CNC Router vs. Mill – What is the Difference?

There are different types of CNC machines these days, and each is built with specific capabilities. Manual machines are no longer the only option for machining parts. Technology continues to advance machine design and abilities, and that’s led to Computerized Numerical Control (aka CNC) machines. This blog discusses two machine types: a CNC router vs. a CNC mill.

Both machines fall under the subtractive manufacturing category. They use a cutting tool to remove material from the workpiece and shape it into the desired design. Either equipment can machine a variety of materials like wood, plastics, and metals. They have their differences, so first we’ll cover the basics of a CNC router.

What is a CNC Router?

Let’s start by answering the question, “What does a CNC router do?”. This machine is designed to cut complex shapes from soft, thin materials. Common materials you’ll find a CNC router machining are foam, plastic, wood, and soft metals like aluminum. The applications are pretty diverse for this equipment. It’s often used in woodworking to create furniture. And it’s used for rapid prototyping and engraving as well. A router is especially useful for large pieces like signs or plates.

So, how does a CNC router work?

Let’s outline the main components of a CNC router. The frame supports the machine and contributes to its rigidity (this matters for precision and accuracy). A table is where the material is placed and secured by workholding. A spindle holds the cutting tool and performs the actual machining. And lastly, the control is the computer that instructs the router how and where to move.

The workpiece design and path of the cutting tools are pre-programmed using CAD and CAM software. The router’s control reads the program information and relays the XYZ coordinates the tool needs to move to (all of which were determined in the CAM program). The router cuts in three directions aka axes. Up and down is the Z-axis, left and right is the Y-axis, and forward and back is the X-axis.

What Is a CNC Milling Machine?

A CNC mill (aka CNC milling machine) also cuts complex shapes from materials to create a part. Depending on the type of mill, you can cut everything from brass and acrylic to titanium and steel. There are different machine sizes from desktop to industrial (which is also the case for routers). And there are different capabilities such as 3-axis, 4-axis, and 5-axis.

The basic components of a mill are the same as a router. You have your frame, machine table, spindle, and control. Just like the router, the part design and tool paths are created in CAD and CAM software programs and then read by the CNC control. Designs for CNC mills vary because there’s vertical machining centers vs horizontal machining centers. For this instance, we’ll use a 3-axis VMC to compare against the router. A VMC cuts in three directions: up and down is the Z-axis, left and right is the Y-axis, and forward and back is the X-axis.

So, what is a CNC milling machine used for? It’s tough to think of what you couldn’t make with this equipment. Our customers use DATRON 3-axis mills for mold making, electronic prototyping, cockpit control panels, embossing dies, telecom antennas, art projects, scientific instruments, optomechanical parts, and more.

CNC Router Vs. Mill

A CNC router has its uses as mentioned before but just like a CNC mill, these machines are not designed for every type of material or project. Hard metal machining is often left to other CNC machines (possibly a CNC mill). Depending on how complex the geometries are, a CNC mill is typically a better choice. That’s because a milling machine is more heavy-duty and rigid which allows the mill to cut with greater precision and accuracy. So, micromachining, precision machining and creating delicate and thin features would be a job for a CNC mill.

A router has a limited range of motion along the Z-axis compared to a mill, so it cannot make slots or deep holes. However, the large work surface lets the router reach high machine speeds. Plus, the footprint is not much bigger than the work area making it a compact machine. Whereas traditional CNC mills have much larger footprints since they need the weight to stay rigid.

If you’re wondering can CNC bits be used in a router, the answer is yes. While the router and mill are two different types of machines, end mills designed for a CNC mill are perfectly acceptable for router work. However, router bits wouldn’t be used on a CNC mill (this is because of tool design differences and the material the tool is designed to work with). DATRON’s line of carbide milling tools is frequently used on router machines.

The Best of Both Worlds

So, what about combining the benefits of a router and mill? That’s exactly what the engineers at DATRON thought. Thus, the DATRON milling machine was born. It has a gantry, like a router, so it can offer a larger work area but has a minimal machine footprint. The rigidity and precision issues typically encountered with a router were mitigated through extensive testing and engineering to find the perfect design. If you’re curious whether a DATRON is the right machine tool for your application, schedule a virtual demo with our application engineer team.