Sharpening Parting Tools

To sharpen a parting tool or V-gouge, first check the profile. As they come from the manufacturer, many parting tools are ground with the nose slightly ahead of the ears. Because of this, the nose cuts the wood and begins to lift the chip before the ears have a chance to cut the sides of the groove. It makes more sense to let the ears lead the nose so the tool cuts the sides of the groove first, then cleans out the bottom.

When grinding the bevels, treat the tool as if it were two skew chisels joined at the sides. Each bevel must be ground to precisely the same angle, and you must remove the same amount of stock from both. After grinding the bevels, grind the nose (the point of the V) to the same angle as the bevels. This removes the small protruding hook that forms there.

SHARPENING A PARTING TOOL

1- It’s difficult to sharpen the bevels of a parting tool and arrive at the correct side profile, with the ears leading the nose. Instead, grind the profile first by feeding the nose of the tool into a sharpening machine. This flattens and dulls the cutting edges, but you can use these flat edges as a guide to maintain the desired profile.

2-After grinding the profile, sharpen the bevels. If you’re using a sharpening machine, make a guide block with angled sides and clamp it to the tool rest. As you work, constantly check the flattened cutting edges. As the flats grow thinner, the inside and outside surfaces must remain parallel. Stop immediately when both flattened edges disappear. When this happens, the cutting edges are ground to a keen point, the bevels are equal, and the ears lead the nose.

3- As you sharpen, the nose of the V-tool will develop a slight protrusion or hook. Remove the hook by grinding the point of the V (where the bevels join) to the same angle as the bevels. Be careful not to grind too much; remove just enough metal to eliminate the hook.