Our stock of machine tools for sale : CNC tool grinding machine

A CNC tool grinding machine is a very specific form of CNC grinder dedicated to sharpening cutting tools. CNC grinding is a major advance in industrial machining that combines precision, automation and flexibility.

Micrometric precision and repeatability

Thanks to digital control, a CNC sharpener can achieve tolerances of less than 5 microns, guaranteeing perfect regularity of sharpening. This precision is essential in sectors such as aeronautics, the automotive industry and the manufacture of medical implants, where the quality of the cutting edges has a direct influence on the performance of the tools and the finish of the machined parts.

Automation and reduction of human error

CNC grinding machines operate using specialised software such as NUMROTO, Quinto or Helitronic Tool Studio, enabling programming and execution of identical grinding cycles. This automation brings numerous advantages, limiting human error, reducing waste and optimising the use of grinding wheels. In addition, the automatic sequence of operations without constant operator intervention improves the productivity and profitability of the workshops.

Optimisation of tool life

Precise sharpening extends the life of cutting tools by maintaining an optimal cutting angle. This reduces premature wear and avoids frequent replacement. For tools made of ultra-hard materials such as tungsten carbide, polycrystalline diamond (PCD) and cubic boron nitride (CBN), regular sharpening ensures a better cutting edge and prolonged performance.

Reduction of operating costs

CNC sharpening limits the purchase of new tools and avoids production interruptions due to blunt or broken tools. In addition, automated sharpening reduces the need for constant human intervention, resulting in lower labour costs and better use of resources.

Adaptability to a wide range of tools and materials

CNC grinding machines are compatible with different tool materials and shapes, whether milling cutters, drills, saw blades or reamers. They can sharpen tools made of high-speed steel (HSS), tungsten carbide or even PCD and CBN, used in high-performance applications. This flexibility makes it possible to meet the various constraints of cutting-edge industries.

CNC grinding is based on a high-precision automated process using controlled abrasion techniques. Using an abrasive wheel, the machine removes material in the form of very small chips to refine the cutting edges.

A CNC tool grinding machine is equipped with several axes that allow the tool to be sharpened to be positioned precisely in relation to the abrasive wheels. These wheels, often made of diamond or cubic boron nitride (CBN), perform the grinding at different angles to restore the cutting edge and the geometry of the tool. The key stages of the process include:

Loading and fixing the tool

The tool to be sharpened (drill, milling cutter, saw blade) is positioned and held on a rotating chuck or a specific support. Some machines, such as the Walter Helitronic Power 400, have an integrated automatic loader, optimising mass production.

Sharpening programming and simulation

The operator defines the sharpening cycle using CAD/CAM software such as NUMROTO, Quinto or Helitronic Tool Studio. The machine generates an optimised grinding wheel path based on the geometry of the tool and the required specifications. A 3D simulation allows errors to be anticipated and parameters to be adjusted before the actual execution.

Axis movements and dynamic adjustment

Modern CNC tool grinding machines are equipped with 5 to 9 interpolated axes, enabling precise tool positioning and multifaceted sharpening. For example, a Schneeberger Norma NGC combines linear axes (X, Y, Z) with rotary axes (A, C) to orient the tool at different angles. Absolute encoders and laser sensors ensure real-time correction of positioning deviations.

Controlled grinding and abrasion

The sharpening process is based on a diamond or cubic boron nitride (CBN) grinding wheel, rotating at speeds of up to 10,000 to 15,000 rpm depending on the hardness of the tool material. A controlled pressure is applied to minimise material removal and prevent thermal alteration of the tool. Some machines, such as the Vollmer VGrind 360S, use a dual spindle system, allowing simultaneous sharpening on several sides.

Dimensional control and automatic correction

High-end CNC tool grinding machines incorporate optical sensors and probes to measure the tool during the grinding process. The Walter Helitronic Vision is equipped with a Laser Contour Check system, which monitors the surface condition and automatically adjusts the grinding parameters if necessary.

Finishing and cooling

To prevent the tools from overheating, a high-pressure cooling system using oil or aqueous emulsion is used. Some machines, such as the Schneeberger Sirius NGS, combine directional cooling and advanced filtration to guarantee a clean cut and a longer service life for the grinding wheels.

CNC tool grinding machines are used in a wide range of industries, contributing to the performance and optimisation of machining processes.

Aeronautics

In aeronautics, precision is essential to guarantee the reliability of components for aircraft engines and structures. CNC tool grinding machines are used to manufacture and maintain the cutting tools used to machine parts made of light alloys, titanium and high-performance composites. The precise sharpening of drills, milling cutters and specific tools optimises the service life of the tools and ensures a clean cut without altering the material.

