CNC milling
Definition and explanation of CNC milling in woodworking
Milling is a shaping, machining process and, alongside turning and sanding, is one of the most common methods used to manufacture wood products. CNC milling is used to produce free forms with repeatable, computer-controlled precision. A distinction is made between 2D and 3D CNC milling.
In this article, you will learn the most important information about CNC milling. You will also read interesting facts about machinable materials and the possible applications of CNC milling in woodworking.
Milling on a CNC milling machine
Table of contents
- Meaning: What is CNC milling?
- Technical basics of CNC milling in woodworking
- Variants of CNC milling in woodworking
- What materials are used for CNC wood milling?
- Fields of application for CNC wood milling machines
- Industries for CNC milling
- Which workpieces can be produced from wood with a CNC router?
- Requirements: Dimensions and Complexity
- Advantages: Milling wood with the CNC router
- Which machines are used for CNC wood milling?
- RUWI products for woodworking
Meaning: What is CNC milling?
CNC milling refers to the process of machining millable materials using a CNC machine. "CNC" stands for "Computerized Numerical Control." CNC milling is characterized by high efficiency and repeatable precision, as the milling process is controlled by a computer.
Technical basics of CNC milling in woodworking
When milling in wood technology, you process edges, create contours in panels or shape any geometries from blocks of wood. A CNC router carries out these processing steps with repeat accuracy, controlled by electronics and electromechanical feeds. This saves time and manpower.
- Edge finishing: A wooden panel or board is guided past a fixed router head, the shape of which determines the edge.
- Contour milling (2D): The cutter penetrates the panel at a specified depth and follows a pre-programmed contour.
- Free-form milling (3D): This is often performed using a robotic arm, which enables complex machining in three dimensions. The milling head is mounted on a spindle attached to the arm.
Variants of CNC milling in woodworking
Edge processing
Here you guide a board or strip past a stationary milling head. The edge shape results from the geometry of the cutter.
CNC face milling
As an alternative to dressing with planing machines, the milling cutter passes over the surface in overlapping paths. The workpiece is then turned over and milled again. This allows you to achieve a specific thickness or smooth out atypically wide parts.
Contour milling
With 2D coordinate guidance, the milling cutter plunges into the defined position and follows the desired contour. This allows external and internal contours to be milled precisely.
Free form milling
A robot arm with a milling head is often used for complex 3D designs. This process enables precise, repeatable results even with unusual free forms.
Tip: RUWI milling table for CNC woodworking
Chamfering, slotting, rounding, grinding, deburring, or face milling—a RUWI milling table is a semi-stationary system that enables precise milling operations on a sturdy worktable while offering you great flexibility.
What materials are used for CNC wood milling?
Generally, you will be working with soft, machinable materials:
- Various types of wood: hardwoods such as oak or beech, softwoods such as pine or spruce
- Wood-based materials such as MDF, particleboard, multiplex, or plywood
- Plastics (such as carbon fiber-reinforced plastic or glass fiber-reinforced plastic), provided they do not contain any metallic inclusions
Metals can only be machined to a limited extent on woodworking machines, as tool and machine wear would be too severe.
Fields of application for CNC wood milling machines
A CNC wood router is used to shape edges, panels or blocks. Important examples:
- Milling internal and external contours: 2D systems are inexpensive and precise.
- Nesting: All required components are machined out of a panel in a single pass.
- Drilling: Blind, slotted or through holes can be drilled automatically.
- Free-form milling: 3D machining of complex shapes, for example using a robotic arm.
Free-form milling with a flush cutter
Industries for CNC milling
- Carpenters and Joiners
- Furniture, window, door and timber component manufacturers
- Caravan and motorhome conversions
- Boat building
- Model and mold making
CNC milling is universal: you only need a few manual skills, while the machine produces high-precision individual or series parts.
Which workpieces can be produced from wood with a CNC router?
That depends on whether you're working with flat or block material. You process flat material, such as panels, on 2D milling machines; for "voluminous" components in all directions, you use 3D milling machines.
- Furniture fronts and carcass parts
- 3D wooden models
- Worktops, letters, engravings
- Wooden house doors, wooden toys, cupboards
- Stair treads, windows, fences
Finishing on the RUWI milling table after CNC machining
Requirements: Dimensions and Complexity
A 2D router machines panels but can also, to a limited extent, create deeper cuts such as blind holes. A 3D machine with up to five axes can handle complex components. The soft wood and relatively wide tolerances make this machine technology even more flexible.
Tool changer
Automated tool changing increases efficiency. The CNC control system automatically manages the replacement of milling cutters or drill bits. Common types include:
- Pick-up changer (few tools)
- Plate changer (medium number)
- Chain changer (large selection of tools)
Machine tables
The machine table makes a significant contribution to efficiency. Examples are
- Console tables with vacuum cups on sliding consoles
- Grid or matrix tables with foam rubber gaskets and vacuum
- Flat tables for 2D and 3D, often with clamping mechanisms
Advantages: Milling wood with the CNC router
- Repeatable, precise and low manpower requirements
- High level of automation
- Fast processing, no loss of time
- Safety: Operator is separated from the milling cutter
Once programmed, the CNC router repeats its movements an infinite number of times. With automated loading, it runs independently in optimum operation.
Which machines are used for CNC wood milling?
- CNC machining centers
- CNC portal milling
- Single and double-column bed-type milling machines
You will also find table routers, underfloor routers or stationary routers in the woodworking sector, although these are not always CNC-controlled.
RUWI products for woodworking
RUWI offers a variety of solutions for woodworking machinery. Whether you need to chamfer, groove, sand, or flush-trim edges, a RUWI router table is a versatile addition that combines stability and flexibility.
