①It Should Be Able To Ensure The Accuracy And Precision Of The Workpiece Being Processed.

①It should be able to ensure the accuracy and precision of the workpiece being processed.

Anyone who has been doing machining for ten years knows that when the software crashes or an urgent order appears, if you can write a piece of G code in your hand, that is your real skill.

What exactly is the G code saying?

The meaning of G code, to put it bluntly, is to tell the tool where to go and how fast to go. The G01 command is used to draw a straight line, the G02 command is used to draw a clockwise arc, and the M03 command makes the spindle rotate forward. These basic instruction codes support 80% of milling operations.

Zhang, who has been running a lathe for 20 years, said that as an example of manual programming for CNC milling , 80% of the young people in the workshop now only know how to use UG software to generate tool motion trajectories. When the NC system encounters a power outage, they are completely unable to cope. Even a very simple step surface cannot be processed.

The first step of milling programming is to determine the coordinates

After getting the drawing, the first important thing to face is to determine the origin of the workpiece. Under normal circumstances, the position of this origin is usually set at the lower left corner, because the coordinate system is not completely fixed, so every value written later about the X-axis, Y-axis, and Z-axis is completely based on guesswork.

For example, for an aluminum block with a length of 100, a width of 60, and a height of 20, if we set the origin of the coordinate system at the geometric center of the top surface, then the Z-axis coordinate value of the bottom surface of the aluminum block should be minus 20. What needs to be reminded here is that it must not be reversed, because once such a reverse error occurs and leads to an operational error, the final result is that the entire workpiece will be scrapped.

If you choose the wrong feed speed, the tool will collapse.

When using a 2 mm end mill, the speed is set at 8,000 rpm. When processing aluminum parts, the feed parameter is written to F 600. This method is a basic and safe manual programming example for CNC milling . If stainless steel materials are processed, reducing the feed value to F 300 will make the entire process more stable.

A structural parts processing factory located in Dongguan paid more than 30,000 yuan in compensation last year just because of a tool collapse. After subsequent review and analysis, it was found that the entire reason for this situation was that the F value was set too high. Therefore, when performing the steps of opening narrow slots, it is better to slow down by half a step rather than blindly rush forward.

Don’t forget to write down tool replacement and coolant

Replace the T1 tool with a six-mm milling cutter, then start the M08 command to turn on the coolant supply, and then use the M09 command to turn off the coolant. In scenarios where the operation progresses quickly, operators often omit the above steps. Once omissions occur, the machining process will evolve into a dry cutting state, which will lead to the undesirable phenomenon of burrs on the cutter surface of the milling cutter.

The five-axis machining center in Nansha, Guangzhou has a monthly output of 30,000 pieces. In its maintenance records, there are very clear examples of manual programming of CNC milling . The tool life lasted two weeks longer than that of neighboring factories. The reason for this result is entirely because there are no missing records in the two program segments M08 and M09.

Manual milling of complex shapes is impossible

The Mandarin written language that people can now directly understand is expressed as follows: During the processing of products such as the middle frame of mobile phones and turbine blades, there are hundreds of points on the surface that need to be interpolated. If you rely on a hand milling machine and only rely on the feel of the hand to operate, it is completely impossible to complete the production task. When the G03 arc interpolation function is used to start running, the duration is often as long as four or five hours.

There is a mold factory over there in Suzhou Industrial Park, and the accounts are calculated clearly and clearly. They found that if the same injection mold cavity was used, manual milling would take a full week to complete, but using CNC machining technology, the finished product could be produced in just four hours.

More importantly, the dimensional fluctuations during this process can also be controlled within the wire level range, which is a very precise accuracy requirement.

It’s not too late to learn handwriting now

Nowadays, CNC has become popular, but the underlying logic of G code has not changed in a span of ten years. When you manually write it yourself, and then use the corresponding software to proofread and verify, your finger's control and feeling of the specific coordinate position will take on a completely different and unique state.

There is a 24-year-old Xiao Wang in Foshan. During last year, he achieved a leap in skills from just pressing the cycle start button to being able to independently write the entire milling program. As a result, he received an increase of 1,500 yuan during the salary assessment stage at the end of the year.

How many masters are there in your workshop who can still write G code by hand? Please discuss it in the message box and click like so that brothers who are still confused can also see it.