1. Workpiece over cutting:
reason:
1. The tool strength is not too long or too small. Cause the tool to bounce.
2. Improper operator operation.
3. The cutting allowance is not uniform. (e.g. 0.5 for side of curved surface and 0.15 for bottom surface)
4. Improper cutting parameters (such as too large tolerance, too fast SF setting, etc.).
improve:
1. The principle of using knife: it can be big or small, short or not long.
2. Add corner clearance procedure, and the allowance should be uniform as far as possible (the allowance of side and bottom should be consistent).
3. Reasonable adjustment of cutting parameters, large margin corner rounding.
4. Using the SF function of the machine tool, the operator can adjust the speed to achieve good cutting effect.
2
reason:
1. The operator’s manual operation is not accurate and the number of manual operations is wrong.
2. There are burrs around the mold.
3. There is magnetism in the center rod.
4. The four sides of the mold are not vertical.
improve:
1. The manual operation should be checked carefully repeatedly, and the points should be at the same height as far as possible.
2. Deburring the periphery of the mould with an oilstone or file, wipe it with rags, and then confirm it by hand.
3. Demagnetize the center bar before parting the mold (ceramic bar or others can be used).
4. Check whether the four sides of the mould are vertical by checking the table (the verticality error is large, and the scheme should be reviewed with the fitter).
3. Knife setting:
reason:
1. The operator’s manual operation is not accurate and the number of manual operations is wrong.
2. Tool clamping error.
3. The blade on the flying knife is wrong (there is a certain error in the flying knife itself).
4. There is error between R knife and flat bottom knife and flying knife.
improve:
1. The manual operation should be checked repeatedly, and the tool setting should be at the same point as far as possible.
2. When clamping the cutting tools, blow them with air gun or wipe them with rags.
3. When the upper blade of flying knife needs to measure the cutter rod and smooth bottom surface, one blade can be used.
4. A tool setting program can avoid the error between the flying knives of R knife and flat knife.
4. Collision programming:
reason:
1. The safety height is not enough or not set (when the rapid feed G00, the cutter or chuck collides with the workpiece).
2. The tool on the program list is wrong with the tool in the actual program.
3. The tool length (edge length) and the actual machining depth on the program list are wrongly written.
4. The depth z-axis access on the program list is wrong with the actual z-axis.
5. Coordinate setting error during programming.
improve:
1. Accurate measurement of the height of the workpiece also ensures that the safe height is above the workpiece.
2. The tool on the program list should be consistent with the actual program tool (try to use the automatic program sheet or the picture to make the program list).
3. Measure the actual machining depth on the workpiece, and write the length and edge length of the tool clearly on the program sheet (generally, the length of the tool holder is 2-3mm higher than the workpiece, and the length of the blade is 0.5-1.0mm).
4. Take the actual z-axis data on the workpiece and write it clearly on the program sheet. (this operation is generally manual operation, and it should be checked repeatedly).
5. Collision Operator:
reason:
1. Depth z axis tool setting error.
2. The number of collisions and operation errors (such as: unilateral access without feed radius, etc.).
3. Use the wrong tool (e.g. D4 is processed with D10).
4. The program goes wrong (for example: a7.nc goes a9.nc).
5. The handwheel is in the wrong direction during manual operation.
6. Press the wrong direction during manual rapid feed (for example: – x press + x).
improve:
1. The depth z-axis tool setting must pay attention to the position of the tool. (bottom, top, analysis, etc.).
2. The number of collisions and operations should be checked repeatedly after completion.
3. When clamping the tool, check it with the program sheet and program repeatedly before installing it.
4. The program should go in order one by one.
5. When using manual operation, the operator should enhance the operation proficiency of the machine tool.
6. In manual rapid movement, the z-axis can be raised to the workpiece to move.
6. Surface accuracy:
reason:
1. The cutting parameters are unreasonable and the surface of workpiece surface is rough.
2. The cutting edge of the tool is not sharp.
3. The tool clamping is too long and the blade is too long.
4. Chip removal, air blowing and oil flushing are not good.
5. Programming tool feed mode, (can consider the following milling as far as possible).
6. The workpiece has burr.
improve:
1. Cutting parameters, tolerances, allowance, speed and feed settings should be reasonable.
2. The tool requires the operator to check and replace the tool from time to time.
3. The operator is required to clamp the tool as short as possible and the blade should not be too long.
4. For flat cutter, R knife and round nose knife, the speed feed setting should be reasonable.
5. Workpiece has burr: it is directly related to our machine tool, cutting tool and tool feeding mode. Therefore, we need to understand the performance of the machine tool, the edge of the burr repair
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