Case analysis of metal investment casting + CNC machining + polishing parts

We have just completed the production of a product. The structure of this product seems to be not difficult, but it is still difficult to produce it according to the customer's requirements. So, I would like to share this product with you.

As shown in the figure below, the main body of this product is an investment castings, but because the cylinders at both ends are relatively long, it is easy to deform during the investment casting production process. In addition, the two sections of the cylinders have assembly requirements, especially the coaxiality requirements of the two cylinders. Direct investment casting cannot meet the requirements, which requires secondary processing of the investment casting, so we need CNC turning to process the cylinders at both ends to meet the assembly accuracy requirements. This processing process needs to consider the coaxiality requirements and the problem of casting deformation. In this process, we need to customize the fixture and go through some subsequent processes, which are not listed here one by one. In fact, the most difficult part of this product is that the customer requires a mirror effect on the center of the product. Since most of the mirror surface is on the inner hole, it is very troublesome to polish it. It cannot be polished by machine, so it can only be polished by hand. In addition, the innermost hole is relatively small, and it is difficult for the polishing tool to move well, which greatly increases the difficulty of polishing. As shown in the red arrow in the figure below. Later, after our research and finding methods, we made a perfect product and delivered it to the customer.