With the development of science and technology, the rise and maturity of the world’s advanced manufacturing technology, which have put forward higher requirements for CNC machining technology.
In the processing of molds, what aspects should we pay attention to? There are several things we can do.
1.Clamping of end milling cutter.
The end milling cutter in the CNC machining center mostly adopts the clamping method of spring clamp set, which is in the cantilever state when used. In the milling process, sometimes may appear gradually out from the end of the mill clip, or even completely dropped, resulting in the phenomenon of scrap workpiece, the reason is because of there is the oil film between the tool clip hole and mill shank, resulting in the lack of clamping force.
Milling cutters are usually coated with anti-rust oil, it should be cleaned with cleaning liquid first before clamped, then drying.
When the diameter of the milling tools is large, even if the handle and clip are very clean, the accident may happen, then should choose the handle with a cut notch and the corresponding side locking way.
Another problem that may occur after clamping is that the neutral milling cutter is broken at the end of the cutter clamp, the reason is generally because the tool clamp use time is too long, the end of the tool clamp has been worn into a cone, at this time should be replaced with a new tool clamp.
2. Vibration of end mill cutter.
When the occurrence of tool vibration, we should consider to reduce the cutting speed and feed speed, while if both have been reduced by 40%, there is still a large vibration, it should reduce the amount of cutting.
If resonance occurs in the machining system, it may be caused by over cutting speed, low feed speed, insufficient rigidity of the tool system, insufficient clamping force of the workpiece, and the shape or the clamping method of the workpiece, etc. Measures should be taken to adjust the cutting dosage, increase the rigidity of the tool system, improve the feeding speed and so on.
3. When milling the surface, the ball end mill cutting speed at the tip is very low, so it should be appropriately forward spindle speed and prevent cutting with the tip.
4. Prevent straight cutting.
There are two types of flat-bottomed cylindrical milling cutters, one is that the end face has a hole, and the end edge is not in the center. The other is that the end face no holes, and the end blades are connected and over the center. When milling a curved surface, the end mill with a hole cannot feed straight down like a drill, unless the process hole is drilled in advance. Otherwise, the milling cutter will be broken. If a holeless end knife can be used to feed straight down, but because the point of view of the blade is too small, the axial force is large, so it should be avoided as much as possible. The better way is to feed the tool diagonally downward, and then use the side edge to cut laterally after reaching a certain depth.
When milling the groove surface, the process hole can be pre-drilled for cutting. Although the effect of straight cutting with a ball end mill is better than that of a flat-bottomed end mill, this method of cutting is not used because the axial force is too large and affects the cutting effect.
5. In milling surface parts, if found that the part heat treatment is not good, there are cracks, arrangement is not uniform phenomenon, we should stop the processing in time.
6.It requires a long period when in the milling mold cavity more messy surface, therefore, before milling, we should check the machin, fixture,cutting tools, so as not to occur in the middle of the disease, affect the processing accuracy, and even form waste.
7. In the process of mold cavity milling, according to the roughness of the processing surface, the appropriate amount of cutting file should be controlled. As for the difficult parts of milling, if the roughness of the processing surface is poor, it should be appropriate to leave more allowance for the finishing file; As for the plane, rectangular groove and other simple processing parts, we should try to reduce the roughness of the processing surface, reduce the amount of filing, to prevent large areas of filing and affect the precision of cavity surface.
8. Rough milling should be based on the allowance given by the machined surface, the milling should be done layer by layer according to the contour surface, such kind of milling efficiency is high.
The purpose of semi-finishing milling is to mill out the steps of the workpiece, so the use of ball nose milling cutter for finishing process generally set aside 0.5mm, half finishing line and step spacing is larger than finishing.
All in all, above are some basic knowledge about the carbide end mill processing procedures, hope this article willhelp you to further understand the CNC tool. Any question, please feel free to contact Melody.