In the following project, the theory of constraints was applied in order to implement a manufacture CAD-CAM system into the metal mechanic industry processes of polymers injection and blown of polymers. The research showed that the manufacture of the mold with the engraving took 223,17 hours. In the workflow for the manufacture of the mold, a restriction was found in the outsource service of CNC. It took 120 hours of the whole process and represent the 51,47 % the total time of tooling manufacturing. There is also a constraint found in the design time. It was 60 hours that corresponds to 26,88 % of the overall time. In order to reduce the time, a modern system of design in 3D and CAM was established to improve the model process of design and manufacture. A simulation by computational resource was applied to the plastic. The design was changed from 2D to 3D. The implementation was focused in the design. A software was installed to improve the speed of modeling methods with reliable information. In the manufacture of molds, a new CNC machine was acquired with three simultaneous axes to eliminate the outsource service. By acquiring the design system, the working time was diminished in 79% and regarding to the CNC process, the working time was improved in 88%. En el presente proyecto se aplica la teoría de restricciones para implementar un sistema de manufactura CAD-CAM en la industria del sector metalmecánico, en productos plásticos, mediante procesos de inyección y soplado de polímeros. En la investigación se determinó que la fabricación del molde para el producto a evaluar tuvo una duración de 223,17 horas y para el procesamiento de 240 kg de materia prima fue de 25 horas. En el flujo de operaciones para la fabricación del molde se encontró restricción en el servicio contratado de manufactura CNC con 120 horas de duración que corresponde al 51,47% del tiempo total de elaboración. La fase de diseño, tomó 60 horas que corresponde al 26,88% del tiempo total del proyecto. Para reducir los tiempos se mejoró el proceso de diseño y manufactura, mediante la implementación de un sistema moderno de diseño CAD y un proceso de fabricación CAM. Para elevar la restricción se cambia de un entorno 2D de trabajo a un sistema de diseño 3D, y se invirtió en una máquina con tecnología CNC. Con la implementación del sistema el tiempo se redujo en un 79% en el diseño, con respecto al proceso manufactura CNC el tiempo se redujo en un 88%.

This research explores fluid flow speed behavior in capillary channels using additive manufacturing, focusing on stereolithography (SLA). It aims to validate microchannels fabricated through SLA for desired fluid flow characteristics, particularly capillary-driven flow. The methodology involves designing, fabricating, and characterizing microchannels via SLA, with improvements such as an air-cleaning step facilitating the production of microchannels ranging from 300 to 1000 $\mathrm{\mu }\mathrm{m}$. Experimental validation assesses fluid flow speed behavior across channels of varying dimensions, evaluating the impact of channel geometry, surface roughness, and manufacturing parameters. The findings affirm the feasibility and efficacy of SLA in producing microchannels with consistent and predictable fluid flow behavior between 300 to 800 $\mathrm{\mu }\mathrm{m}$. This study contributes insights into microfluidic device fabrication techniques and enhances the understanding of fluid dynamics in capillary-driven systems. Overall, it underscores the potential of additive manufacturing, specifically SLA, in offering cost-effective and scalable solutions for microfluidic applications. The validated fluid flow speed behavior in capillary channels suggests new avenues for developing innovative microfluidic devices with improved performance and functionality, marking a significant advancement in the field.

This study presents a novel microfluidic mixer designed, fabricated, and characterized using additive manufacturing technology—stereolithography (SLA)—and harnessing capillarity principles achieved through microstructure patterning. Micromixers are integral components in optimizing mixing and reaction processes within microfluidic systems. The proposed microdevice employs a tank mixing method capable of blending two fluids. With a channel length of up to 6 mm, the process time is remarkably swift at 3 s, and the compact device measures 35 × 40 × 5 mm. The capillarity-driven working flow rates range from 1 μL/s to 37 μL/s, facilitated by channel dimensions varying between 400 μm and 850 μm. The total liquid volume within the device channels is 1652 mL (6176 μL including the supply tanks). The mix index, representing the homogeneity of the two fluids, is approximately 0.55 along the main channel. The manufacturing process, encompassing printing, isopropyl cleaning, and UV (ultraviolet) curing, is completed within 90 min. This microfluidic mixer showcases efficient mixing capabilities, rapid processing, and a compact design, marking it as a promising advancement in microfluidic technology. The new microfluidic mixer is a major step forward in microfluidic technology, providing a cost-effective and flexible solution for various uses. Its compatibility with SLA additive manufacturing allows for quick prototyping and design improvements, making it valuable for research and practical applications in chemistry, biology, and diagnostics. This study highlights the importance of combining advanced manufacturing techniques with basic fluid dynamics to create effective and easy-to-use microfluidic solutions.

The study investigated fluid dynamics in curved microchannels, exploring 3D printing parameters, channel geometry, and fluid properties, crucial for applications in medicine and energy. It highlighted the importance of microfluidics in handling small samples and enabling rapid analysis, stressing the need for precise measurement techniques to validate fluid velocity. Using 3D printing for microchannel design illustrated their utility, with microscopy aiding flow behavior comprehension. The research aimed to validate fluid velocity, covering technology analysis, microdevice design, fabrication, and measurement methodologies. It successfully fabricated microdevices confirming fluid movement via capillarity, revealing the relationship between channel radius and flow velocity. Distinct flow velocity patterns were observed, vital for design optimization. The study affirmed capillary flow as a spontaneous phenomenon, with fluid velocity variations along curved microchannels consistent with mass conservation principles in incompressible flows.