During circuit board manufacturing, custom fixtures are commonly utilized to ensure quality and to facilitate the operators’ work tasks. Conventionally, these fixtures are manufactured using subtractive manufacturing techniques such as milling. A product development project has been carried out in collaboration with Eskilstuna Elektronikpartner AB (EEPAB), a company that manufactures circuit boards through Surface Mount Technology (SMT) and Through-hole-Technology. The purpose of the study was to investigate possibilities with additive manufacturing (AM) to produce fixtures for use within the company’s circuit board production unit. The used methodology for product development was a modified variant of the generic product development process, focusing heavily on the concept development stages. Data collection was carried out through a literature study as well as meetings and discussions with employees at the case company. A specific circuit board was studied in the project. This circuit board contains through-hole-components that requires the use of fixtures to reliably meet the customer requirements fors oldering. The existing solution was to solder these components by hand, with the use of a custom hand soldering fixture. The components in question are six LEDs as well as a semiconductorpackage. The aim of the project was to provide the company with concept fixtures, designed for additive manufacturing, that enables selective soldering of these components. All prototypes developed in this project have been digital 3D CAD models. This approach was used since nocphysical copies of the circuit board would be available for study within the time frame of the project. Two research questions were designed to aid in reaching the purpose and aim of the study: Research question 1: How can fixtures for selective soldering be designed for additivemanufacturing? Research question 2: What factors should be considered when designing fixtures for selectivesoldering? The project resulted in two new digital fixture concepts, which in theory can replace the hand soldering fixture and enable selective soldering of the components. The results are presented as 3D visualizations along with prepared print files ready for 3D printing, in correct dimensions based on accurately measured Gerber data. The strength of the fixture concepts has been tested in computer simulations where the material was assumed to be isotropic. As a result, the effect of printer settings on the parts’ strength has not been tested. This report also contains recommendations for further research within the subject. Keywords: fixtures, design for additive manufacturing, 3D printing, circuit board manufacturing, selective soldering

Increasing application of Additive Manufacturing (AM) in industrial production demands product reimagination (assemblies, subsystems) from an AM standpoint. Simulation driven design tools play an important part in achieving this with design optimization subject to the capabilities of AM technologies. Therefore, the bus frames department (RBRF) in Scania CV AB, Södertälje wanted to examine the synergies between topology optimization and Design for AM (DfAM) in the context of this thesis. In this thesis, a methodology is developed to establish a DfAM framework involving topology optimization and is accompanied by a manufacturability analysis stage. A case study implementation of this developed methodology is performed for validation and further development. The case study replaces an existing load bearing cross member with a new structure optimized with respect to weight and manufacturing process. It resulted in a nearly self supporting AM friendly design with improved stiffness along with a 9.5% weight reduction, thereby proving the benefit of incorporating topology optimization and AM design fundamentals during the early design phase. / Ökad användning av Additive Manufacturing (AM) i industriell produktion kräver ett nytänkade av produkter (enheter, delsystem) ur AM-synvinkel. Simuleringsdrivna designverktyg spelar en viktig roll för att nå detta med designoptimering med hänsyn taget till AM-teknikens möjligheter. Därför ville bussramavdelningen (RBRF) på Scania CV AB, Södertälje undersöka synergierna mellan topologioptimering och Design för AM (DfAM) i detta examensarbete. I examensarbetet utvecklas en metodik för att skapa en DfAM-ramverk som involverar topologioptimering och åtföljs av ett tillverkningsanalyssteg. En fallstudieimplementering av denna utvecklade metodik utförs för validering och fortsatt utveckling. Fallstudien ersätter en befintlig lastbärande tvärbalk med en ny struktur optimerad med avseende på vikt och tillverkningsprocess. Det resulterade i en nästan självbärande AM-vänlig design med förbättrad styvhet tillsammans med en viktminskning på 9,5 %, vilket visar fördelen med att integrera topologioptimering och grundläggande AM-design tidigt i designfasen.