Category Archive CNC Technology

Computer gong processing spindle

CNC engraving machine is mainly composed of machine tool, spindle, gantry, control system, transmission system and so on. CNC engraving machine spindle motor is also divided into precision machining spindle and high-power cutting spindle. 1. CNC engraving machine fine machining spindle is characterized by low noise, high speed, high height, suitable for processing special fine workpieces, such as seals, nameplates, badge gifts, etc. Dongguan computer gong processing | Dongguan Mechanical parts processing | Dongguan precision computer gong processing | Dongguan high-speed computer gong processing | this kind of CNC engraving machine spindle motor is usually high-speed frequency conversion motor, the power is lower than 250W. The disadvantage is that the ability to cut thick materials is poor, not suitable for cutting thick materials. 2. CNC engraving machine high-power cutting spindle, mainly used for cutting, high-power engraving, is characterized by high power, strong cutting ability, especially suitable for cutting Yu, three-dimensional characters, of course, can also make chest plates, nameplates, seals, etc. Dongguan computer gong processing, Dongguan Mechanical parts processing, Dongguan precision computer gong processing, Dongguan high speed computer gong processing, this kind of CNC engraving machine high-power spindle can be generally divided into brushless frequency high-speed AC motor and brush AC machine according to the characteristics of the motor. The main differences are: a. the speed of brushless variable frequency motor is high, the speed range is 70060000 rpm, and the maximum speed of general brush AC motor is not more than 24000 rpm. B. The brushless variable frequency motor has the advantages of high rotation accuracy, low wear and low noise. The noise is much lower than that of the brush AC motor. C. Due to the special current limiting circuit on the frequency converter, the motor will not be burned after a short period of time due to the special current limiting circuit on the frequency converter. However, the brush AC machine will quickly smoke and burn out when it is overloaded or locked in the process of computer gong processing, and it can not be repaired. D. The brushless variable frequency motor adopts frequency conversion control technology for speed regulation, which is a professional product. Dongguan computer gong processing, Dongguan Mechanical parts processing, Dongguan precision computer gong processing, Dongguan high-speed computer gong processing, has a long service life. The CNC engraving machine manufacturer provides one year free replacement. In the future, the motor can be maintained by replacing the high-speed bearing, while the brush AC motor has a long service life due to the use of electric documents It takes about 300 hours to replace the motor or motor carbon brush, so the carbon brush AC motor is usually not guaranteed for a day.

报错 笔记

Computer gong processing program

1、 Start up processing:

  1. At the beginning of each program, it is necessary to carefully check whether the tool used is the one specified in the programming instruction. When Dongguan computer gong processing starts, the feed speed should be adjusted to the minimum and executed in single section. Attention should be paid to the stop key when fast positioning, cutting and feeding. The hand should be placed on the stop key. If there is any problem, stop immediately. Pay attention to observe the moving direction of the tool to ensure safe feeding. Shenzhen computer gong processing will slowly increase the feed speed to the appropriate level. At the same time, coolant or cold air should be added to the cutter and workpiece 。
  2. During rough machining, it should not be too far away from the control panel. If there is any abnormal phenomenon, stop the machine in time for inspection.
  3. After roughening, pull the meter again to make sure that the workpiece is not loose. If there is a side, it must be corrected and bumped again.
  4. Dongguan high-speed computer gongs processing in the process of continuous optimization of processing parameters, to achieve the best processing effect.
  5. Since this process is a key process, the main dimension value of the workpiece shall be measured to see if it is consistent with the requirements of the drawing. If there is any problem, it shall be immediately notified to the team leader or programmer for inspection and solution. It can be removed after passing the self inspection and sent to the inspector for special inspection.
  6. Clean the machine table in time after the workpiece is removed.
  7. Processing type;
  8. Hole machining;
  9. Drilling processing: before drilling, the center drill must be used for positioning, and then the drill bit which is 0.5 ~ 2mm smaller than the drawing size should be used for drilling, and finally the appropriate drill bit should be used for finishing.
  10. Reaming processing: for the reaming of the workpiece, the center drill shall be used for positioning, and then the drill bit 0.5 ~ 0.3 mm smaller than the drawing size shall be used for drilling, and finally the reamer shall be used for reaming. During reaming, the spindle speed shall be controlled within 70 ~ 180 RPM / min.
  11. Boring processing: for the boring of the workpiece, the center drill shall be used for positioning, and then the drill bit which is 1 ~ 2mm smaller than the drawing size shall be used for drilling, and then the rough boring cutter (or milling cutter) shall be used to process the remaining machining allowance of about 0.3mm on one side. Finally, the fine boring cutter with pre adjusted size shall be used for fine boring, and the final fine boring allowance shall not be less than 0.1mm.
  12. Direct numerical control (DNC) operation;
  13. Before DNC NC machining, the workpiece should be clamped, the zero position should be set and the parameters should be set.
  14. Open the processing program to be transferred in the computer for checking, and then let the computer enter the DNC state, and input the file name of the correct processing program.
  15. Press the tape key and program start key on the machine tool, and the machine tool controller will flash LSK when machining the mechanical parts in Dongguan.
  16. The DNC data transmission processing can be carried out by pressing the enter keyboard on the computer.

