8.4mm Valve Guide Knurling & Resizing arbors

The tool is designed to restore the valve guides by rolling the spiral groove on the inner surface of the sleeve. It lets by deformation of the material to reduce the internal diameter of the valve guide.

– material HSS
– HRC 62±1

Recovery (knurling) of the valve guide must be made from smaller diameter of tool with a subsequent increase until the valve guide stem stops, enters into the sleeve.

Cone working part prevents cracking of parts, but keep in mind that any material may to break down.

Knurling reduces resolution at the receiving 0.04-0.06 mm depending on the material.

Example: original size of the valve guide ø8,02 after rolling ø8,1 inner hole will be ø7,95-7,98, depending on the material.

After recovery (rolling) inner hole is calibrated by valve guide reamer.