Control Method for Machining CNC Lathe Turning Shaft Part with high accuracy
The precision CNC turned shaft part is a general category of CNC machining capability, but some precision requirements are rather demanding according to project type like +/-0.002MM on diameter and high polishing degree, so how to control it?
Taking CNC turning shaft parts as an example, usually we take remaining amount of 1mm as the tool compensation before first rough machining, and what is the remaining amount after processing? If the precision machining allowance is 0.98mm, with the tolerance with 0.04mm, for easy calculation, we take the intermediate value of the tolerance 0.02mm, plus the precessing allowance as 1mm. Finally, with 2 separate turning process, each radial feed is 0.5mm. If the remaining amount for work piece is 0.5mm after finishing the first roughing process, then the accuracy after the second turning should be qualified!
Why divide the turning into three steps, the first roughing step removes the remaining material, and the other two operations ensure the accuracy, because the spindle speed of the first processing is improved relative to the first roughing process, and the error of the machine precision is prevented. The next 2 steps can solve this problem. However, the second finishing feedrate can not be adjusted! Then accurate tolerances can be assured.