2、 Contents and scope of self inspection of workers:

  1. Before processing, the processor must clearly see the content of the process card, clearly know the parts, shapes and dimensions of the workpiece to be processed, and know the processing content of the next process.
  2. Before clamping the workpiece, the blank size should be measured to see if it meets the requirements of the drawing, and the placement of the workpiece must be carefully checked whether it is consistent with the programming operation instruction.
  3. Self inspection should be carried out in time after rough machining, so as to adjust the data with errors in time. The self inspection content mainly includes the position and size of the processing parts. For example: (1) whether the workpiece is loose; (2) whether the workpiece is correctly divided; (3) whether the dimension from the processing part to the reference edge (reference point) meets the requirements of the drawing; (4) the position size between the processing parts. After checking the position and size of bulk machining parts, the rough machined shape ruler should be measured (except for arc).
  4. After rough machining self inspection, finish machining is carried out. After finishing, the workers should check the shape and size of the processing parts: check the basic length and width of the vertical processing parts; measure the base point size marked on the drawing for the processing parts of the inclined plane.
  5. The worker completes the workpiece self inspection.

Notes on starting computer gong

  1. After starting the machine or pressing the emergency stop to reset each time, the computer gong processing machine tool first returns to the reference zero position of the machine tool (i.e. return to zero), so that the machine tool has a reference position for its future operation.
  2. Clamping workpiece:
  3. Before the workpiece is clamped, the surface should be cleaned, and there should be no oil stain, iron filings and dust during the machining of Dongguan Mechanical parts, and the burr on the surface of the workpiece should be removed with a file (or oilstone).
  4. The equal high-speed rail used for clamping must be grinded flat by grinding machine to make it smooth and flat. The weight iron and nut must be firm, which can reliably clamp the workpiece. For some small workpieces that are difficult to be clamped, they can be directly clamped on the vise.
  5. The worktable of the machine tool shall be clean and free of iron filings, dust and oil stains.
  6. The pad iron is generally placed at the four corners of the workpiece, and equal height pad iron should be added in the middle of the workpiece with too large span.
  7. Check the length, width and height of the workpiece with a ruler according to the size of the drawing.
  8. When clamping the workpiece, according to the clamping and placing mode in the programming operation instruction, it is necessary to consider avoiding the processing position and the situation that the cutter head may encounter the fixture during the processing.
  9. After the workpiece processed by Dongguan precision computer gong is placed on the pad iron, the gauge shall be drawn according to the drawing requirements. The error of workpiece length direction is less than 0.02mm, and the horizontal error of top surface in X and Y direction is less than 0.05mm. The perpendicularity of the workpiece which has been ground on six sides shall be checked to see if it is qualified.
  10. After pulling the watch, the nut must be tightened to prevent the workpiece from shifting during processing due to the loose clamping.
  11. Pull the meter again to make sure that the error does not exceed the tolerance after clamping.
  12. Workpiece collision number: for the clamped workpiece, the collision number head can be used to determine the processing reference zero position. There are two kinds of collision head, photoelectric type and mechanical type. There are two kinds of collision selection methods: middle collision number and single side collision number. The steps are as follows:
  13. Collision counting method: photoelectric static, mechanical speed 450 ~ 600 rpm.
  14. Manually move the x-axis of the worktable to make the colliding head touch one side of the workpiece. When the collision head just touches the workpiece and the red light is on, set the relative coordinate value of this point as zero; then manually move the x-axis of the workbench to make the collision head collide with the other side of the workpiece, and record the relative coordinates when the collision head just touches the work piece.
