Eliminating Milling Cutters for Mold Roughing

Vibration-absorbing tools (sometimes referred to as "silent tools") have been used in cutting applications for many years. When the mold processing shop needs to process a deep and narrow mold cavity, it often uses this tool to eliminate vibration problems caused by the slenderness of the tool.

Most die shops use silent cutters for finishing to obtain a smooth die surface that requires little or no secondary trimming. However, some processing workshops may not realize that they can also apply mute tools to rough machining, so as to obtain greater benefits.

Silent cutters (especially vibration dampening joints) enable the die shop to perform roughing at faster cutting speeds and feed rates, and can use larger depths of cut, usually to achieve similar overall steel cutter length tools Cut 3 times deep.

In addition, today's vibration dampening joints can be used with longer tool lengths than standard extended tools and can be used for a wider range of workpiece types and machining of workpiece materials – including stainless steel and titanium alloys.

The tool makes a noise when it vibrates. This is also the reason why the “quiet tool” gets its name. The vibration-damping joint uses its internal passive vibration-damping system to counteract the vibration of the tool. The vibration amplitude of this system is different from the amplitude of the vibration generated at the tool cutting edge.

The vibration relief joint is the interface between the machine tool spindle and the tool bit. The vibration relief joints and tools can be integrated to integrate the tool into the joint; it can also be designed as a tool system with the tool mounted at the end of the joint and replaceable.

A cavity is machined in the front part of the vibration-damping joint, into which a vibration-damping block is inserted. The anti-vibration block is a cylindrical heavy metal block suspended in the damping oil in the chamber. Both ends of these absorber blocks are provided with rubber seals, which in turn are connected to springs mounted on the edges of the chamber.

When standard tools start cutting, they begin to vibrate with a specific amplitude, and the shop usually eliminates the vibration by reducing the cutting speed and feedrate. On the other hand, when these vibrations are transmitted to the vibration absorbing mechanism of the vibration damping joint, the vibration absorbing block starts to vibrate up and down with the opposite amplitude. This movement occurs within a few milliseconds and cancels out with the tool's amplitude, completely eliminating any negative effects of vibration on the workpiece surface.

The damping mechanism in the silent tool adopts a passive vibration elimination system, which can counteract the vibration of the tool and thus control the vibration. This anti-vibration mechanism is different from the active anti-vibration system. The active anti-vibration system requires the introduction of external mechanical (or electrical) force/vibration to counteract the cutting force/vibration generated by the tool. Therefore, the system does not belong to the internal system and includes some type of external device.

Machine shops that do not use vibration-damping joints must set the tool to the length required for machining. However, in order to obtain a good surface finish, these knives have to be machined with incredibly small cutting parameters, which greatly extends the finishing cycle time and machining cycle time of the entire workpiece.

Machine shops that have used or plan to use vibration-damping joints should pay attention to the compatibility of vibration-damping joints and tools. Since the vibration-relief joints designed by professional tool manufacturers are usually used with the tools they produce, when the machining shop mixes and matches joints and tools, the joints and tools of the same manufacturer are most likely to be used to obtain the best cutting. performance.

In addition to mold milling, vibration dampening joints can also be used for turning, boring and drilling of bores. Like milling cutters, these tools work with overhangs that exceed the limit lengths of the overall steel shank and solid carbide shank. Because various types of back-end and front-end connectors are available, these tools are very easy to use and flexible.

Vibration reduction connector maintenance points

In about 95% of cases, the vibration relief joint only fails when the tool is damaged, otherwise the vibration relief joint can be used for many years. In fact, many anti-vibration systems made in the 1980s are still in use today. In order to ensure the best performance of the silent tool / vibration relief joint, the tool manufacturer provides the following six maintenance points:

(1) If the damping oil in the vibration-damping joint becomes too viscous due to long-term storage or transportation at a low temperature, gently tap the shaft of the joint with a rubber hammer.

(2) To maintain the best performance, carefully clean all fittings at least once a year and add lubricant. Lubricate the screws if necessary.

(3) Replace worn or worn screws and washers promptly.

(4) When assembling, make sure that the connector is properly tightened.

(5) Always check the reliability of the tool clamped by the vibration relief joint.

(6) Always use a torque wrench to correct the tightening force of the screws.