CNC Woodworking vs Metalworking: Machine Comparison Guide for 2026

When I bought my first CNC machine I was convinced I could have one machine that did everything well. I needed to cut aluminum parts for a project and also wanted to do wood signs for a side business. I chose a machine that split the difference. It was not rigid enough for good metal cuts and not fast enough for efficient wood carving. I ended up buying a second machine a year later and the first one sat unused.

The reality is that woodworking and metalworking place fundamentally different demands on a CNC machine. The machine design that excels at one is compromised for the other. Understanding the differences before you buy saves thousands of dollars and months of frustration.

This guide compares CNC routers designed for woodworking with CNC mills designed for metalworking across every important dimension.

Why the Same Machine Cannot Do Both Well

The conflict between wood and metal machining comes down to three variables: rigidity, speed, and chip management.

Wood requires high spindle speeds and fast feed rates. A typical wood routing operation runs at 15,000 to 20,000 RPM with feed rates of 200 to 600 inches per minute. The wood fibers shear easily so cutting forces are low. The machine needs to move fast and cover large areas.

Metal requires high rigidity and high torque at lower speeds. A typical steel milling operation runs at 2,000 to 6,000 RPM with feed rates of 20 to 80 inches per minute. The cutting forces are high. The machine needs to resist deflection and maintain positional accuracy under load.

A machine optimized for wood has a lightweight gantry that moves quickly. A machine optimized for metal has a heavy cast iron frame that absorbs vibration. These design goals are opposed. A heavy mill frame cannot move fast enough for efficient wood cutting. A lightweight router frame deflects too much for accurate metal cutting.

Chip management is the third conflict. Wood produces dust that must be vacuumed away. Metal produces chips and requires coolant. A machine designed for dust collection has open construction and vacuum ports. A machine designed for coolant has sealed ways and coolant containment. Using a mill for wood fills the coolant system with dust. Using a router for metal sprays coolant across open linear guides.

Quick Comparison Table

Specification	Woodworking (Router)	Metalworking (Mill)
Frame material	Aluminum extrusion, steel tube	Cast iron, welded steel
Typical weight	200-1,500 lbs	1,000-10,000+ lbs
Spindle speed	12,000-24,000 RPM	3,000-10,000 RPM
Spindle power	1.5-9 HP	3-40+ HP
Feed rate	200-1,000 IPM	20-300 IPM
Positional accuracy	±0.002-0.005 in	±0.0002-0.001 in
Work envelope	Large (4x8 ft common)	Small to medium
Cooling	Air (dust collection)	Flood coolant
Typical cost (entry)	$3,000-$15,000	$8,000-$30,000

Machine Construction and Rigidity

The frame of a CNC machine determines everything about its cutting capability. Woodworking CNC routers use aluminum extrusions or welded steel tube construction. The frame is designed to be lightweight so the gantry can move at high speeds with low inertia. A typical 4x8 foot router frame weighs 500 to 1,500 pounds.

Metalworking CNC mills use cast iron or heavily welded steel frames. The cast iron construction provides natural vibration damping. Vibrations from cutting are absorbed by the mass of the frame rather than transmitted to the cutting tool. A typical benchtop mill weighs 1,000 to 2,000 pounds and a full-size VMC weighs 8,000 to 15,000 pounds.

The rigidity difference affects every aspect of cutting quality. A router frame deflects under the cutting forces required for steel. The deflection causes chatter, poor surface finish, and dimensional inaccuracy. A mill frame is too heavy to move at the speeds required for efficient wood cutting.

Gantry design is the most visible difference. Routers use a moving gantry where the bridge travels over a stationary table. This allows large workpieces to remain stationary. Mills typically use a moving table where the workpiece travels under a stationary spindle. This provides better rigidity because the gantry does not need to move.

Some hybrid machines use a moving gantry design with heavier construction for cutting aluminum. These machines work for light metal cutting but cannot match the rigidity of a true mill for steel work.

Precision and Accuracy

CNC mills achieve significantly higher precision than routers. The rigid construction and precision ground ballscrews of a mill allow positional accuracy of ±0.0002 to ±0.001 inches. Mills also maintain this accuracy under load because the frame does not deflect.

CNC routers achieve positional accuracy of ±0.002 to ±0.005 inches. This is adequate for woodworking where material movement from humidity changes causes more variation than the machine’s positioning error. A wooden workpiece can move 0.010 inches across a 24 inch span with a 10 percent humidity change.

The precision difference matters most for parts that must fit together. A milled metal part can be held to tolerances that allow direct assembly without adjustment. A router-cut wood part typically requires sanding or fitting.