  15. According to the relative value minus the diameter of the bumping head (i.e. the length of the workpiece), check whether the length of the workpiece meets the requirements of the drawing.
  16. Divide the relative coordinate number by 2, and the value is the middle value of the x-axis of the workpiece. Then move the worktable to the middle value on the x-axis, and set the relative coordinate value of the x-axis at this point to zero, which is the zero position on the x-axis of the workpiece.
  17. Carefully record the mechanical coordinate value of the zero position on the x-axis of the workpiece in one of g54 ~ G59, and let the machine tool determine the zero position on the x-axis of the workpiece. Once again, check the correctness of the data carefully.
  18. The steps of setting the zero position of workpiece Y axis are the same as those of X axis.
  19. Prepare all tools according to the programming instruction.
  20. Dongguan high-speed computer gong machining according to the tool data in the programming operation instruction, change the tool to be processed, and let the tool touch the height measuring device placed on the datum plane. When the red light of the measuring instrument is on, set the relative coordinate value of this point to zero.
  21. Move the tool to a safe place, manually move the tool down by 50mm, and set the relative coordinate value of this point to zero, which is the zero position of Z axis.
  22. Record the mechanical coordinate Z value of this point in one of g54 ~ G59. This completes the zero setting of the X, y, z axes of the workpiece. Once again, check the correctness of the data carefully.
  23. The one-sided collision also touches one side of x-axis and Y-axis of the workpiece according to the above method. Offset the relative coordinate value of x-axis and y-axis at this point. The radius of collision head is the zero position of x-axis and y-axis. Finally, the mechanical coordinates of x-axis and y-axis are recorded in one of G54-G59. Once again, check the correctness of the data carefully.
  24. Check the correctness of the zero point, move the X and Y axes to the side suspension of the workpiece, and visually inspect the correctness of the zero point according to the size of the workpiece.
  25. Copy the program files to the computer according to the file path of the programming work instruction.
  26. Setting of processing parameters.
  27. Setting of spindle speed in machining.

How to improve the finish of computer gongs

Computer gongs processing patterns, finish is not high. There are many factors. If you are a long shaft type, it may be that the jacking force of the tailstock is not enough, or the tailstock is moving. If the tailstock has no problem, the tool wear, including processing parameters, cutting fluid and other issues, may occur. There is also the material of the part, the corresponding selection tool. In addition, including the problems of the machine tool itself, Dongguan computer gong processing, which can only be solved in practice, there is no way to solve, I hope you can find the reason

The main reason is because of the processing strength problem, it may be that the length of your processing parts is too long, or the length of your cutting tool is too long. The center height of the tool. Choose the right tool. Some are too high speed caused by the machine tool and parts of the resonance of the cutting tool will also appear patterns.

How to improve the finish of lathe processing?

First of all, you should ensure the stability of the lathe, that is, whether the fixed condition of the lathe is good.

What’s more, will the spindle vibrate at high speed,

Secondly, coolant is very important

In addition, your tool should be well ground, and the chip removal groove should be opened to prevent the workpiece from scraping due to unsmooth chip discharge, and the arc angle should be made when the turning tool is chamfered. In addition, when installing the tool, do not resist the tool.

Finally, it is necessary to match the spindle speed and feed speed. If your lathe is not working well, it is recommended to buy some sandpaper to make it. When making sandpaper, it is suggested to deal with it according to the working direction of the turning tool. In this way, the texture can be seen better

