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Wood Carving Gouge |
Edge Angle
Use the Projection Calculator to set the projection and USB distance from the grindstone. This calculator is web-based and does not require Excel.
A tree is our most intimate contact with nature.
George Nakashima
Remember to hone / strop the edge -- this is very important for carving tools!
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General Guidelines |
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Material |
α |
Notes |
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Hand work |
Mallet work |
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| Softer woods | 15° | 18° - 20° | For softer woods like bass or tupelo, this works well. |
| Medium woods | 17 ½° |
20° - 22 ½° |
For woods like maple |
| Harder woods | 20° | 23° - 25° | For harder woods like ash or oak, this works well. |
The Tormek SVD-186 Gouge Jig (or SVD-185) is recommended.
The Tormek SVS-38 Short Tool Jig or SVS-32 may be appropriate. It is used in a similar manner to the SVD-186 and the SVD-185.
You may need to use a standard, off-the-shelf collar to guide the sharpening process. Most hardware stores carry these, or you can order one such as part number 9414T9 (7/16 inch) or 57485K68 (10 mm) from McMaster-Carr. Note : You will probably need to replace the set screw with a longer one.
The Tormek MB-100 or MB-102 may be used with the SVD-186 (or SVD-185) or SVS-38 (or SVS-32) to provide adequate adjustment of the jig angle setting and not have the jig interfere with the grindstone. The side of the grindstone can assist with this. Using the SVD-186 (or SVD-185) is useful if the edge needs softened corners.
When sharpening, be very careful about the edge's shape. Also, be cautious about taking a decision to round the corners off too fast. It is easy to do, but often requires quite a bit of grinding and metal removal to re-establish a flat edge profile.
The diagrams below show the edge when viewed from above.
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A flat edge with crisp corners (i.e., a straight line when viewed from above) - Useful for operations like lettering. | |
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A slightly rounded edge - Useful for work such as sideways slicing. | |
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Softened corners - Useful for Hollowing and leaving no tool marks are best achieved using a tool which has its corners a bit "softened". |
Smooth inside surface |
Rounded cutting bevel |
The inside surfaces of bent and spoon gouges (shown in red to the upper picture to the left) need particular care. The surface should have a smooth, flowing shape to allow the removed wood a smooth transition away from the surface. If not, it can cause tears in the surface.
The bevel on the gouge needs to be convex when cutting into curved wood surfaces, and this bevel's radius needs to be smaller than the hole. Doing so reduces the bruising to the wood as the carver rotates the tool through the cut.
This is shown in the area marked red in the lower picture to the left.
Microbevel on inside surface
One school of thought is to put a secondary / micro-bevel on the inside of the gouge's curve. The thinking is that this allows the shape to be longer, more tapered, but not have too acute an edge angle as to be less usable on harder woods.
This approach also allows the tool to be held at a shallower angle (to the wood) which makes carving easier.
As shown to the right, this can increase the effective cutting angle by 2° - 5° quite easily, without having to regrind the larger surface.
Additional notes are also available on a different web page for Micro / Secondary Bevels.
Carving edges are typically not reground; only to reshape them, or repair a problem with the edge. More commonly, the edge is simply honed on the leather wheel.
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Ian recommends that the cutting edges be ground to 10° on both sides of the cutting edge, resulting in an α of 20°. The resulting edge looks rather like a knife. Pictures in the article explain this better.
This approach is quite different from others I've read, especially for gouges and V-tools.
