Think of a cube
3-axis will only allow you to machine features viewed from the TOP face
holes can only be drilled along Z axis
4-axis on a vertical will allow you to machine TOP, FRONT, BACK and BOTTOM. A horizontal can do FRONT, LEFT, RIGHT, BACK ( TOP cannot be done on a horizontal )
and depending on the 4th axis configuration - everything in between these views ( depending on your set-up ie 3-jaw chuck, vice, tombstone and so on )
5-axis allows you to tilt that 4th axis for access to 2 more faces to machine
There is usually one face that cannot be presented to the tool, this face can be inside a vice, on a fixture, stuck to a table ( it depends on the part, but it has to be held somehow )
There is tooling available that can be used to to get to non-presented faces on the 3 & 4 axes using an "aggregate head" ( right angle head is a simpler form of the tool), aggregate heads can be angle adjusted-but not by CNC code, it is set-up prior to the job starting ) |