Used Vertical Machining Centers
Horizontal CNC Machines for High Volume Machining
A Horizontal Machining Center (HMC) operates with its spindle in a horizontal position instead of a vertical position like a VMC. Many horizontal mills have built-in rotary tables that allow milling at various angles. Because of the configuration of the horizontal mill, they often have arbor-mounted cutters, sometimes called side and face mills that can cut a much wider swath enabling rapid material removal rates.
Both horizontal and vertical CNC machining centers can make many of the same parts. 99% of the time, new shops start with vertical machining centers and add horizontal CNC machines later. Often machinists ask the question Which is better for my application? A horizontal or vertical CNC machining center? Below are some factors to consider.
One shop owner noted that a part which took 48 minutes to make (with 9 different operations) on a vertical machine only took 22 minutes on a horizontal machining center. There were only 2 operations on the HMC which made a big difference! One horizontal milling machine can be as productive as three vertical milling machines.
Differences between Horizontal and Vertical Machining Centers
The horizontal machining center uses better chip evacuation methods when compared to vertical mills, which means less re-cutting and longer tool life. The surface finish from a horizontal mill machine is often better too. These machines are very sturdy and built to withstand vibrations, so the work environment is quieter, and the machine tends to last longer.
Many HMC owners believe that the higher initial investment in a horizontal CNC is well-worth it, since parts are less costly coming off the machine. Horizontal machining centers of various sizes, types, and ages fit different use cases.
Benefits of Horizontal Machining Centers as Compared to Vertical Machining Centers
- Higher production rate
- Quieter running
- Better surface finishes
- Better chip management (chips fall away)
- Better spindle utilization (more efficient)
- Fewer operators (but they need to be well-trained)
- Pallet change options available for automated loading/unloading
Disadvantages of Horizontal Machining Centers as Compared to Vertical Machining Centers
- Relatively large size
- More expensive
- Not as useful for milling large diameter short workpieces
- More challenging to train operators on programming
- Heavier and louder than vertical machining centers