This time, we would like to introduce a high-difficulty cutting (machining) case that requires not only inclined internal machining on a long workpiece but also precise phase (angular) alignment between the gear section and the pocket section.
This product features a long, inclined internal geometry, which makes the machining process itself highly challenging. In addition, the machining time exceeds 20 hours, requiring stable accuracy to be maintained over an extended period. Even slight misalignment or step differences can affect the final finish, so special attention was required in selecting the machining method and setting the reference positions.
Our Approach
At Yumoto Vietnam:
① Only technicians with more than three years of machining experience are assigned to this process.
② Since misalignment can occur if the Z-axis height is not properly matched, simultaneous machining is performed.
③ If the material hardens, machining time increases, while excessive softness may cause deformation. Therefore, aluminum is used.
Through these three initiatives, we are able to achieve stable quality even in high-difficulty machining projects.
Difficulty of Pocket Machining
The most challenging part was the pocket machining process. Depending on the application and machining requirements, it was necessary to properly use Φ3 mm and Φ2 mm end mills. In addition, machining only with small-diameter tools would significantly increase the machining time, making it essential to optimize and refine the machining method.
Furthermore, there was a risk of step differences occurring on the machined surface during tool changes, which required careful and precise reference alignment.
Countermeasures
Since machining time would increase significantly if only small-diameter end mills were used, rough machining was first performed with a φ6 mm end mill. The process then proceeded step by step to φ3 mm and finally φ2 mm end mills for finishing.
In addition, the Z-axis height was re-aligned each time a tool change was made to prevent step differences on the machined surface and to stabilize machining accuracy.
Regarding the alignment of the protruding sections between the gear and the pocket area, the gear section was machined using 3-axis machining, followed by 4-axis machining for the pocket section. To ensure correct phase (angular) alignment between the two sections after 3-axis machining, the angular origin was re-established and reference positions were re-adjusted during 4-axis machining, achieving a high level of consistency.
In this way, by addressing multiple challenges such as long machining time, effective use of small-diameter tools, prevention of step differences during tool changes, and precise phase alignment, we were able to achieve stable machining quality through optimized machining methods and strict reference control.
Yumoto Vietnam will continue to examine the most suitable approaches for each high-difficulty machining case and strive to deliver manufacturing solutions that meet our customers’ needs.
Copyright ©2023 Yumoto Vietnam Co., Ltd.
