learn more from new customer segments, so being able to change the product without changing the tooling was appealing. Lastly, Bryan identified Carbon’s Rigid Polyurethane (RPU) material as having mechanical, aesthetic, and cost properties for their application.
Figure 2: The body of the housing without the cap in place. The large cavity to the right holds the battery and associated electronics. The two smaller holes adjacent to it are threaded to hold the cap against the housing. The large hole to the left houses the draw-activated switch that completes the circuit and illuminates the sight.
Their next immediate goal was establishing a proof of concept. The cap and body of the housing were the primary plastic parts that had to be reworked, as all the parts to be installed attached to the body. They began by printing the original models, optimized for injection molding, on the Carbon printer and checking their mechanical performance under optimal conditions. After the first print, it was clear the RPU parts would be effective replacements in terms of mechanical quality and surface finish. Through the iteration process, NXT Outdoors™ redesigned the DrawLite™ sight to meet customers’ requests for quicker and easier installation, including accommodating more installation configurations. Additionally, they were able to print the internal threads, which were not possible to injection mold and traditionally would have demanded hand tapping afterwards.
Figure 3: The bottom of the printed body. Printed threads are visible on the side above the DrawLite™ logo, as well as the two symmetric holes on the top-facing surface.
Printing high-quality parts was just the beginning. The new approach with Carbon represented a fundamental shift in how the company could bring products to market. Because the prototype was the production part, once parts were qualified, there was no lead time needed to build more. By building parts and selling them in real time, NXT Outdoors™ could deliver products just-in-time and continually drive customer feedback into the design of the product, without the expense of modifying tooling for each iteration. (Read Carbon’s white paper on “Cost to manufacture with injection molding” to better understand all the costs associated with the traditional injection molding manufacturing process.)
COST, SPEED, OR QUALITY? PICK ALL THREE
NXT Outdoors™ completed six iterations after the initial part design (Figure 2). Each iteration included mechanical improvements, new insights from customer feedback, broader support for bow models, and optimizations for the Carbon printing process. The new design reduced the customer installation time from over 20 minutes to under 5 minutes. Later iterations expanded the bow models covered to effectively every type on the market, using a single kit. The kit is now compatible with left- and right-handed bow models, as well as four different thread sizes. The optimizations brought the print time from roughly 56 minutes per part to 38 minutes per part, a reduction of over 25%. With the Carbon Smart Part Washer™, the cleaning time was reduced from 35 minutes per batch to 6 minutes per batch, a reduction of over 80%.
NXT Outdoors™ has developed an innovative, patent-pending lighted sight that their users love. This was possible only because they embraced a philosophy of rapid prototyping, rapid production, and collecting and synthesizing customer feedback into the product—enabled by the Carbon SpeedCell™ system. This philosophy enabled a significantly improved user experience, production-ready parts, and a unit price comparable to injection molding.
Are you interested in gaining flexibility to produce consumer products that delight customers while reducing total costs and time-to-market? Contact Carbon to find out how 3D Manufacturing can help you hit this target.