There are various tool setting methods for CNC lathes. The following are several common ones:
1.Trial cutting method:
This method is simple and convenient, but it will leave cutting marks on the surface of the workpiece and has relatively low tool setting accuracy.
The bilateral tool setting method is adopted, and the tool setting point (which coincides with the origin of the workpiece coordinate system here) is at the center of the workpiece surface.
The tool setting method using a feeler gauge, standard mandrel and gauge block is similar to this method, except that the spindle does not rotate during tool setting. A feeler gauge (or standard mandrel or gauge block) is added between the tool and the workpiece, with the feeler gauge not being able to move freely as the standard. Note that when calculating the coordinates, the thickness of the feeler gauge should be subtracted.
2.Edge finder and eccentric rod tool setting method:
The operation steps are similar to the trial cutting and tool alignment method, except that the tool is replaced with an edge finder or an eccentric rod.
When using an edge finder, one must be careful to ensure that the steel ball part makes slight contact with the workpiece. At the same time, the workpiece being processed must be a good conductor, and the positioning reference surface must have a good surface roughness.
3.Transfer (indirect) tool setting method:
When the workpiece needs to be clamped and processed multiple times, the transfer tool setting method can ensure the positional accuracy of each surface processed after each clamping.
4.The method of using a dial indicator (or dial indicator) for cutting:
It is generally used for tool setting of circular workpieces.
The dial indicator is fixed on the machine tool spindle. Turn the handwheel to make the spindle rotate forward and backward. Observe the deflection of the pointer and adjust the radial position of the tool so that the pointer points to the exact middle position. At this time, the radial position of the tool is adjusted properly.
5.Automatic tool offset setting method (selecting the reference tool as the standard tool) :
Use the reference tool to test cut the right end face of the workpiece and record the Z machine coordinate of the test cut point A.
Test cut the outer circle of the workpiece, record the X machine coordinate at point A, stop the machine after retracting the tool, and measure the outer diameter ΦD of the machined shaft section.
The reference knife returns to point A according to the recorded value through the "point movement + step" method. Enter ΦD and zero respectively in the trial cutting diameter and trial cutting length columns of the knife deviation table.
Replace the non-reference tools. Let the tip of each non-reference tool be visually aligned with point A under the rotation of the main shaft through the "point movement + step" method. Then, enter ΦD and zero respectively in the trial cutting diameter column and the trial cutting length column of the corresponding tool offset. The tool offset of each non-reference tool will be automatically displayed in the X and Z offset columns.
These tool setting methods each have their own advantages and disadvantages. The specific method to be used depends on factors such as processing requirements, workpiece material, and machine tool type. In actual operation, the appropriate tool setting method should be selected based on specific circumstances to ensure processing accuracy and efficiency. At the same time, safety should be noted during the knife setting process to avoid any accidents.
