CNC Machining Centres

1. Definition: CNC Machining Centres
2. Machining centres for completely automated processing
3. The development of machining centres
4. Areas of application for machining centres
5. Weakened joints
6. Large selection, high prices
7. Buying used machining centres
8. An overview of machining centre manufacturers

CNC machining centres play an important role in the used machinery market. Fully automated CNC milling machines set the standards in the production of complex workpieces. Because of their flexibility, precision and speed, machining centres are indispensable in the series production sector. Depending on the position of the main spindle, there is a distinction between a horizontal and a vertical machining centre. Machines with four or five axes are called universal machining centres. Different designs and the integration of different manufacturing processes provide further classification features. At Surplex you will find used CNC machining centres- also modern models with few operating hours!

A machining centre (MC for short) for metal is called a numerically controlled machine tool and is designed for processing workpieces with complex prismatic geometries using a single clamping process. Machining centres are fitted with tools for various machining processes, particularly milling and drilling. A typical feature of machining centres is the high level of automation, which includes both automatic tool changing and fully automated movement sequences.

• Processing of complex, prismatic geometries
• High level of automation
• Independent tool changing

Machining centres possess a main spindle which they automatically load from a tool magazine. It is possible to perform a numerically controlled movement between the main spindle and workpiece in a straight line on at least three CNC axes. Today, 5-axis CNC machines are used heavily in a range of locations. Rotary movement axes may also be included. CNC machining centres differ in terms of the position of the main spindle. They can come both in form of horizontal or vertical machining centres. If the machine tool can also alter the position of the main spindle, it is called a universal machining centre.

Differentiating machining centres

The key features used to differentiate machining centres are the number and type of CNC axes and tools in the magazine, the rotational speed range, cutting performance, dimensions of work routes and workpiece table and its load capacity, as well as the resolution capacity of the drives and entrance tolerance. Tool and chain magazines are used as tool storage in CNC machining centres. Star- and drum-shaped magazines are used depending on the position of the tools and it is possible for the feed direction to be parallel and perpendicular to the magazine axis. To reduce non-productive times, CNC machining centres use simple changers and double changers for modifying the tool, which can simultaneously remove a tool from the magazine and main spindle. The non-productive times for loading, unloading and clamping the workpieces can be reduced by means of pallet systems. This involves clamping the workpieces on pallets outside the work area, which are then transported independently by the machining centre. This largely enables workpieces to be changed parallel to processing procedures.

The history of machining centres is closely related to the invention of numerical machine tool controls (NC) and computerised numerical controls (CNC), as well as the development of motor spindles as autonomous components. Numerical controls enable workpieces to be machined automatically. Motor spindles fitted with a direct drive enable precise control of spindle movement even at high speeds. With its integrated tool magazine, a CNC machining centre can combine several types of machine tools, such as drilling machines and milling machines and even lathes within one structure.

Due to a high level of automation, machining centres are suitable for both large series production, small- and mid-sized series, as well as the manufacture of individual pieces. Their high processing speed is particularly important in serial production and explains their widespread use in large and small companies, ranging from car manufacturers to small-scale carpentry operations. However, acquiring a machining centre can be major financial challenge for many companies, which is why many firms involved in industrial production find purchasing used machining centres to be a sensible alternative. Second-hand machines> are often just as capable at performing as new models, but it is the comparatively low cost which makes all the difference.

A 3-axis or 5-axis machining centre can mill three-dimensional curves and radii into a workpiece. The high number of movable axes, however, inevitably affect the rigidity of the machine. A 5-axis machining centre is therefore comparatively sensitive to high feed rates or very resistant material. A 5-axis machining centre is prone to wear on all moving parts and these need to be regularly inspected. As such, a 5-axis CNC machining centre may look very appealing externally, but the internal condition could be in such a bad state of repair that repairs would not be economically viable. But this does not mean that the risks of buying a used 5-axis machine cannot be avoided.

CNC machining centres are high-tech pieces of kit. The highly precise coordination of all the axes while taking into consideration tool wear and material properties requires high-quality components as well as high-performance controls. The good news is that the controls do not wear out. A used CNC machining centre is just as capable as a brand new one, which is why even second-hand machining centres can be quite an investment and require a large amount of capital.

A CNC machining centre for metalworking is a central piece of kit in industrial operations. These high-performance, efficient and precise machines guarantee that any shape and form can be manufactured. Prototype construction, reworking cast iron parts or series parts made from solid material - a good CNC machining centre enables production to achieve new levels of performance. The weakpoints described make buying a CNC machining centre a matter of trust. This is why second-hand machinery traders who solely deal in approved and transportable CNC machining centres are the ideal places to acquire a used CNC machining centre. Comprehensively tested and thoroughly cleaned, with updated software (if requested) and all damaged or worn components replaced, a CNC machining centre bought from a second-hand dealer can be just as good as a brand new machine. The price difference alone between a new 5-axis CNC machine and a used machining centre is reason enough to consider taking the second-hand route.

Surplex offers a large range of high-quality machining centres: 3-axis, 4-axis and 5-axis machining centres. When possible, our used machining centres are professionally uninstalled, thoroughly inspected and maintained as required, which makes opting for a second-hand machine an easy decision. Surplex also offers comprehensive services for used 5-axis CNC machining centres in addition to their sales activities. Consultation, transportation, installation and upgrading can be performed by Surplex or one of our dependable partners.

So, you would like to buy a CNC machining centre? Surplex regularly has a wide range of high-quality, 5-axis CNC machines for sale, as well as other versions. It is worth opting for manufacturers who have been known for reliability and quality for a good number of years. Renowned companies include AXA, BECK, CHIRON, DECKEL, HERMLE, HECKERT, HAAS, HELLER, OKUMA and YEONG CHIN MACHINERY TAIWAN.

Our numerous industrial auctions regularly feature CNC machining centres for sale (with a range of axes) at attractive prices. If you cannot find the right used machine for your needs, simply try looking again another day. Alternatively, contact Surplex Customer Care and a member of the team will be glad to help.