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Skew Chisel |
Edge angles
There are two Tormek jigs which can be used for sharpening the skew chisel.
SVS-50 with Closed Seat
SVD-110
The Tormek SVS-50 Multi-Jig (shown to the left) is the jig recommended in the Tormek manual.
Guidelines shown below are for use with the Tormek SVS-50 Multi Jig using the Closed Seat. The method for measuring the projection is shown below.
The Tormek SVD-110 Tool Rest also works quite well for shew chisels with flat sides (but not so well for those with curved sides). I found that this is my preferred approach now that I use the diamond grinding wheels.
If you pursue this approach with a diamond grinding wheel, I recommend you secure an additional universal support bar, and lock the height in place with a collar (at either the TTS-100 hole A or B). This makes resharpening the tool easy.
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To the absolutist in every craftsman, each imperfection is a failure; to the practitioner, obsession with perfection seems a perception for failure. Richard Sennett |
Honing a skew chisel before use is recommended.
There is a separate page in this handbook for Lacer-style Skew Chisels.
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General Guidelines |
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Edge Angle |
Skew Angle |
Profile |
Tormek SVS-50 |
Comments |
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| α |
Range |
γ |
Range |
JS |
P |
Hole |
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| 30° | 25° - 55° | 20° | 20° - 35° |
Straight Edge
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20° | 65 mm | B | For tight spots, detail work and finest finish. |
| 45° | 20° | 55 mm | B | For broad application. Considered easier to control than a 30° edge angle. | ||||
| 30° | 25° - 55° | n/a | n/a |
Radius Edge
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30° | 75 mm | B | For tight spots, detail work and finest finish. |
| 45° | 20° | 65 mm | B | For broad application. Considered easier to control than a 30° edge angle. | ||||
Setting the projection of the skew chisel on the SVS-50 using a TTS-100
This tool is one where reshaping the cutting surface can be onerous, and the Tormek BGM-100 Bench Grinding Mounting Set can be quite useful. When grinding on a high speed grinder, all the settings remain the same. (For more information on Shaping vs. Sharpening, see also, Grindstones and Other Sharpening Media.)
If grinding this on a high speed grinder or sander, be sure to manage the temperature so that the temper is not lost due to overheating.
| High Carbon Steel |
Temperature control is critical for high carbon steel. Tempering will be lost in the steel if heated until it is blue (~550°F / 300°C). Cool by dipping as needed in water. |
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High Speed Steel |
Cool by dipping as needed in water. |
| Steel with Carbide Insert |
DO NOT cool by dipping in water. This will cause the carbide to crack due to shocks.
It is also recommended to use a high grit wheel for sharpening carbide as lower grits can cause cracks in the edge leading to it being far more crack-ridden and brittle. (Lower grits can be used for shaping the edge -- see also, Grindstones and Other Sharpening Media - Quick Selection Guide.) |
A good source for the shape of a handle is The Wood Turner's Handy Book (1887), by Paul N Hasluck (see pg. 67, fig. 39).
Another source is the series of articles written by Aaron Keim, Making a New Chisel Handle for Tired Hands, (see details below).
Aaron noted, “Some of the most important tools in my shop are my chisels. Whether I am chopping, carving, or paring, they are in my hands all day. As I have gotten older and my arthritis/tendonitis has gotten worse, my needs have changed. In this blog, I will talk about my preferred chisel handle and show how I make a replacement handle to suit my needs.”
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