Lead screw type contributes to the accuracy difference. Mills use precision ground ballscrews with minimal backlash. Routers often use ACME lead screws or rolled ballscrews which have more backlash and lower positional accuracy. Some high-end routers use ground ballscrews but the frame rigidity remains the limiting factor.

Spindle Speed and Material Removal

The spindle is the second major differentiator between wood and metal machines. Woodworking spindles are optimized for high speed with moderate torque. A typical router spindle runs at 12,000 to 24,000 RPM with 2 to 5 HP. The high speed allows small diameter router bits to cut efficiently. A 1/4 inch bit at 18,000 RPM has a surface speed of 1,180 feet per minute which is ideal for wood.

Metalworking spindles are optimized for high torque at lower speeds. A typical mill spindle runs at 3,000 to 8,000 RPM with 3 to 10 HP. The lower speed allows higher torque which is needed for the heavier chip loads in metal cutting. A 1/2 inch end mill in steel at 4,000 RPM has a surface speed of 524 feet per minute which is within the optimal range for carbide tools.

Router spindles are typically air-cooled. The fan or cooling ribs on the spindle housing dissipate heat during operation. Air cooling is adequate for wood cutting because the cut generates less heat and the high spindle speed moves air across the housing.

Mill spindles use liquid cooling or rely on flood coolant to remove heat. The higher cutting forces in metal generate significant heat that air cooling cannot manage. Coolant flows through the cutting zone and carries heat away from both the tool and the workpiece.

A router spindle running at low RPM for metal cutting operates outside its optimal range. The cooling fan moves less air at lower speeds which can cause the spindle to overheat. A mill spindle running at high RPM for wood cutting may lack the speed for small router bits.

Feed Rates and Material Removal

Wood routers remove material at much higher rates than metal mills. A router cutting hardwood at 400 inches per minute with a 1/2 inch depth of cut removes 200 cubic inches of material per minute. A mill cutting steel at 40 inches per minute with a 0.100 inch depth of cut removes 4 cubic inches per minute.

The 50-to-1 ratio in material removal rates explains why router spindles run at high speeds. The fast material removal requires high RPM to maintain proper chip load per tooth. A router bit at 400 IPM with 18,000 RPM and two flutes has a chip load of 0.011 inches per tooth which is ideal for wood.

A mill cutting steel at 40 IPM with 4,000 RPM and four flutes has a chip load of 0.0025 inches per tooth. The smaller chip load is appropriate for metal because the material strength prevents thicker chips at reasonable cutting forces.

If you run a router bit at mill speeds, the material removal rate drops to the point where wood cutting becomes uneconomical. A sign that takes 10 minutes on a router would take 3 hours on a mill running at metalworking feed rates.

Wood routers remove material at much higher rates than metal mills. A router cutting hardwood at 400 inches per minute with a 1/2 inch depth of cut removes 200 cubic inches of material per minute. A mill cutting steel at 40 inches per minute with a 0.100 inch depth of cut removes 4 cubic inches per minute.

The 50-to-1 ratio in material removal rates explains why router spindles run at high speeds. The fast material removal requires high RPM to maintain proper chip load per tooth. A router bit at 400 IPM with 18,000 RPM and two flutes has a chip load of 0.011 inches per tooth which is ideal for wood.

A mill cutting steel at 40 IPM with 4,000 RPM and four flutes has a chip load of 0.0025 inches per tooth. The smaller chip load is appropriate for metal because the material strength prevents thicker chips at reasonable cutting forces.

If you run a router bit at mill speeds, the material removal rate drops to the point where wood cutting becomes uneconomical. A sign that takes 10 minutes on a router would take 3 hours on a mill running at metalworking feed rates.

Work Envelope

CNC routers have significantly larger work envelopes than mills at the same price point. A $5,000 router typically has a 2x3 foot or 4x4 foot cutting area. A $5,000 mill typically has a 12x6 inch or 18x12 inch cutting area.

The large work envelope of routers matches the needs of woodworking. Sheet goods come in 4x8 foot sizes. Kitchen cabinets, furniture parts, and signage are large. A router with a 4x8 foot table can process full sheets.

The small work envelope of mills matches the size of metal parts. Most machined metal parts fit within a 12 inch cube. Engine blocks, transmission cases, and machine components are compact relative to furniture.

Work envelope size also affects machine cost. A large work envelope requires a larger frame, longer linear guides, and larger ballscrews. These components scale nonlinearly with size. A 4x8 foot router with mill-level rigidity would cost more than a house.

Chip Management: Dust Collection vs Coolant

Woodworking produces fine dust that is hazardous to breathe and damaging to machine components. Wood dust contains silica and other particulates that cause respiratory problems with prolonged exposure. The dust also clogs linear guides and ball screws which increases wear and reduces accuracy.

