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Scraper Blade

 

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Edge Angle

The Scraper Blade's cutting edge is formed by one step on the grinder. The grinding action forms the hook.

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Sharpening the blade using the Tormek SVD-186


Whilst using this tool, you may need to hone often with a diamond file.

Crafts make us feel rooted, give us a sense of belonging and connect us with our history. Our ancestors used to create these crafts out of necessity, and now we do them for fun, to make money and to express ourselves.

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General Guidelines

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Sharp
ness

Comments

65°
6

The Tormek SVD-186 or SVD-185 is easily used for this activity. As shown in the picture above, you will use the shaft rather than the tool holder.

Reference the Tormek handbook, Water Cooled Sharpening of Edge Tools if you have any questions.

Notes & Comments

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High Speed Grinders

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.

Dr. Larrin Thomas noted in his book, Knife Engineering: Steel, Heat Treating, and Geometry (2025),

The lack of sparks or color changes is no guarantee that the edge was not overheated.

Therefore, sparks are not necessarily a sign that heat has or has not been generated in the steel. Color changes can occur from overheating of steel in grinding, but during grinding, the surface is being removed, and the affected volume can be relatively small. Therefore a color change is not always observed.

Microhardness measurements of edges sharpened with a belt sander show a drop in hardness at edge. This results from “over-tempering” the edge by heating it above its original tempering temperature.

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.)


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Example icon

Sharpness Scale

Sharpness scales (as shown in the grey icon to the left) are used to indicate the recommended sharpness for the blades noted above. You can click on any of the icons showing the sharpness scale and be redirected to the page describing this more. Lower numbers are duller; higher numbers sharper.

These are general recommendations; you will need to use your own judgment, based on the knive’s intended purpose.


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