CNC programming problems and Solutions
来源： 作者： 发布日期：2021-06-27 访问次数：649
1. Workpiece overcutting:
reason:
1. The strength of the tool is not enough, too long or too small. This causes the tool to spring.
2. Improper operation of the operator.
3. The cutting allowance is not uniform（ For example: 0.5 for the side of the surface and 0.15 for the bottom)
4. Improper cutting parameters (such as too large tolerance, too fast SF setting, etc.).
improve:
1. The principle of using a knife: big but not small, short but not long.
2. Add the corner cleaning procedure, and keep the allowance as even as possible (the allowance of side and bottom is the same).
3. Reasonable adjustment of cutting parameters, large allowance, corner rounding.
4. Using SF function of machine tool, the operator can fine tune the cutting speed to achieve the best cutting effect.
2. In the middle of the score:
reason:
1. The operator's manual operation is not accurate, and the manual operation number is wrong.
2. There are burrs around the mold.
3. The center bar has magnetism.
4. The four sides of the mold are not vertical.
improve:
1. The manual operation should be carefully checked repeatedly, and the points should be at the same point and at the same height as far as possible.
2. Deburring the periphery of the mould with oilstone or file, wiping it with rag, and finally confirming with hand.
3. Demagnetize the center bar before centring the mold (ceramic center bar or others can be used).
4. Check whether the four sides of the die are vertical (the verticality error is large, so we need to review the scheme with the fitter).
3. Sword setting:
reason:
1. The operator's manual operation is not accurate, and the manual operation number is wrong.
2. Tool clamping error.
3. There is a mistake in the blade of the flying knife.
4. There are errors between R knife, flat bottom knife and flying knife.
improve:
1. The manual operation should be checked carefully repeatedly, and the knife should be set at the same point as far as possible.
2. When the cutter is clamped, use the air gun to blow clean or wipe clean with rags.
3. When the upper blade of the flying knife needs to measure the knife bar and smooth bottom surface, one blade can be used.
4. A single tool setting program can avoid the error between flat and flying r tool.
4. Collision programming:
reason:
1. The safety height is not enough or not set (the tool or collet collides with the workpiece during rapid feed G00).
2. The tool on the program list and the actual program tool are written incorrectly.
3. The tool length (edge length) and the actual machining depth on the program sheet are written incorrectly.
4. The depth z-axis access and the actual z-axis access on the program sheet are wrongly written.
5. The coordinate setting is wrong 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 automatic program list or picture program list).
3. Measure the actual machining depth on the workpiece, and write clearly the length and edge length of the tool in the program sheet (generally, the tool holder length is 2-3mm higher than the workpiece, and the edge length 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, written to check repeatedly).
V. Collision Operator:
reason:
1. Depth z-axis tool setting error.
2. The number of collision and operation errors (such as: unilateral access without feed radius, etc.).
3. Use wrong tool (e.g. D4 tool is processed with D10 tool).
4. The program goes wrong (for example, a7.nc goes to a9.nc).
5. The hand wheel is in the wrong direction during manual operation.
6. Press the wrong direction during manual rapid feeding (e.g.: - x press + x).
improve:
1. Depth z-axis tool setting must pay attention to the tool setting position（ Bottom surface, top surface, analysis surface, etc.).
2. Check the number of points and operations repeatedly.
3. When clamping the tool, check with the program list and program repeatedly before installing.
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 fast movement, the z-axis can be raised above the workpiece to move.
6. Surface accuracy:
reason:
1. The cutting parameters are unreasonable and the surface of workpiece is rough.
2. The cutting edge is not sharp.
3. The tool clamping is too long and the blade clearance is too long.
4. Chip removal, air blowing and oil flushing are not good.
5. Programming tool feed mode (can consider run-along milling as far as possible).
6. The workpiece has burr.
improve:
1. The setting of cutting parameters, tolerance, allowance, speed and feed should be reasonable.
2. The tool requires the operator to check and replace it irregularly.
3. The operator is required to clamp the tool as short as possible, and the blade should not be too long.
4. For flat knife, R knife, round nose knife cutting, speed feed settings should be reasonable.
5. Workpiece has burr: it is directly related to our machine tool, cutting tool and cutting way. So we need to understand the performance of the machine tool, the edge of the burr repair.
reason:
1. The strength of the tool is not enough, too long or too small. This causes the tool to spring.
2. Improper operation of the operator.
3. The cutting allowance is not uniform（ For example: 0.5 for the side of the surface and 0.15 for the bottom)
4. Improper cutting parameters (such as too large tolerance, too fast SF setting, etc.).
improve:
1. The principle of using a knife: big but not small, short but not long.
2. Add the corner cleaning procedure, and keep the allowance as even as possible (the allowance of side and bottom is the same).
