Engineering Blog

How to become a CNC master


To develop the equipment manufacturing industry, CNC machine tools are the foundation. CNC machine tools are the working machine of the equipment manufacturing industry. The revitalization of each field requires a large number of advanced CNC machine tools to equip it. In recent years, the output of CNC machine tools in China has continued to grow, and the CNC machine tools and delrin machining system industries will develop rapidly.
Many production workshops are equipped with CNC machine tools. One can imagine the importance of CNC machine tools. I want to know, how can I master the programming technology of CNC machine tools and become a master of CNC machine programming?
The editor believes that the programming technology of CNC machine tools can not be learned in a short time, it needs to learn step by step and accumulate experience slowly. To master this technology proficiently, you must have the theoretical level of an engineer, as well as the practical experience and hands-on ability of a senior technician.
1. Craft is the basis of programming. If you don’t understand the craft, you can’t say that you can program. Therefore, if you want to master the programming technology of titanium machining tools, you must first be an excellent craftsman.
CNC machine tools integrate drilling, milling, boring, reaming, tapping and other processes. The technical literacy requirements of the craftsman are very high. Numerical control program is to use computer language to embody the process of processing technology. Craft is the basis of programming. If you don’t understand the craftsmanship, you can never say that you know how to program.
In fact, when we choose the profession of mechanical cutting, it means that the early career is difficult and rough. The basic knowledge learned in the university is pitiful to meet the needs of the factory. Engineers of mechanical processing are, to some extent, experienced engineers. Therefore, a lot of time must be spent with the workers, dry lathes, milling machines, grinders, copper machining centers, etc.; then in the office to compile craftsmanship, estimate material consumption, and calculate quotas.
You must be familiar with the performance of various machine tools and the skill level of the workshop masters. In this way, after 2-3 years of practice, you can basically become a qualified craftsman. From my personal experience, I suggest that young college students who have just started to work should learn from the master workers with an humility. Once they can pass on decades of experience to you, you can avoid many detours. Because these experiences cannot be learned from books, the selection of craftsmanship is based on the comprehensive consideration of equipment capabilities and personnel technical capabilities. Without the support and trust of employees, it is impossible to become an excellent craftsman.
Through such a long time of study and accumulation, you should meet the following technical standards and requirements:
1) Familiar with the structure and process characteristics of drilling, milling, boring, grinding and planing machines,
2) Familiar with the properties of processed materials.
3) A solid basic knowledge of tool theory, master the conventional cutting parameters of the tool, etc.
4) Familiar with the company’s process specifications, guidelines and general requirements that can be achieved by various process processing, and the process route of conventional parts. Reasonable material consumption and working hours quota, etc.
5) Collect a certain amount of data on tools, machine tools, and mechanical standards. Particularly, you must be familiar with the tool system used in brass machining tools.
6) Familiar with the selection and maintenance of coolant.
7) Have a common sense understanding of related types of work. For example: casting, electrical processing, heat treatment, etc.
8) Have a good fixture foundation.
9) Understand the assembly requirements and use requirements of the processed parts.
10) Have a good foundation of measurement technology.
2. Proficient in the application of CNC programming and computer software.
I think this is easier. There are only dozens of programming instructions, and various systems are similar. It usually takes 1-2 months to be very familiar. The automatic programming software is a little more complicated, and you need to learn styling. But for people with good cad foundation, it is not difficult. In addition, if it is manual programming, the foundation of analytical geometry is also good! Scholars are most adaptable to the learning of this knowledge.
In practice, the criteria for a good procedure are:
1) Easy to understand and organized, everyone can understand it.
2) The fewer instructions in a block, the better, with the purpose of being simple, practical and reliable. From the perspective of programming, I think the commands are also G00 and G01, and the others are auxiliary commands, which are set to facilitate programming.
3) Easy to adjust. It is best not to change the program when the machining accuracy of the parts needs to be fine-tuned. For example, if the tool is worn out, if you want to adjust it, just change the length and radius in the tool offset table.
4) Convenient operation. The programming should be compiled according to the operating characteristics of the machine tool, which is conducive to observation, inspection, measurement, safety and so on. For example, if the same kind of parts and the same processing content are processed separately in a vertical machining center and a horizontal machining center, the procedures are definitely different. In mechanical processing, the simplest method is the best method. As long as you have practical experience, you will definitely agree with this sentence!
3. Able to operate CNC machine tools proficiently.
In this process, you must learn: system operation mode, fixture installation, part datum alignment, tool setting, zero offset setting, tool length compensation setting, radius compensation, loading and unloading of the tool and tool holder, and the cutting edge of the tool Grinding, measurement of parts (proficient in the use of vernier calipers, micrometer cards, dial indicators, dial indicators, inner diameter lever indicators), etc.
The ones that best reflect the level of operation are: horizontal machining centers and large gantry (moving beams, top beams) machining centers.
The practice of operation requires savvy! Sometimes there is an artistic conception of “a leisurely heart, but a good point is difficult to talk to you”! In the cnc turning china workshop, you should calm down and practice hard!
Generally speaking, the process from the processing of the first part to the qualified processing accuracy requires the CNC programming technician to complete it in person. You can’t operate the machine proficiently, you can’t pass this level.
4. Must have a good tooling and fixture foundation and measurement technology level.
I list the tooling fixture and measurement technology separately because it is as important as the accuracy of the machine tool for the quality of parts processing, and it is one of the signs that reflects the level of the craftsman.
