Stresses in milling – what to watch out for
When we mill plates with large dimensions – slender material withsignificant length or width, and small relative thickness, we encounter various problems related to material deformation during processing. This is related to the stresses that are already present in the material itself, as well as those that arise during material waste processing.
Thus, when designing the machining process, we must bear in mind that, for example, holes should be made at the beginning before the deformed material begins to bend, while some less important processing elements can be performed later.
Fastening the material
A well-designed clamping of the material on the machine table or chuck is also necessary, because during processing it may slip out of the holders and fall out of the vice, or simply start bending too much. It will result in the production of elements not meeting their assumptions at best. Unfortunately this also pose serious safety issue.
Another difficulty that we encounter are vibrations that often occur in systems. When the component is large and thin, and the tool being processed causes the material to vibrate, the material resonates. Unfortunately it can lead to the material moving in the holder or even releasing the hold.
In extreme cases, the material may tear or the tool such as a cutter or drill may be damaged.
Excessive vibration increases the risk that the surface of finished material may not be satisfactory. To sum up both vibrations and deformation of the material affect the dimensional accuracy of the elements that we finally obtain.
Often in such situations we have to find a compromise between the quality of workmanship and the speed of processing.