Matters needing attention in the processing of computer gongs

  1. When processing parts, the protective door must be closed. It is not allowed to stretch the head and hand into the protective door. It is not allowed to open the protective door during processing;
  2. In the process of processing, the operator shall not leave the machine without authorization, and shall keep a high degree of concentration. Dongguan computer gong processing, Dongguan Mechanical parts processing, Dongguan precision computer gong processing, Dongguan high-speed computer gong processing, shall observe the operation state of the machine tool. In case of any abnormal phenomenon or accident, the program operation shall be terminated immediately, the power supply shall be cut off and the instructor shall be informed in time. No other operation shall be carried out;
  3. It is strictly forbidden to beat the control panel and touch the display screen. It is strictly forbidden to knock the worktable, dividing head, clamp and guide rail;
  4. It is forbidden to open the control cabinet of CNC system to watch and touch without permission;
  5. The operator shall not change the internal parameters of the machine tool at will. Interns are not allowed to transfer or modify other programs that are not compiled by themselves;
  6. On the control computer of machine tool, no other operation is allowed except program operation, transmission and program copy;
  7. CNC milling machine is a kind of large precision equipment. Except for the tooling and workpieces placed on the worktable, it is strictly forbidden to stack any tools, clamps, edges, measuring tools, workpieces and other sundries on the machine tool;
  8. It is forbidden to touch the blade tip and iron filings by hand. Iron scraps must be cleaned with iron hook or brush;
  9. It is forbidden to touch the rotating spindle, workpiece or other moving parts by hand or any other means;
  10. It is forbidden to measure the workpiece and change the speed manually in the process of processing. It is not allowed to wipe the workpiece with cotton thread or clean the machine tool;

Advantages of computer gong processing device

Advantages: 1. High reliability

The reliability of large-scale mechanical parts processing equipment is guaranteed by using highly integrated electronic components, chips and VLSI.

Many functions are realized by software, which reduces the number of hardware.

Rich fault diagnosis and protection functions (mostly realized by software) can reduce the frequency of system failure and the repair time after failure.

  1. Easy to use and maintain

Easy to operate and use: Dongguan computer gong processing users only need to follow the menu prompts, you can operate correctly.

Easy to program: with a variety of programming functions, automatic program verification and simulation functions.

Convenient maintenance and repair: some routine maintenance work is carried out automatically (lubrication, regular inspection of key components, etc.), and the self diagnosis function of CNC machine tool can quickly realize accurate fault location.

  1. Easy to realize mechatronics

The small volume of CNC system control cabinet (using computer, the number of hardware is reduced; the integration of electronic components is higher and higher, and the hardware is constantly decreasing), which makes it possible to combine it with machine tool in physics, reduce the floor area and facilitate operation.

  1. Flexibility and versatility

The functions of Dongguan machine parts processing device are mostly realized by software, and the software and hardware adopt modular structure, which makes the modification and expansion of system functions more flexible.

The basic configuration of Dongguan machine parts processing device is universal. Different CNC machine tools only configure corresponding specific function modules to achieve specific control functions.

  1. Rich CNC functions

Interpolation function: quadratic curve, spline, spatial surface interpolation

Compensation function: motion precision compensation, random error compensation, nonlinear error compensation, etc

Man machine dialogue function: dynamic and static tracking display of processing, advanced man-machine dialogue window

The NC machining steps of parts are as follows:

① According to the drawing and process plan of the parts to be processed, the processing program is written with the specified code and program segment format; ② the written processing program instruction is input into the CNC device of the machine tool; ③ after the NC device processes the program (code), it sends control signals to the servo drive mechanism and auxiliary control device of each coordinate of the machine tool; ④ the servo mechanism receives the execution letter After No. 1 command, the machine drives all moving parts of the machine tool and controls the required auxiliary actions; 5) the machine tool automatically processes qualified parts;

1. Stipulation of machine tool coordinate system

The Cartesian and Z coordinate systems are determined by the Cartesian coordinate system and the right-hand coordinate system

The thumb, index finger and middle finger of the right hand are 90 ° to each other. The thumb represents the X coordinate, the index finger represents the Y coordinate, and the middle finger represents the Z coordinate;

The thumb points in the positive direction of X coordinate, the index finger points in the positive direction of Y coordinate, and the middle finger points in the positive direction of Z coordinate;

1. Stipulation of machine tool coordinate system

The Cartesian and Z coordinate systems are determined by the Cartesian coordinate system and the right-hand coordinate system

The thumb, index finger and middle finger of the right hand are 90 ° to each other. The thumb represents the X coordinate, the index finger represents the Y coordinate, and the middle finger represents the Z coordinate;

The thumb points in the positive direction of X coordinate, the index finger points in the positive direction of Y coordinate, and the middle finger points in the positive direction of Z coordinate;

3. Workpiece coordinate system and program origin

Definition: the workpiece coordinate system is used by the programmer when programming. The programmer selects a point on the workpiece as the origin (also known as the program origin), and establishes a coordinate system, which is called the workpiece coordinate system. Once the workpiece coordinate system is established, it will remain valid until it is replaced by a new one.

