Aligning Grindstones When Attaching Them

When attaching a grindstone to the Tormek, there is some play between the hole in the grindstone and the machine's shaft onto which it is installed. The picture to the right shows that in a bit of a an exaggerated manner.

Once the retaining nut is installed, this alignment remains fixed during the rotation; the stone does not slip up and down.

Here you can note that, even though the grindstone has a diameter of 250mm (radius = 125mm), there is not a full 125mm to each side. This will result in the grindstone seeming to be out of alignment when running. You will see the surface go up and down.

As a good sharpener, you will of course true the surface of the stone to get it flat and even. The picture to the left shows an area in light purple that would be removed during this process.

This results in a stone which has an equal distance from the spindle shaft's center of rotation to all surfaces around the grindstone's edge.

But notice how the hole in the grindstone is not centered around the spindle shaft. This is not a problem as long as the stone is re-attached to the machine in the same orientation (in this case, with the grindstone's label at the 12:00 position).

If the grindstone is installed with the label at any other position, you will end up with a situation like shown to the right. This will result in a surface that goes up and down even worse than before!

This is a graphic depiction that is meant to help explain the concept, and all images were exaggerated; however I hope you see the value of re-attaching your grindstones the same way each time.

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Remember : The goal of sharpening is to produce sharp tools, and these tools can injure you if mishandled. Safety measures should be followed to protect yourself and those in your shop. Be sure to read and follow all instructions from the manufacturer, and and utilize proper safety equipment. Never consume alcohol or anything that could impair your judgement before sharpening tools, or using sharp tools. Comments can be sent via eMail to me at