CNC drilling machines and CNC milling machines are important equipment in PCB processing. The equipment is expensive. The selection of CNC machine tools is very important not only for operation, process setting, and maintenance but also for the quality of products.

As a craftsman, considering pure technology and operation, the selection indicators of CNC machine tools generally start from the following aspects:

1. Rigidity and stability of machine table:

To make the machine tool have enough stability, and rigidity and avoid vibration, many manufacturers use marble as the material of the bed. Some Japanese manufacturers use steel as the bed. Because the deformation of steel at different temperatures is larger and more unstable than that of marble, the manufacturers will use compensation in the software to eliminate the accuracy loss caused by deformation. At present, most manufacturers use natural marble or artificial marble as the bed, and it is recommended to use the equipment of marble bed. Marble is maintained and scrubbed with detergent and water at ordinary times, and alcohol is not allowed. After wiping, dry it with a dry cloth and wait until the water evaporates completely before working.

2. Speed and stability of rotating shaft:

At present, there are two kinds of rotating shafts, one is the rolling bearing with a maximum speed of 80000 revolutions, and the other is the air bearing with a maximum speed of 120000 revolutions. If it is a milling machine, rolling bearings should be used. Because its longitudinal bearing is better than air bearings, its drill chuck is also the focus of the investigation scope of procurement. Some drill chuck is not easy to replace and maintenance is difficult, some drill chuck wears quickly become consumables and the replacement cost is very expensive, and some need daily maintenance to waste time. The presser foot of the rotating shaft is another, and its service life and design are unreasonable, which will also cause great trouble. For example, there is no seal between the shaft and the presser foot, resulting in a large power of the vacuum cleaner, resulting in a waste of funds for the purchase of the vacuum cleaner or a waste of power of the central vacuum cleaner, and may lead to poor chip removal in the hole of the circuit board.

3. Table movement accuracy and displacement repetition accuracy:

This is the most important point in the selection, and it can't be seen through pictures or ordinary operations. It can only be certified after purchase and testing. The current equipment can meet the design standard when it just leaves the factory. The key is whether the accuracy is very stable after one to two years of operation. Machine tools produced in Europe do well in this regard.

4. Feed rate of X, y, and Z axes:

At present, the feed rate generally uses a screw stepping motor with a speed of 25 meters per minute, while the new product has adopted a servo motor. A high feed speed can increase the production capacity by 20% - 40%. The speed of the Z axis is affected by the drill bit and the material being drilled. The feed rate does not have a great impact on production efficiency.

5. Table moving and fixing device:

In the past, many of the moving bearings of the tabletop were mainly based on guide rails, and there was also air floatation as the moving bearing of the tabletop. The air floatation table top is flexible and easy to maintain, so it is the first choice when purchasing. The device for fixing the circuit board on the table is generally a pneumatic chuck. The design of this chuck has an important impact on the replacement of the equipment in the future. It is generally required that it is not easy to wear, because this place is one of the most severely worn places in the equipment. Once worn, the replacement and debugging should be simple, including the debugging of the positioning accuracy of the machine tool (for the template used for the milling machine).

For more information about bantam pcb mill, cnc pcb milling machine, desktop pcb milling machine, plz feel free to contact us.