① Clamping of milling cutters: most of the milling cutters used in machining centers are in the form of spring clamps, which are in a cantilever state during use. In the process of milling, the milling cutter may gradually fall out of the tool holder, causing the tool to fall off, and finally the workpiece is scrapped. The reason for this is generally due to the outer diameter of the milling cutter holder and the tool holder. There is a layer of oil film between the inner holes of the clamp, which is caused by insufficient clamping force. When the milling cutter is shipped from the factory, the anti-rust oil is usually applied. If the cutting oil is not water-soluble, this oil will cause a layer of misty oil film attached to the inner hole of the tool holder. In this case, the tool holder If there is a layer of oil film with the tool, it will be difficult for the tool holder to clamp the tool holder, which will cause the milling tool being processed to loosen and fall off. Therefore, before the milling cutter is used for clamping, the shank of the milling cutter and the inner hole of the tool holder should be cleaned with cleaning fluid, and then the cutter should be clamped after drying. However, when the diameter of the milling cutter is large, even if the tool holder and the tool holder are cleaned very clean, there may still be a tool drop accident. At this time, a tool holder with a flattened notch and a corresponding side lock should be used. Tight form. Another problem that may occur after the milling cutter is clamped is that the tool holder port is broken when the milling cutter is being processed. In general, it is because the tool holder has been used for a long time, which causes the tool holder port to be broken. It is caused by abrasion into a cone. The correct way is to replace the tool holder with a new one.
② Vibration of the milling cutter: There will be some tiny gaps between the milling cutter and the tool holder. These gaps will cause the tool to vibrate during the machining process. Vibration will cause the uneven cutting amount of the circumferential edge of the milling cutter, resulting in an increase in the cutting and spreading amount than the set value, which will seriously affect the machining accuracy and the tool life. But when the groove width is too small, the tool vibration can be controlled, and the required groove width can be obtained by increasing the cutting and expanding amount. However, in this type of case, the maximum amplitude of the milling cutter should be controlled below 0.02mm, otherwise Cutting will not proceed stably. In theory, the smaller the vibration of the milling cutter during normal processing, the better. But when tool vibration occurs, the first thing to consider is to reduce the cutting speed and feed rate. If both have been reduced to 40%, the tool does still have a large vibration, then consider reducing the amount of tooling. If there is a resonance phenomenon in the machined parts, the reason may be that the cutting speed is too high, the feed speed is too small, the tool rigidity is not enough, the workpiece clamping force is insufficient, and the workpiece shape or the workpiece clamping is not tight enough, etc., it should be connected at this time. Adjust the cutting amount, adjust the feed rate and so on.
