# Feasibility Study of Integrated Precision Abrasive Machining of Shaped Surfaces
## 2 Materials and Methods
### Manufacture of the Dual-Tool Grinding Head  
After the head was designed, the manufacturing of the head proceeded. All non-standard parts of the head were made using a HAAS ST-10 turning lathe (HAAS Automation, Oxnard, CA, USA), a HAAS VF-2 milling center (HAAS Automation, Oxnard, CA, USA) and a conventional chiseling machine. To make all elements of the dual-tool grinding head, necessary processes were used, such as the following:  
* the process of turning the inner body of the head on a HAAS ST10 turning center;  
Figure 4: The 3D digital model of a dual-tool grinding head: (**a**) in the coarse grinding setting; (**b**) in the finishing grinding setting. Figure 3: The 3D digital model of a dual-tool grinding head: (**a**) external body view; (**b**) internal body view. the process of milling the outer body of the head on a HAAS VF2 milling center;
* the process of milling the inner body of the head on a HAAS VF2 milling center;
* the process of milling the M19\(\times\)1 mounting adapter on a HAAS VF2 milling center;
* the process of milling the pneumatic cylinder holder on the HAAS VF2 milling center;
* the process of chiseling the outer body of the head on a conventional chiseling machine made at the Tarnobrzeg Machine Tool Factory, model PABP-63. Figure 5c shows all the fabricated components of the prototype dual-tool grinding head and the fully assembled grinding head. The coarse grinding process using the head used a custom-made ceramic grinding wheel made at ANDRE ABRASIVE ARTICLES limited liability company, limited partnership (Figure 5a). This grinding wheel measured 110 mm by 24 mm and has a 55 mm diameter bore. In addition, 4 M8 threaded inserts were designed for mounting it in the grinding head. On the other hand, the finishing grinding process used a prone grinding wheel from 3M Poland limited liability company, which had a diameter of 50 mm with a roloc mounting system and Trizact(r) grains [33] (Figure 5b). The characteristics of the presented grinding wheels are presented in Table 1.  
Figure 5: (a) ceramic grinding wheel from ANDRE, type 3611-110\(\times\)24\(\times\)55-99A60K9V with four M8 threaded inserts; (b) a prone grinding wheel with Trizact® grains; (c) listing the components of dual-tool grinding head; (d) dual-tool grinding head mounted on the test bench. The next step was to prepare a pneumatic system to control the position of the dual-tool grinding head. For this, three pneumatic actuators with fork joints, high-speed bearings and rollers, two power strips supplying air to the actuators and a controller regulating the position of the pneumatic actuators were used. The test stand of the completed pneumatic system and the dual-tool grinding head were then assembled, as shown in Figure 5d. Figure 6a,b shows a view of the head with the actuators extended in the coarse grinding position, and Figure 6c,d shows the head with the actuators in the finishing grinding position. After the head body was prepared, the head was fully armed, i.e., the grinding wheels and the double head were installed. Views of the armed head in both positions are presented in Figure 6e,f. In the next step, the ceramic grinding wheel needed to be shaped. To this end, using Autodek Inventor Professional 2023 with CAM Ultimate 2023 software (Mill Valley, CA, USA), a program was developed that controlled the machine tool to shape the grinding wheel at a 15\({}^{\circ}\) angle using a diamond dresser. The result is presented in Figure 7. Figure 8 shows the fully prepared two-tool head along with the coolant feed linking directly to the grinding zone.