One of the basic concepts to understand in any milling operation is Cut Direction. It can be characterized by how the flutes of the cutting tool engage the stock material and form the chip that is removed during cutting. In many of MecSoft CAM’s 2½ & 3 Axis toolpath strategies you will see that Cut Direction is defined by selecting one of three options, Climb, Conventional or Mixed. Let’s take a look at the characteristics of each option.
Climb Milling

Conventional Milling

Mixed (Climb/Conventional) Milling
The Mixed option simply means that the CAM software uses a combination of the two milling directions within the same toolpath. This option is typically used in finishing cuts when very small amounts of material are being removed. A Mixed cut direction can reduce tool travel and the number of retracts and transfer motions, thus saving machining time.
Let’s Review:
- Consider each chip being removed as a wedge of workpiece material.
- The distance at the widest end of the chip is the Feed per Tooth.
Climb Milling (Down Cut):
- Less re-cutting of chips, higher quality surface finish.
- Less wear on the cutting tool (tool life is extended).
- More tool deflection encountered but less fixturing needed (cutting force is directed onto the workpiece).
- Machines and spindles need to be more rigid.
Conventional Milling (Up Cut):
- More re-cutting of chips, lower quality surface finish.
- More wear on the cutting tool (tool life is reduced).
- Less tool deflection encountered but more fixturing is needed (cutting force is directed away from the workpiece).
- Machines and spindles can be less rigid.
Mixed (Climb/Conventional) Milling:
- A combination of both methods is used within the same toolpath.
- Typically used in finishing toolpaths.
- Can reduce tool travel and machining time.