Milling is often considered a more suitable option than tapping when machining highly adhesive materials, due to the impact of material properties on the tool during processing and the control of final thread quality.
Reduce tool sticking:
During the tapping process, due to the continuous contact between the spiral tool and the material, adhesive material tends to accumulate along the tool’s spiral groove, leading to tool clogging and reduced thread quality. In contrast, the intermittent contact of the milling cutter during the cutting process can effectively reduce the accumulation and adhesion of material, because there is an opportunity to discharge the chips after each cut.
Improve chip control:
Milling teeth allows for better chip control and evacuation, especially when using appropriate cutting parameters and toolpath strategies. Effective chip evacuation is important to prevent chips from re-adhering to the workpiece surface or clogging the tool, which is especially critical when machining sticky materials.
Provides better cooling and lubrication:
During tooth milling, it is easier to apply coolant or lubricant directly to the tool and the machined surface, which helps to lower the temperature in the cutting zone and reduce the adhesion of the material to the tool. In tapping, especially when processing internal threads, the use of coolant may not be as direct and effective as milling.
Flexibility and precision:
Milling teeth provides greater processing flexibility and precision control, which is critical to ensuring thread quality in adhesive materials. By finely adjusting cutting parameters, such as cutting speed and feed rate, material pulling and sticking can be minimized, thereby improving the overall quality of the thread.
Reduce tool wear:
Sticky materials can cause additional tool wear during machining. Milling teeth help slow tool wear and extend tool life by reducing material adhesion and providing better chip evacuation.