CNC machining features:

1. High machining precision

It is generally between 0.001-0.1mm. Not affected by the complexity of parts, automatic compensation.

2. Stable quality

For the same batch of parts, the machining path is identical, avoiding human error. Part one

The quality is stable.

3. High production efficiency

Large cutting parameters, automatic speed change, automatic tool change and other auxiliary operation automation are adopted

Function; the auxiliary time is greatly shortened (omitting marking work, reducing fixture design and adjustment,

There is no need for inspection and measurement between processes), and the productivity is 3-4 times higher. Spindle speed and feed range

Larger than ordinary machine tools.

4. Flexibility and adaptability

When the multi axis linkage and changing the machining parts, only the NC program needs to be replaced. Adapt to many varieties and small batch

Mass production.

5. It can realize multi-purpose and centralized operation

Automatic tool change machining center, in the case of clamping, can almost complete the parts

All processes. Reduce clamping error and save transportation, measurement and clamping between working procedures

Wait for auxiliary time.

6. Reduce labor intensity and improve working conditions

Automatic continuous processing simplifies the operation of workers and greatly reduces the labor intensity.

7. It is conducive to production management

It can accurately calculate the working hours, reduce the management of fixtures and semi-finished products, and reduce misoperation.

8. It is conducive to the development of computer control and management.

Digital signal is used to describe and control, based on program processing, which is convenient for computer networking and realize set

Medium control and management

9. It can reduce the production cost of the enterprise, improve the economic benefit of the enterprise, the quick response ability of the market and the competitiveness.

High quality, investment and management of maintenance personnel

Summary of NC machining:

1、 Question: how to divide the process?

Answer: generally, the division of NC machining process can be carried out according to the following methods:

(1) Tool centralized sorting method is to divide the process according to the tool used, and use the same tool to process all the parts that can be completed. Use a second knife, a third knife to do whatever else they can. In this way, the number of tool changes can be reduced, the idle travel time can be compressed, and the unnecessary positioning error can be reduced.

(2) According to the structural characteristics of the parts, the processing parts can be divided into several parts, such as inner shape, shape, surface or plane. Generally, the plane and positioning surface are processed first, and then the hole; the simple geometric shape is processed first, and then the complex geometric shape; the parts with low precision are processed first, and then the parts with high precision requirements are processed.

(3) According to the method of rough and finish machining, the parts which are easy to deform need to be adjusted because of the possible deformation after rough machining, so generally speaking, the working procedure should be separated for rough and finish machining.

To sum up, in the division of working procedures, it is necessary to flexibly master the structure and technology of parts, the function of machine tools, the number of NC machining contents of parts, installation times and the production organization of the unit. In addition, it is suggested that the principle of process centralization or process decentralization should be adopted according to the actual situation, but it must be reasonable.

2、 Q: what principles should be followed in the arrangement of processing sequence?

Answer: the arrangement of processing sequence should be considered according to the structure and blank condition of parts, as well as the need of positioning and clamping. The key point is that the rigidity of the workpiece will not be damaged. Generally, the sequence should be carried out according to the following principles:

(1) The processing of the previous process cannot affect the positioning and clamping of the next process, and the machining process of general machine tool should be considered comprehensively.

(2) The inner shape and inner cavity processing sequence is carried out first, and then the contour processing process is carried out.

(3) In order to reduce the times of repeated positioning, tool changing and pressing plate moving, the same positioning and clamping methods or the same tool processing process should be well connected.

(4) For multiple procedures in the same installation, the process with less damage to the rigidity of the workpiece should be arranged first.

3、 Question: which aspects should be paid attention to in determining the clamping mode of workpiece?

A: in determining the positioning reference and clamping scheme, the following three points should be noted:

(1) Strive to design, process, and programming calculation of the benchmark unity.

