Routing in Woodworking

Definition and Explanation of Manufacturing Technology
Milling is a machining process: A rotating, multi-edged tool removes material as the tool and workpiece move relative to each other. In woodworking, the tool sometimes moves across the workpiece—as with a hand-held router—and sometimes the workpiece moves across the stationary tool, as with the router table and a bench router.

Chamfering on the RUWI router table

Milling is a versatile machining process. In this article, you'll learn how milling works and what you need for it. We'll also show you the most important technical principles and methods used for milling wood.

Table of Contents

• Definition: Milling explained simply
• What types of milling are there in woodworking?
• Technical Principles of Milling
• Milling Tools for Wood Milling
• Materials Used for Milling
• Milling in Woodworking Professions
• Practical Application: What Can You Mill?
• Historical Background of Milling

Definition: Milling explained simply

Milling is a machining process that removes material and shapes it, allowing you to work with nearly all solid materials. When milling wood, you can get by with relatively simple machines—but that doesn’t mean a bench router is easy to operate. During milling, you remove material from a workpiece to create any desired contours, such as perimeter edges or slots, steps, pockets, or hole patterns. Even uneven or cracked surfaces can be planed smooth.

What types of milling are there in woodworking?

There are numerous types of milling, for example, by direction of cut, material, or the desired shape. A key point is always the question of climb milling or conventional milling.

Milling Processes Overview

When it comes to milling, we distinguish between manual and CNC processes:

• Manual routing: You move the workpiece or the router bit by hand. This can involve working with a hand router or guiding the workpiece on a stationary machine.
• CNC Milling: In this process, the workpiece is clamped into a machine and guided by an automated system.

For manual milling, you can also differentiate between:

• Freehand routing: Using a hand-held router, guided by a guide ring, copying sleeve, or guide rail. You do not work freehand on a bench router—there, the stop, guide ring, and arc stop provide the guidance.
• Jig Milling: You use a milling jig or template (for example, in face, form, or profile milling).

Milling Processes by Direction of Cut

Counter-feed milling: The cutting edge moves against the feed direction at the point of contact. The cutting force acts against your direction of thrust, the workpiece remains controllable, and you immediately feel it if anything changes. When feeding by hand, this is the direction of operation—not a recommendation, but a requirement.

Co-directional milling: The cutting force and feed direction are in the same direction, and the tool pulls the workpiece toward itself. This self-feed cannot be controlled during manual feeding—not even with practice. The article “Co-directional Milling” explains when and under what conditions co-directional milling is permissible.

3D unit on the RUWI router table with a rounding cutter

Technical Principles of Milling

To mill wood, you need a milling machine. In woodworking, this is often a router, which you can also convert into a router table a milling jig. Factors such as speed, feed rate, and cutter diameter are important.

Cutting Width

If you're milling through the material (for example, a slot), the cutter diameter determines the cutting width.

Feed Motion

The feed rate refers to how fast the tool and workpiece move relative to each other. Harder materials or larger milling cutter diameters require a lower feed rate.

Cutting Speed

The cutting speed is determined by the cutter diameter and rotational speed: The larger the cutter, the lower the rotational speed. If you're unsure, choose slower settings to avoid damage. Never exceed the maximum rotational speed indicated on the tool.

Milling Tools for Wood Milling

The cutter head is the most important part. There are hundreds of different designs and types, for example:

• Profile cutters
• Chamfering cutter
• Rounding cutter
• flush trim bit
• Groove cutters
• V-groove cutters
• Lettering cutters
• Finishing or roughing cutters
• Slotting cutters
• Rabbeting cutters
• Finger cutters
• Drill mills
• Router bits with replaceable inserts or cutting edges

Choose the right tool for each step to ensure clean results and to prevent damage to both the operator and the tool. On bench routers, only tools approved for manual feed may be used—identified by “MAN,” “HANDVORSCHUB,” or the BG-TEST certification mark.

Materials Used for Milling

Woodworking machines are designed for wood and certain plastics. Metal or mineral-based materials require specialized equipment. The following materials can generally be machined reliably on a wood router:

• Wood (solid wood, hardwood, softwood)
• Wood-based materials (MDF, plywood, particleboard)
• Plastics (depending on the machine and router bit)
• Rarely light metals (under specific conditions)

Milling in Woodworking Professions

Milling is one of the most important shaping processes in woodworking. You’ll find it in nearly all woodworking trades, such as:

• Joiners or cabinet makers
• Carpenters
• Toy makers
• Boat builders
• Instrument makers
• Stair builders
• Interior decorators

Routers are becoming increasingly important, especially in carpentry—for example, for creating precise tenons and mortises in beams. Whether you’re inlaying a design into a cabinet door or planning to work with a tree slice, a router covers a wide range of applications.

Practical Application: What Can You Mill?

Milling covers a wide range of applications in woodworking. Typical milling tasks include:

• Surfacing: Leveling surfaces, for example, smoothing rough wood or log slices.
• Dimension routing: Bring a workpiece to the desired angle.
• Profile routing or profiling: For example, chamfering or rounding edges, or creating decorative profiles.
• Texture routing: Routing hole patterns, pockets, or recesses on the surface.
• Groove milling: Cutting slots grooves, for example, for slot.

Especially when using a router attachment or a router table , you can achieve consistent results because the stop and support guide the tool, and the set height remains the same throughout the entire run.

Routing round stock with the router

Historical Background of Milling

Milling has a long tradition in woodworking. As shipbuilding and the furniture industry flourished, the tools continued to evolve. During the Industrial Revolution, milling processes as we know them today became established. Later, many of these techniques were adapted for use in metalworking. Today, milling is one of the most important methods of precision machining in mass production—and in the woodworking trade, it has become an indispensable part of the workshop.