Technical Informations

What is the roughing and light knife in CNC machining?

What is the roughing and light knife in CNC Machining?

1, Roughing

Roughing generally refers to the first process of the part machining process, that is, starting from the blank.

Under the maximum load of the machine tool, in most cases, the largest possible knife should be used, and the maximum amount of feed should be fed as fast as possible. In the case of the same knife, the feed is inversely proportional to the amount of feed. Under normal circumstances, the load of the machine tool is not a problem. The principle of selecting the knife is mainly considered according to whether the two-dimensional angle of the product and the three-dimensional arc are too small. After selecting the knife, the length of the knife is determined. The principle is that the length of the knife is greater than the machining depth, and the large workpiece should consider whether the chuck has interference.

When roughing, in the case that the tool can withstand, the speed should be as slow as possible, and the feed should be as fast as possible, so that the tool wear is as small as possible, and the roughing efficiency is higher.

What is the roughing and light knife in CNC machining?(图1)

2, Light knife

The light knife is generally the last process of the part machining. The purpose of the light knife is to meet the processing requirements of satisfying the surface finish of the workpiece and preserving the appropriate margin.

Similarly, the light knife uses the largest possible knife, as fast as possible, because the fine knife takes a long time to use the most suitable cutting feed and feed. Under the same feed, the transverse feed is larger and faster, and the amount of curved feed is related to the finished finish. The size of the feed is related to the shape of the surface. Leave the smallest margin without hurting the surface. Use the largest knife, the fastest speed, and the appropriate feed.

Roughing and light knife are the first and last steps of machining, respectively. The choice of cutting amount is basically the opposite. It is very suitable to combine the two to understand memory.

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