How do you handle these problems that occur during CNC machining?

1, Workpiece over cutting:
Reason:
1. The tool strength is not too long or too small, resulting in the tool bouncing.
2. Improper operation by the operator.
3. Uneven cutting allowance. (For example, leave 0.5 on the side of the curved surface and 0.15 on the bottom)
4. Improper cutting parameters (such as too large tolerance, SF setting too fast, etc.).
Improvement:
1. The principle of using a knife: it can be big but not small, and it can be short but not long.
2. Add a corner cleaning program and leave the margin as evenly as possible (with consistent margin on both sides and bottom).
3. Reasonably adjust cutting parameters and round corners with large margin.
4. By utilizing the SF function of the machine tool, the operator can adjust the speed to achieve the best cutting effect.
2, Split in question:
Reason:
1. Inaccurate manual operation by the operator.
2. There are burrs around the mold.
3. The dividing rod has magnetism.
4. The four sides of the mold are not perpendicular.
Improvement:
1. Manual operation should be carefully checked repeatedly, and the center should be at the same point and height as much as possible.
2. Use an oilstone or file to remove burrs around the mold, wipe it clean with a rag, and finally confirm by hand.
3. Before dividing the mold, demagnetize the dividing rod (using ceramic dividing rods or other materials).
4. Check if the four sides of the mold are vertical with the calibration table (if there is a large error in verticality, it is necessary to review the plan with the fitter).
3, Knife alignment issue:
Reason:
1. Inaccurate manual operation by the operator.
2. Incorrect tool clamping.
3. The blade on the flying knife is incorrect (the flying knife itself has a certain degree of error).
4. There is an error between the R knife and the flat bottomed knife and the flying knife.
Improvement:
1. Manual operation should be carefully checked repeatedly, and the knife should be aligned at the same point as much as possible.
2. When clamping the cutting tools, use an air gun to blow them clean or wipe them clean with a cloth.
3. When measuring the blade on the flying knife, one blade can be used to measure the blade holder and the bottom surface.
4. Create a separate tool alignment program to avoid errors between the flat and flying blades of the R blade.
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4, Collision - Programming:
Reason:
1. The safety height is insufficient or not set (when the tool or chuck collides with the workpiece during rapid feed G00).
2. The tool on the program sheet and the actual program tool are written incorrectly.
3. The tool length (blade length) and actual machining depth on the program sheet are written incorrectly.
4. The depth Z-axis retrieval and actual Z-axis retrieval on the program sheet are written incorrectly.
5. Coordinate setting error during programming.
Improvement:
1. Accurately measuring the height of the workpiece also ensures that the safe height is above the workpiece.
2. The tools on the program sheet should be consistent with the actual program tools (try to use automatic program sheets or use pictures to create program sheets).
3. Measure the actual depth of machining on the workpiece, and clearly write the length and blade length of the tool on the program sheet (usually the tool clamp length is 2-3mm higher than the workpiece, and the blade length is 0.5-1.0mm away from the blank).
4. Take the actual Z-axis data on the workpiece and write it clearly on the program sheet. (This operation is usually manual and needs to be checked repeatedly.).
5, Collision - Operator:
Reason:
1. Depth Z-axis tool alignment error.
2. Errors in the number of hits and operations during the division (such as unilateral data retrieval without feed radius, etc.).
3. Using the wrong knife (such as using D10 knife for machining with D4 knife).
4. Program error (e.g. A7. NC went to A9. NC).
5. The handwheel was turned in the wrong direction during manual operation.
6. Press the wrong direction during manual rapid feed (such as - X pressing+X).
Improvement:
1. Be sure to pay attention to the position of the tool when aligning the depth Z-axis. (Bottom, top, analysis surface, etc.).
2. Repeated checks should be carried out after the completion of the division, collision, and operation.
3. When clamping the tool, it is necessary to repeatedly check and compare it with the program sheet and program before installing it.
4. The program needs to be executed in sequence one by one.
5. When using manual operation, the operator should enhance the proficiency of the machine tool operation.
6. When manually moving quickly, the Z-axis can be raised above the workpiece before moving.
6, Surface accuracy:
Reason:
1. The cutting parameters are unreasonable, and the surface of the workpiece surface is rough.
2. The cutting edge of the tool is not sharp.
3. The tool clamping is too long, and the blade avoidance is too long.
4. Removing debris, blowing air, and flushing oil are not good.
5. Programming the cutting method, (consider smooth milling as much as possible).
6. The workpiece has burrs.
Improvement:
1. Cutting parameters, tolerances, allowances, and speed feed settings should be reasonable.
2. The tool requires the operator to inspect and replace it irregularly.
3. When clamping the tool, the operator is required to clamp it as short as possible and the blade should not be too long in the air.
4. For the downward cutting of flat, R, and round nose knives, the speed and feed settings should be reasonable.
5. The workpiece has burrs: it is directly related to our machine tool, cutting tool, and cutting method. So we need to understand the performance of the machine tool and make up for burrs on the edges.