To meet a 30-day deadline for designing, molding, decorating and shipping more than 150 impact-resistant carriers for POWERADE® drink bottles to the 2014 FIFA World Cup Brazil™, the design and build teams at American Precision Prototyping (APP) turned to a combination of 3D printing / additive manufacturing and materials.
According to Jason Dickman, president of American Precision Prototyping, LLC, Tulsa, Oklahoma, “Time constraints on prototyping projects are often a challenge. This latest project for The Coca-Cola Company called for round-the-clock teamwork which is now being rewarded as we see the drink carriers that we produced on sports broadcasts from the World Cup games.”
Design and 3D CAD
At the start of this project, the team at APP was supplied with two earlier POWERADE® carrier designs, from the 2012 UEFA European Championship and the U.S. tournament. The client’s goal for the new World Cup carrier was to combine the ergonomics of the U.S. carrier’s design with the overall size and shape of the UEFA carrier. In addition, POWERADE® requested that the part be produced in two identical halves that would be joined to make a completed beverage holder. This meant APP had to start by developing a new concept from scratch.
The design team began to construct 3D CAD models in SolidWorks. Because of the four-week lead time, this project phase, including obtaining concept approval from POWERADE®, was allotted a week of the production schedule. APP quickly came up with a design that met the client’s standards for size, ergonomics, and construction. The six-bottle carrier concept, as requested, was built using two part halves that could easily be snapped and screwed together to make one sturdy holder.
The next step was to construct a half-scale model of the carrier on APP’s 3D Systems’ iPro™8000 stereolithograpy (SLA) equipment. Accura® Xtreme SL resin was used to build the model as a proof-of-concept as well as for general fit checks in the design. The SLA process provided APP with a mix of speed and accuracy, generating a master that held tolerances to approximately 0.005 in.
Marketing executives from The Coca-Cola Company reviewed the half-scale model and made minor changes that were input directly into the 3D CAD file. Then, full-scale SLA parts were built for final fit check and for use as master patterns to pour silicone rubber molds.
Moldmaking and Casting
Typically, plastic parts are injection molded in precision-machined metal tooling. The process for building the molds is expensive and time-consuming, making it impractical for short production runs.
APP’s build team, therefore, used RTV silicone molds to create the carrier parts. The molds provided for fast, easy pouring over SLA patterns and offered excellent dimensional accuracy and reproduction of detail. In addition, because silicone molds are flexible, they facilitated demolding of undercuts that were part of the POWERADE® carrier design.
To prepare for building the molds, SLA resin masters were sanded and finished to produce the desired injection molding-like surface texture. This process ensured the casting of end-parts that had the look and feel of mass-produced products. Next, six silicone molds were poured over the SLA patterns to enable APP builders to cast and cure the 300 part halves required to produce 150 beverage carriers under the project’s tight time constraints.
For part casting, APP used Innovative Polymers’ InnoTuf® TP-4050 Impact-Resistant Polyurethane. The rigid material simulates the feel of injection-molded ABS thermoplastic. It has a Shore hardness of 80D, notched Izod impact strength of 2.0 ft-lb/in, flexural strength of 11,000 psi, and heat deflection temperature of 158°F (70°C). The material was easy to process and produced the performance properties needed to mold durable bottle carriers that could withstand shipping to Brazil and use by World Cup teams during the month-long tournament.
Art and Assembly
With about two weeks remaining before the tournament, APP began a round-the-clock finishing process. Only minimal surface cleaning and sanding of parts was required to remove vents, gates and flash because of the outstanding accuracy of the SLA patterns. Next, part halves were snapped in place and screwed together and pre-designed vinyl decals displaying the POWERADE® brand name and a dedicated 2014 World Cup hashtag were applied. Finally, carriers were packaged and shipped to meet project deadlines.
Dickman concludes, “Our dedicated team produced and finished 40 to 50 castings each day followed by labor-intensive positioning of decals to ensure outstanding quality and appearance. We are proud to have met the challenge of the POWERADE® project using our expertise and the latest in equipment, processes and materials.”
American Precision Prototyping, LLC