CNC routers require dust collection systems that move 400 to 800 cubic feet of air per minute. The dust boot surrounds the cutting tool and captures chips and dust at the source. A shop vacuum or dust collector pulls the dust through a hose and into a collection bin or filter system.

Metalworking produces chips that are heavy and sharp. The chips are removed from the cutting zone by flood coolant which also lubricates the cut and removes heat. The coolant is filtered and recirculated through the machine.

Using a mill for woodworking introduces wood dust into the coolant system. The dust mixes with coolant to form a sludge that clogs filters and pumps. The dust also settles on electrical components and can cause short circuits.

Using a router for metalworking requires flood coolant which sprays across open linear guides and ball screws. The coolant washes away the lubrication on these components and causes rapid wear. The coolant also creates a mess that a router’s open construction cannot contain.

Tooling and Material Suitability

Woodworking CNC tools are router bits with carbide cutting edges. The bits have larger diameters and simpler geometries than end mills. Common types include straight bits, spiral bits, compression bits, V-bits, and ball nose bits. Router bits are designed for high-speed cutting of soft materials with chip loads of 0.005 to 0.020 inches per tooth.

Metalworking CNC tools are end mills made from carbide or HSS. End mills have more complex geometries with variable helix angles, chip breakers, and coatings. Common types include square end mills, ball nose end mills, corner radius end mills, and chamfer mills. End mills are designed for lower speeds with chip loads of 0.001 to 0.005 inches per tooth.

Tool holding also differs. Routers typically use ER collets for tool holding. Mills use BT, CAT, or R8 tool holders with ER collets, TG chucks, or hydraulic chucks. The tool holding on a mill must resist tool pullout under heavy cutting loads.

Materials Each Machine Can Cut

CNC routers excel at cutting wood, plywood, MDF, plastics, foams, and composites. They can cut aluminum with light passes but the material removal rate is low. Routers cannot effectively cut steel, stainless steel, titanium, or other ferrous metals.

CNC mills excel at cutting steel, stainless steel, aluminum, brass, copper, titanium, and cast iron. They can cut wood but the slow feed rates make it impractical for large parts. The lack of dust collection creates additional problems.

Aluminum is the overlap material that both machine types can cut. A router cuts aluminum with light passes using a single-flute or two-flute end mill at high speed. A mill cuts aluminum aggressively with multi-flute end mills at moderate speed. For occasional aluminum work, a router is adequate. For production aluminum work, a mill is required.

Cost Considerations

Entry-level CNC routers cost $3,000 to $8,000 for a machine with a 2x3 foot or 4x4 foot work envelope. Mid-range routers cost $8,000 to $20,000 with more rigid construction and better components. Industrial routers cost $30,000 and up.

Entry-level CNC mills start at $8,000 to $15,000 for a benchtop machine with a 12x6 inch work envelope. Full-size VMCs start at $30,000 and go up to $100,000 or more for production machines.

The total cost includes tooling, software, and accessories. Router tooling costs less because router bits are simpler and cheaper than end mills. CAM software for woodworking is less expensive. VCarve Pro costs $700 while Fusion 360 for metalwork costs $500 per year for the full manufacturing package.

Dust collection for a router adds $500 to $2,000. Coolant systems for a mill add $1,000 to $4,000. These costs should be included in the budget.

Total Setup Cost Comparison

Cost Category	Woodworking Router	Metalworking Mill
Entry machine	$3,000-$8,000	$8,000-$15,000
Tooling starter set	$200-$500	$500-$1,500
CAM software	$700-$2,000	$500-$2,000/yr
Dust/coolant system	$500-$2,000	$1,000-$4,000
Accessories	$300-$800	$500-$2,000
Total entry cost	$4,700-$13,300	$10,500-$24,500

Making the Right Choice

If you primarily work with wood and occasionally cut aluminum, buy a CNC router with a liquid-cooled spindle and a dust collection system. The liquid-cooled spindle handles aluminum cutting better than air-cooled. Accept that aluminum cutting will be slow and require light passes.

If you primarily work with metal, buy a CNC mill. The investment is higher but the machine will cut accurately and efficiently. Using a router for serious metal work leads to frustration and poor quality parts.

If you need both capabilities, buy both machines. A dedicated router for wood and a dedicated mill for metal costs less over time than trying to make one machine do both. The router handles large wood parts quickly. The mill handles precise metal parts accurately.

For more information on machine selection, see our [CNC Machine Types Guide](

G90 G54 G00 X0 Y0
G01 Z-0.1 F10
G01 X1.0 F20
M30

/posts/cnc-machine-types-guide/) and CNC Mill vs Router Guide. For buying advice, see our CNC Machine Buying Guide.