The entire process system: the accuracy of the machine tool is guaranteed by the machine tool manufacturer, and the tools and cutting parameters are provided by the tool vendor. Generally speaking, there are no big problems. Only the tooling and fixture are specially designed by the technicians for specific parts. Most of the parts on CNC machine tools are There is a certain degree of difficulty, so unpredictable problems often occur. I have been engaged in CNC machine tool user parts cutting and debugging for more than 10 years, and I have never encountered a fixture that does not need to be rectified.
During the commissioning, the first part failed to be processed, and more than half of the reasons were caused by the unreasonable positioning of the fixture, the clamping pressure point, and the clamping force. The difficulty in analyzing the cause of the fixture is that it can only be qualitative but difficult to quantify. If there is no experience in fixture design and part clamping, the difficulty will be great.
In this study, it is recommended to consult the senior technicians who are doing precision jig boring machines. One of the basic skills of machining to accurately measure the level is to be able to use vernier calipers, micrometers, dial indicators, dial indicators, inner diameter lever gauges, calipers, etc. proficiently. Sometimes parts processing, three-coordinate measuring machine can not be counted on. Must be measured manually. Imagine that the quantity of parts is not accurate. Which leader or worker will trust you? It can take a long time to practice measurement techniques!
5. Familiar with CNC machine tools. Proficient in the maintenance of CNC machine tools.
The so-called familiarity with CNC machine tools should:
1) Familiar with cnc milling china electrical components and control principles. Can tell the name and function of each component in the electrical box, and understand the electrical schematic diagram. The alarm content can be found based on the electrical alarm number.
2) Understand the structure and transmission principle of the ball screw. Know which factors have a greater impact on the accuracy of the machine tool.
3) Understand the structure of the bearings at both ends of the screw rod of the machine tool and its influence on the accuracy of the machine tool.
4) Understand the lubrication system of the machine tool (bearings, main shafts, motion pairs, gearboxes, etc.), and be clear about the distribution of lubrication points. The brand of machine lubricating oil and the normal consumption of oil every week or month.
5) Understand the cooling system of the machine tool: cutting (water, air) cooling, spindle cooling, electric box cooling, etc.
6) Understand the main transmission structure of the machine tool, and the specific data characteristics between the speed and torque of each machine tool.
7) Understand the characteristics of the machine tool guide rail pair: Is it a linear rail or a sliding rail, and how rigid (carrying capacity) is?
8) Common operating faults can be eliminated (such as: exceeding limit, tool magazine tool number error, etc.)
9) Proficient in various precision (static and dynamic) indicators and detection methods of machine tools.
10) Familiar with the tool magazine mechanism and the principle of tool change.
For the above items, if you don’t have more than 3 years to exercise, I am afraid it is difficult to meet the requirements. And many companies do not yet have the conditions to learn. It is recommended to consult the master of the equipment maintenance department.
I won’t talk about the details of machine maintenance. Each company has its own experience and standards. The main point of machine maintenance is to “raise”, and you should pay attention to it in normal times (long-term records should be made):
1) Start every day and pay attention to whether the start load changes of each axis of the machine tool are normal. This is very important. Abnormal start load changes mean that the resistance of the motion pair or transmission pair has changed, and you must stop the machine for inspection. Otherwise, over time, it will cause great damage to the machine tool;
2) Pay attention to the normal consumption of lubricating oil. Too much or too little must be checked.
3) Clean the air-conditioning filter and vent filter of the electric box frequently. Once the integrated circuit board of the power module and the drive module inside the electric box is stained with dust containing iron powder, the machine will give an inexplicable alarm, and the repair will not be possible. Just wait to change the board!
6. Cultivate good habits and adapt to the characteristics of CNC machining.
(This one is my personal opinion, whether it is reasonable, everyone can discuss) The masters suitable for CNC machining should be humble, rigorous, calm, careful thinking, methodical and independent.
1) The processing of some large parts not only has a lot of processing content, but also has the conversion of space three-dimensional coordinates. The calculation of the processing trajectory is very complicated and difficult to determine. If the problem is not considered meticulously and comprehensively, and the calculation is not accurate, the program modification becomes more chaotic when debugging, and the probability of error is greater. “Think twice before acting” is the most appropriate here.
2) The part debugging process is a process of multi-person cooperation, including operators, inspectors, fixture design, fixture assembly personnel, etc. When problems arise, you should consult them more, do more experiments, and avoid making arbitrary conclusions. Don’t blame too much on employees who make mistakes, and have a “compassionate” mentality.
3) The work of the medical machining tool is controlled by instructions. When debugging, you must be very clear about the path of the machine tool before pressing the “Start” button. Be rigorous and meticulous, and never let the machine tool move first. Once the program is wrong or the compensation parameters are incorrect, or the wrong coordinate system is selected. From scrapped parts, to serious accidents. Those who are grumpy, clueless, and do not change after repeated instruction are not suitable for the operation of CNC machine tools.
Let me tell you a fact: It turns out that our company has more than a dozen user debugging and cutting technologists, all of whom are well-informed and experienced, but none of them has not broken the tool in any year.
4) When there is a problem during debugging and processing, please calm down, and don’t panic or misuse again. The psychological quality is better.
5) When parts are unqualified for many times during debugging, the analysis must be organized, and the responsibility must be based on basis. Some relevant departments will give various explanations for various reasons. At this time, you must have your own opinion and remember: it does not matter if you do one thing wrong, but you cannot choose the wrong way to do it.
6) A technician, due to environmental constraints, always has limitations in technical ability. Coupled with the rapid development of technology, there is always room for improvement. When the internal technology of the factory has been digested, we must keep our eyes open and keep up with the advanced processing technology at home and abroad to learn and digest. Be a good adviser to the boss in terms of technology.

Ts Machining
the authorTs Machining