What do the numbers on carving gouges mean?
The sweep number describes how curved the cutting edge is and the second number is its width — plus which handful actually earns a place in a first set.
- Difficulty
- beginner
- Time
- 10 min
- Read
- 3 min
Short answer
A carving gouge is described by two numbers, such as a 5/12. The first is the sweep — how curved the edge is, from 1 which is flat to 11 which is a deep U — and the second is the width of the edge in millimetres. V-tools are numbered separately, usually in the 12 to 16 range, and described by their angle.
The numbering looks arcane and is entirely logical once explained. It comes from an old Sheffield list and is used by most manufacturers, so a number 5 from one maker is close to a number 5 from another. What it lets you do is describe a curve precisely enough to buy the right tool without holding it.
Step by step
- Read the first number as the curvature of the edge.A 1 is flat — effectively a chisel. A 3 is a very shallow curve. A 5 is a moderate curve and the most generally useful. A 7 to 9 is a deep U. An 11 is a semicircle, often called a veiner. Higher numbers cut deeper for the same width.
- Read the second number as the width in millimetres.So a 5/12 is a moderate sweep, 12 mm wide across the edge. Some older tools are listed in inches and some makers use their own list, but the pattern is the same.
- Understand what the sweep actually controls.The sweep determines how deep a cut of a given width goes and how tight a curve the tool can follow. A shallow sweep smooths and shapes; a deep sweep hollows and outlines.
- Know the V-tool or parting tool separately.It cuts a V-shaped groove and is described by the angle between its wings — 45, 60 or 90 degrees — and its width. It is the tool for outlining and for cutting lines, and it is the hardest to sharpen.
- Know the specialist shapes.Fishtail gouges flare at the edge and reach into corners. Spoon or front-bent gouges curve up at the end for hollowing where a straight tool bottoms out. Back-bent gouges curve the other way for shaping mounds. Skews cut into acute corners.
- Buy a small number of good tools rather than a large set.Most sets contain several tools you will never use. A reasonable starting group is a shallow 3, a medium 5, a deep 8 or 9, a V-tool and a small skew or flat. Add the ones you find yourself wanting.
- Buy tools you can sharpen.A cheap gouge with soft steel will not hold an edge and a badly ground one takes hours to correct. Good carving tools arrive sharpenable and often nearly sharp; poor ones need substantial work before they cut at all.
Tips
- Palm gouges with short handles are used with one hand for small work; full-length handles are used with two hands or with a mallet. They are not interchangeable, and most people find they want palm tools for detail and full-size for anything bigger.
- Match the sweep to the curve you are cutting rather than trying to cut every curve with one tool. Sweeping a shallow gouge round a tight curve digs the corners in.
- The number stamped on the blade is worth reading before you put a tool away. Sorting an unlabelled roll of gouges by eye is slow.
Questions people ask
How many gouges do I actually need?
Far fewer than a set contains. Many carvers do most of their work with four or five. Buy a handful of good ones covering shallow, medium and deep sweeps plus a V-tool, and add specific shapes as specific jobs demand them.
Are palm gouges or full-size gouges better to start with?
It depends entirely on the scale you want to carve. Small relief work and chip carving want palm tools; anything struck with a mallet, or larger sculptural work, needs full-length handles.