3. Reasonable adjustment of cutting parameters, large allowance, corner rounding.
4. Using SF function of machine tool, the operator can fine tune the cutting speed to achieve the best cutting effect.
2. In the middle of the score:
reason:
1. The operator's manual operation is not accurate, and the manual operation number is wrong.
2. There are burrs around the mold.
3. The center bar has magnetism.
4. The four sides of the mold are not vertical.
improve:
1. The manual operation should be carefully checked repeatedly, and the points should be at the same point and at the same height as far as possible.
2. Deburring the periphery of the mould with oilstone or file, wiping it with rag, and finally confirming with hand.
3. Demagnetize the center bar before centring the mold (ceramic center bar or others can be used).
4. Check whether the four sides of the die are vertical (the verticality error is large, so we need to review the scheme with the fitter).
3. Sword setting:
reason:
1. The operator's manual operation is not accurate, and the manual operation number is wrong.
2. Tool clamping error.
3. There is a mistake in the blade of the flying knife.
4. There are errors between R knife, flat bottom knife and flying knife.
improve:
1. The manual operation should be checked carefully repeatedly, and the knife should be set at the same point as far as possible.
2. When the cutter is clamped, use the air gun to blow clean or wipe clean with rags.
3. When the upper blade of the flying knife needs to measure the knife bar and smooth bottom surface, one blade can be used.
4. A single tool setting program can avoid the error between flat and flying r tool.
4. Collision programming:
reason:
1. The safety height is not enough or not set (the tool or collet collides with the workpiece during rapid feed G00).
2. The tool on the program list and the actual program tool are written incorrectly.
3. The tool length (edge length) and the actual machining depth on the program sheet are written incorrectly.
4. The depth z-axis access and the actual z-axis access on the program sheet are wrongly written.
5. The coordinate setting is wrong 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 automatic program list or picture program list).
3. Measure the actual machining depth on the workpiece, and write clearly the length and edge length of the tool in the program sheet (generally, the tool holder length is 2-3mm higher than the workpiece, and the edge length 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, written to check repeatedly).
V. Collision Operator:
reason:
1. Depth z-axis tool setting error.
2. The number of collision and operation errors (such as: unilateral access without feed radius, etc.).
3. Use wrong tool (e.g. D4 tool is processed with D10 tool).
4. The program goes wrong (for example, a7.nc goes to a9.nc).
5. The hand wheel is in the wrong direction during manual operation.
6. Press the wrong direction during manual rapid feeding (e.g.: - x press + x).
improve:
1. Depth z-axis tool setting must pay attention to the tool setting position（ Bottom surface, top surface, analysis surface, etc.).
2. Check the number of points and operations repeatedly.
3. When clamping the tool, check with the program list and program repeatedly before installing.
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 fast movement, the z-axis can be raised above the workpiece to move.
6. Surface accuracy:
reason:
1. The cutting parameters are unreasonable and the surface of workpiece is rough.
2. The cutting edge is not sharp.
3. The tool clamping is too long and the blade clearance is too long.
4. Chip removal, air blowing and oil flushing are not good.
5. Programming tool feed mode (can consider run-along milling as far as possible).
6. The workpiece has burr.
improve:
1. The setting of cutting parameters, tolerance, allowance, speed and feed should be reasonable.
2. The tool requires the operator to check and replace it irregularly.
3. The operator is required to clamp the tool as short as possible, and the blade should not be too long.
4. For flat knife, R knife, round nose knife cutting, speed feed settings should be reasonable.
5. Workpiece has burr: it is directly related to our machine tool, cutting tool and cutting way. So we need to understand the performance of the machine tool, the edge of the burr repair.