How To

A Guide to Waterstones: Sharpening Stone FAQs

18 Nov 2021

Waterstones are a popular type of sharpening stone that can cut fast and produce a very smooth finish when used with water. They also wear with use and need to be flattened frequently. Read on to learn how to flatten these stones and get other tips and recommendations for using and caring for your waterstones.

How Do You Flatten a Waterstone?

Waterstones dish fairly easily but can also be brought to flatness with considerably less work than benchstones. There are two methods you can use to flatten waterstones: using sandpaper or, as we recommend, a specially designed flattening stone.

To flatten with sandpaper, mount 100 grit waterproof sandpaper on a piece of flat glass and rub the stone across the surface of the wet sandpaper.

Flattening stones are oversized coarse, hard silicon carbide stones designed with a diagonal pattern or grooves molded on the surface to make flattening easier. These diagonal grooves enhance the flattening process by allowing the swarf to be removed from the stone’s surface during the sharpening process. To use them, soak both the flattening stone and the waterstone in water, then rub the surface of the waterstone with the flattening stone to wear away the high spots on the waterstone face.

Should I Store My Waterstones in Water or Dry?

Either storage method will work, but our recommendation depends on how often you use the waterstone.

If you sharpen frequently - every week or so - you may prefer to keep your stones soaking in water, so that they are always ready to go. This will save you the 30 minutes of soak time before sharpening. If you’re storing your stones in water, we recommend adding a few drops of bleach to the water to inhibit bacterial growth.

If you sharpen less often, we recommend storing your waterstones dry as mold could build up, and the water may freeze during the extended periods of time when your stones are not in use.

To learn more about our waterstone offering, browse our products. For more answers to your sharpening stone questions, check out our benchstone FAQs.