(2) The clamping times should be reduced as much as possible, and all the surfaces to be machined can be processed after one positioning.

(3) Avoid using manual adjustment plan.

(4) The fixture shall be open, and its positioning and clamping mechanism shall not affect the tool feeding during processing (such as collision). In case of such situation, the vise or bottom plate drawing screw can be used for clamping.

4、 Question: how to determine the tool setting point is reasonable? What is the relationship between workpiece coordinate system and programming coordinate system?

1. The tool setting point can be set on the part to be processed, but pay attention to that the tool setting point must be the reference position or the position that has been finished. Sometimes, the tool setting point will be damaged after the × * * process, which will make the second process and the subsequent tool setting point impossible to find. Therefore, when setting the tool in the × * * process, it is necessary to set up a relative tool setting where there is a relatively fixed dimension relationship with the positioning reference In this way, the original tool setting point can be retrieved according to the relative position relationship between them. This relative tool setting position is usually set on the machine tool table or fixture. The selection principles are as follows:

1) It’s easy to find the right one.

2) Programming is convenient.

3) The tool setting error is small.

4) It is convenient to check during processing.

2. The origin position of the workpiece coordinate system is set by the operator himself. After the workpiece is clamped, it is determined by tool setting. It reflects the distance position relationship between the workpiece and the zero point of the machine tool. Once the workpiece coordinate system is fixed, it is generally not changed. The workpiece coordinate system and the programming coordinate system must be unified, that is, during machining, the workpiece coordinate system and the programming coordinate system are consistent.

5、 Question: how to choose the cutting route?

Tool path refers to the path and direction of the tool relative to the workpiece in the process of NC machining. The reasonable choice of machining route is very important because it is closely related to the machining accuracy and surface quality of parts. The following points are mainly considered in determining the tool path:

1) Ensure the machining accuracy of parts.

2) It is convenient for numerical calculation and reduces the workload of programming.

3) To find a short processing route, reduce the idle time to improve processing efficiency.

4) Minimize the number of program segments.

5) To ensure the surface roughness of workpiece contour after machining, the final contour should be processed continuously by the next tool feed.

6) The tool’s advance and retreat (cut in and cut out) routes should also be carefully considered, so as to minimize tool marks caused by tool stopping (elastic deformation caused by sudden change of cutting force) at the contour, and to avoid scratching the workpiece due to vertical cutting on the contour surface.

6、 Q: how to monitor and adjust during machining?

After the alignment and program debugging are completed, the workpiece can enter the automatic processing stage. In the process of automatic machining, the operator should monitor the process of cutting to prevent the quality problems and other accidents caused by abnormal cutting.

On the cutting process

CNC processing skills:

1. The speed of white steel knife should not be too fast.

2. Copper roughing less white steel knife, more use flying knife or alloy knife.

3. When the workpiece is too high, it should be sliced with different length of knife.

4. After roughening with a big knife, use a small knife to remove the remaining material to ensure that the allowance is consistent.

5. The plane should be processed with flat bottom cutter and less ball cutter to reduce the processing time.

6. When the copper worker cleans the angle, first check the size of R on the angle, and then determine how large the ball knife is used.

7. The four corners of the calibration plane should be smooth.

8. If the slope is an integer, use the slope cutter to process, such as pipe position.

9. Before each process, think about the remaining allowance after the previous process, so as to avoid empty cutter or excessive machining.

10. Try to take simple cutting path, such as shape, grooving, single side, less walking around the same height.

11. When taking wcut, if you can walk finish, don’t go rough.

12. When the shape of the light knife is smooth, first rough and then fine. When the workpiece is too high, polish the edge first and then the bottom.

13. Set tolerance reasonably to balance machining accuracy and computer calculation time. The tolerance is set to 1 / 5 of the allowance for roughening and 0.01 for smooth knife.

14. Do more procedures to reduce the time of empty knife. Think more and reduce the chance of making mistakes. Make more auxiliary lines and auxiliary surfaces to improve the processing condition.

15. Establish a sense of responsibility and check each parameter carefully to avoid rework.

16. Be diligent in learning, good at thinking and make continuous progress. When milling non flat surface, use ball cutter more, use less end knife, do not be afraid to connect knife; small knife angle cleaning, big knife finishing; don’t be afraid of patching, proper patching can improve the processing speed and beautify the processing effect.

