Face milling

Definition and explanation of face milling in woodworking
Face milling is a technique that allows you to mill a wooden workpiece to a desired thickness. Precise angles and even surfaces are essential for beautiful, high-quality wood products. Raw wood from the sawmill is not directly suitable for decorative purposes; it is first dried and processed. Surface milling helps you to create a smooth and even surface.

In this article, you will find out how face milling differs from other techniques, which materials you can process with it and what other options a router offers you.

Flat-milling a wooden plank with a router

Table of contents

• Definition of
• Technical basics of face milling
  • Machine
  • Tool
  • Milling device
  • Work surface
• Which face milling cutters are used for face milling?
• What materials are used for face milling?
• Fields of application for face milling machines
  • Creating a flat surface
  • Face milling of unevenness and protrusions
  • Pockets, recesses and cut-outs in surfaces
  • Milling protruding edges flat
  • Face milling of tree slices or end grain cutting boards

Definition: What is face milling?

When surface planing, you remove material from the uneven surface of a solid workpiece to make it as smooth and flat as possible. It is a secondary process that follows immediately after cutting. Professional woodworkers typically use planers (jointer and thicknesser) to “plane” pieces of wood quickly and efficiently. However, their width is limited, and they can only process rectangular cross-sections. A surface planer is slower, but more versatile—it can process solid wood pieces or wood-based materials of almost any size, which is particularly useful for tree stumps or epoxy-filled wood panels.

Technical basics of face milling

A typical face milling machine consists of the following elements:

• Router
• Suitable interchangeable tool (face milling cutter)
• Work table with clamping devices
• Milling device with XY guide and plunge mechanism

Everything is available on the market, from simple hobbyist solutions (a collapsible router table with a hand-held router) to professional CNC-controlled machines. The router itself allows you to mount various cutters, such as indexable insert cutters. Thanks to the XY guide, you can move the machine along two axes and lock it in place at the desired positions.

Machine

A handheld router with a compatible guide system is essential. Make sure it has the right shank size (8, 10, 12 mm) and an adjustable speed range – excessively high speeds can cause burn marks in soft wood or quickly dull the tool.

Tool

In the router, you use cutters with the largest possible cutting width for face milling (typically 30 mm diameter). Indexable cutters are advantageous because you can rotate or replace the insert when it wears out. End mills with fixed cutting edges are also possible, but you should opt for low-wear carbide cutters.

Milling pockets, recesses, and cutouts in a surface

Milling device

It consists of rails (XY guide) on which a carriage with a plunge mechanism for the router runs. This allows you to move the machine precisely along both axes or lock one axis, for example, to "trim" a workpiece. Higher-quality systems are precision-engineered, can be disassembled, and can be stored in a space-saving manner.

SlabMatrix milling unit on the RUWI lifting table

Work surface

A sturdy, level workbench provides a stable base to ensure your workpiece rests securely. A sufficiently large perforated panel with the right clamping system is a good choice. Professional workbenches are often height-adjustable and come with a wide range of accessories (clamps, stops, etc.).

Flat-surface milling on a large joiner's table with trestles

Tip: The RUWI router table (a portable table router) combines the advantages of a sturdy worktable with the flexibility of a router.

Which face milling cutters are used for face milling?

In most cases, face milling cutters with an 8 mm shank and a diameter of around 30 mm are sufficient. Two or three cutting edges are common. Popular brands include Titmann and ENT. It's important that the cutter is robust enough to withstand the high stresses of face milling.

What materials are used for face milling?

Face milling is primarily used to level uneven surfaces, especially in solid wood. Wood-based materials such as particleboard, glued laminated timber, or plywood are usually already relatively smooth, so sanding is often sufficient. Nevertheless, you can also use face milling cutters to work on composite materials (wood and acrylic or epoxy resin). Just make sure there are no metal inclusions that could damage your router bit.

Flat-milling a tree pit made of solid wood

Fields of application for face milling machines

You can use a face milling machine in many scenarios:

• Producing a flat surface: Preparing boards, beams and blocks of solid wood into semi-finished products.
• Facing of uneven surfaces and protrusions: For example, planing uneven joints smooth after gluing.
• Pockets, recesses and cut-outs: Rows of holes, holders for glass plates or lamps can be milled into the surface.
• Routing protruding edges: Precisely format workpieces or add profiles.
• Face milling of tree slices or end grain cutting boards: End grain is difficult to plane, but can be smoothed well with a router.

You might also be interested in these milling processes:

If you'd like to learn about other milling techniques used in woodworking, check out our glossary for information on CNC milling, profile milling, slot milling, and more.