4-Axis CNC Machining
Better-Mold have total three 4-Axis CNC Milling Machine and three 5-Axis CNC machining machine can do 4-Axis Machining job service .
This adds a rotation about the X-axis, called the A-axis. The spindle has 3 linear axes of movement (X-Y-Z), like in 3-axis machining, plus the A-axis occurs by rotation of the workpiece. There are a few different arrangements for 4 axis machines, but typically they are of the ‘vertical machining’ type, where the spindle rotates about the Z axis. The workpiece is mounted in the X-axis and can rotate with the fixture in the A-axis. For a single fixture setup, 4 sides of the part can be machined.
4-axis machining can be used as a more economically viable way of machining parts theoretically possible on a 3-axis machine. As an example, for a part we recently machined we found that using a 3-axis machine would have required two unique fixtures . By utilising the A-axis capability of 4-axis machining, only one fixture. This also eliminated the need for fixture change-overs, reducing costs even further. Eliminating the risk of human error meant we machined the part to a high quality with no need for expensive Quality Assurance investigations. Removing the need to change fixtures has the additional benefit that tighter tolerances can be held between features on different sides of the part. Loss of accuracy due to fixturing and re-setup has been removed.
There are two types of 4-axis CNC machining: indexing and continuous.
Index 4-axis CNC machining is when the 4th axis (A-axis) rotates whilst the machine is not cutting material. Once the correct rotation is selected, a brake is applied and the machine resumes cutting.
In continuous 4-axis machining, the machine can cut material at the same time as the A-axis rotation, simultaneously. This allows complex arcs to be machined, such as the profile of cam lobes, and helixes.
4-axis machining gives us the ability to machine angled features, otherwise not possible with a 3-axis machine. Bear in mind that 4-axis machining allows a single axis of rotation per fixture setup, so all angled features must be angled about the same axes, or additional fixtures put in place.