• Sharpening of carbide milling cutters for aeronautics: a Vollmer VGrind 360S is used to resharpen hemispherical milling cutters used for machining high-strength composite materials (e.g. carbon-titanium).

Automotive

The automotive industry requires cutting tools capable of producing high-precision mechanical parts, such as cam shafts, engine blocks and transmissions. CNC tool grinding machines ensure optimal sharpening of the milling cutters and reamers used for machining engine components, guaranteeing very strict tolerances and an impeccable surface finish.

• Jig grinding of solid carbide drills for the automotive industry: a Schneeberger Norma NGC machine sharpens the cutting edges of carbide drills used to drill aluminium engine blocks.

Medical

In the medical sector, CNC tool grinding machines are used for the manufacture of surgical instruments, implants and prostheses where precision is essential. Cutting tools for machining titanium, ceramics and biomedical alloys must be perfectly sharpened to ensure a clean cut and limit heating during machining. A CNC tool grinding machine makes it possible to obtain sharp edges that guarantee the quality and safety of medical devices.

• Grinding of medical cutting tools: the Walter Helitronic Micro is designed for the machining of dental surgery micro-tools, where precision is essential for clean cutting of bone tissue.

Manufacture of cutting tools

One of the main areas of application for CNC tool grinding machines is the production and re-sharpening of cutting tools used in various industries. These machines are capable of manufacturing carbide and HSS (high-speed steel) cutters with complex geometries adapted to specific needs. They also make it possible to recondition used tools, thus offering an economical and ecological alternative to buying new tools while maintaining their optimal performance.

Although CNC tool grinding machines are essential equipment for precision machining, their acquisition cost can be a major obstacle for many companies. The second-hand market is therefore an economical and strategic alternative, providing access to high-performance machines while optimising investments.

Opting for a second-hand CNC tool grinding machine has several advantages:

• Reduced costs: a second-hand machine can cost up to 60% less than a new model.
• More stable resale value: unlike new machines, which depreciate rapidly as soon as they are put into service, a second-hand CNC tool grinding machine retains its purchase value better.
• Immediate availability: unlike new machines, which require manufacturing and delivery times, a used machine can be purchased and put into production without delay.
• Proven reliability and consistent performance: a used CNC tool grinding machine that has been maintained and checked will immediately operate at full capacity, without the risk of manufacturing defects, unlike a new machine that requires a break-in period.
• Access to recognised brands: the second-hand market offers machines from reputable manufacturers such as VOLLMER, WALTER and SCHNEEBERGER, guaranteeing high-performance and reliable technology.

The purchase of a second-hand CNC tool grinding machine should be made through a qualified dealer capable of guaranteeing the quality and reliability of the equipment. However, this requires a thorough evaluation including:

• General condition: check the mechanical structure, the axes of movement, the integrity of the components and the absence of excessive play.
• Maintenance history: a well-maintained machine is often a good indicator of reliability. 
• Live testing: observing the machine in operation allows you to assess the precision of movement and the condition of the spindles and grinding wheels.

At Kraffter Machine Tools, the refurbishment of grinding machines involves a rigorous process of overhaul, verification, restoration and repair, guaranteeing that it works properly and performs as well as a new model.

The refurbishment stages

• Initial diagnosis: in-depth inspection of the machine and identification of components requiring repair.
• Complete overhaul of the machine: covering mechanical, hydraulic, pneumatic and electrical aspects.
• Cleaning and replacement of wearing parts: replacement of ball screws, linear guides, axis drives and other critical components.
• Modernisation of controls: updating of software and replacement of obsolete electronic components to improve the precision and user-friendliness of the machine.
• Calibration and validation: geometric verification and tolerance adjustment to guarantee optimal sharpening in accordance with the manufacturer's specifications.

Each machine is supplied with a geometric inspection report, guaranteeing that its performance complies with the manufacturer's original specifications. In addition, on request, we provide a complete service covering the logistics, including customs formalities, transport and handling of your equipment.

If you have a machine tool for sale, such as a CNC tool grinding machine that you no longer use, reselling it to a reconditioning specialist allows you to recover capital while promoting a sustainable approach.

• Accurate and transparent estimate: complete technical evaluation for resale at the right price.
• Quick and secure trade-in: turnkey solution including collection and transport of the machine.
• Commitment to the environment: participate in the circular economy by giving industrial equipment a second life.

At Kraffter Machine Tools, we offer comprehensive expertise in the purchase, sale and reconditioning of second-hand machine tools. We work with recognised brands such as Schneeberger, Walter, Anca, Isog and Vollmer to guarantee our customers high-performance, reliable machines. Whether you want to purchase a second-hand CNC tool grinding machine or resell your equipment, we will support you with a personalised service and solutions tailored to your needs.