Accurately Round Chain Sharpening Wheels
The Grinding Wheel Radius Check Tool has four slots sized to fit Chain Grinding Wheels of 1/8", 3/16", 1/4" and 5/16" thicknesses.
To round a chain grinding wheel, use a Dressing Stick on the wheel while it is spinning to shape the edge until it matches the slot on the Radius Check Tool. Of course, turn off the wheel and allow it to stop moving before sliding the Radius Check Tool over it to check the fit.
Made of industrial poly-carbonate for years of use.