Manual Hole Lapping

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The flexible hone is an abrasive tool composed of small balls impregnated of silicon carbide. It is used in rotation and at low rpm.

The result they get is like a polished or lapped surface.
Another characteristic flex hones offer is to improve holes bumpy texture.

Flex hones are used in cylinders, hydraulic elements, aluminum injection parts, automotive, aeronautics, precision parts, weaponry, etc...