17. High hardness of blank material:

Better up milling, lower hardness of blank material: better forward milling, better machine tool precision, good rigidity, finish machining: more suitable for forward milling, vice versa, more suitable for finish machining of inner corner of parts by up milling. It is strongly recommended to use forward milling. Rough machining: reverse milling is better, finish machining is better: down milling is better, tool material toughness is good, hardness is low: it is more suitable for rough machining (large cutting amount processing), tool material toughness is poor, hardness is high: it is more suitable for finishing (small cutting amount processing).

18. Copper processing methods and precautions:

Before writing the cutter path, after the three-dimensional drawing is finished, the graphic center should be moved to the coordinate origin, and the high point should be moved to Z = 0 before machining. The copper male spark position can process negative reservation. Before processing, it is also necessary to check whether the clamping direction of the workpiece is the same as the graphic direction in the computer, whether the arrangement in the mold is correct, whether the fixture hinders the processing, and whether the direction of the front and rear dies match. Also check whether the tools you use are complete, and check the benchmark in the calibration table. Matters needing attention in copper processing: for the determination of spark position, the reserved amount of young male (i.e. fine male) is 0.05 ~ 0.15 and coarse male is 0.2 ~ 0.5. The specific spark position can be determined by the mold maker. Copper public has no dead corner that cannot be processed. Whether it is necessary to dismantle one more loose one. Generally, the cutter path of copper processing is as follows: big knife (flat knife) roughening – small knife (flat knife) angle clearing – ා 0; smooth knife uses spherical knife to smooth curved surface. In general, teachers use a flat knife instead of a ball knife. After a big knife, they use a small knife to make a rough cut. Then they use a large ball knife to smooth the surface, and then use a small ball knife to smooth the surface. It is not easy to use a small knife to process the dead angle that the big knife can’t pass for some small angles. It is advisable to limit the range of the knife’s travel so as to avoid too many empty knives. Copper, especially Yougong, requires high precision. The tolerance is generally 0.005 ~ 0.02 and the step distance is 0.05 ~ 0.3. When the copper is exposed to be thick, the tool passing position of the ball cutter position should be reserved, that is, the copper male shape should be opened to a depth of a knife radius. In general, the copper worker must have three datum planes when calibrating three surfaces (upper, lower, left and right). Copper material is easy to process. The feed speed and rotation speed can be faster. When roughing, the machining allowance is 0.2 ~ 0.5. Depending on the size of the workpiece, the machining allowance is large, so the cutting can be fast and the efficiency can be improved. Note: the brackets are the parameters of high-speed steel knife for steel roughening, and the above cutting speed refers to that the required profile f = 300 ~ 500, and the steel smooth cutter f = 50 ~ 200.

19. Problems of front die opening:

First of all, rotate the Copper drawing 180o in the front view or side view to turn it into the front mold drawing, and of course, add the pillow position and PL surface. If the original body needs to be reserved, do not use the mirror body method to change the Copper drawing into the front model drawing, which may be wrong (when the X direction and Y direction of the Copper drawing are asymmetric). There are two difficulties in front mold processing: the material is relatively hard; the front mold can not be easily welded and wrong. The principle of using a knife for roughening the front die is similar to that of a copper tool. However, a large knife should be used as far as possible for the front die, rather than a too small knife. It is easy to snap the knife. Generally, the handle () is used for roughening, and the round nose knife is also used for the smooth knife. Because this kind of knife is large and powerful, there is usually a problem when processing the front die with parting surface The parting surface should be accurate because of the impact of the machine, and the cavity should be left 0.2 ~ 0.5 machining allowance (reserved for spark). In this way, the surface of the die cavity can be corrected by 0.2 ~ 0.5 towards the positive direction, and the machining allowance can be set to 0 when the face is writing the tool path. When the front die is roughened or polished, it is usually necessary to limit the cutting range. Remember that the range you set is the range of the tool center, not the range of the tool boundary, not the range of the tool processing, but a larger tool radius. The common tool path method of front die roughening is surface grooving and parallel light knife. The front mold processing time division surface, the pillow position surface generally must process to the standard number, but the collision surface may leave 0

Solutions to problems in CNC machining:

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