## 3 Materials and Methods
### Discussions  
While the designed device's dimensional and angular accuracy was rigorously validated through metrological inspection, providing sufficient evidence for its intended application in cutting tool and cutting regime studies, a detailed Finite Element Method (FEM) analysis of the fixture's vibration and stiffness characteristics was not within the primary scope of this initial research. The current study focused on demonstrating a practical and economical solution for enabling barrel milling on 3-axis CNC machines by ensuring precise workpiece orientation and rigid clamping.  
This research successfully aimed to design and validate a specialized device for enabling machining of inclined planes with barrel tools on a 3-axis CNC machine. The specific objectives included novel design, ensuring adaptability, and validating the device's performance. The results obtained from the verification, which demonstrated minimal dimensional deviations and high angular accuracy, confirm the achievement of the proposed objectives and highlight the device's innovative capability to precisely orient the semi-finished product--an essential aspect for the efficient use of barrel tools on a 3-axis CNC machine, which was previously a significant challenge.  
Existing solutions for machining with barrel tools frequently involve the exclusive use of 5-axis CNC machines, which can limit accessibility and significantly increase costs. This research presents a novel and viable alternative for situations where only 3-axis machines are available. The designed device ensures precise positioning of the semi-finished product, effectively compensating for the limitations imposed by 3-axis machines and enabling accurate results in machining with barrel tools, a capability not typically associated with these simpler platforms. The advantages of the device include adaptability to different programming angles, rigid clamping of the semi-finished product, and the integration of probing surfaces to facilitate the definition of the coordinate system. Figure 21 illustrates the jaw fixed in the vice, with and without the semi-finished product.  
The research presents certain limitations, such as the dependence on a specific type of machine tool and the necessity of using a specific device for each programming angle. To overcome these limitations, future research directions could include  
* Automating the changing of locating elements for different programming angles, which would increase the flexibility and efficiency of the device.
* Designing a universal device, adaptable to a wider range of programming angles without requiring component changes, which would reduce complexity and costs.
* Integrating sensors for monitoring cutting forces and optimizing machining parameters, which would allow for more precise control of the machining process and an improvement in surface quality.
* Extending the research to include machining tests with different materials and barrel tools, to evaluate the device's performance under various conditions and identify optimal machining parameters.
* Performing advanced simulations, such as Finite Element Method (FEM) analysis, to thoroughly evaluate the fixture's vibration and stiffness characteristics under various cutting conditions, thereby enabling further structural optimization.