Forum: cooking.stackexchange.com
Tags: <knives>
Title: How to clean a whetstone?
Question: I prefer a whetstone to a "steel" for knife sharpening. Over the years my whetstone has become loaded with steel particles from the knives. As it is basically 13 % chrome stainless steel it is not easy to dissolve. It is immune to nitric acid and hydrochloric is very slow , if at all . Any ideas for cleaning a whetstone ?

Answers:
sents: text: If this is an oilstone (which is considered old fashioned exactly because of these issues), an oft-mentioned ultima ratio remedy is boiling it in soapy water.
text: YMMV, this could destroy the stone.
text: If you know what exact type (eg arkansas)
text: your oilstone is, research instructions specific to that stone type.
text: If it is a waterstone, abrading the stone - with a flattening plate, diamond stone, another waterstone until unaffected material is brought to the surface is the recommended method.
answer_details: author: cooking.stackexchange.com/users/35312/rackandboneman
score: 5
sents: text: My uncle used a dry stiff wire brush to remove crud, then dipped the brush into a pail of sudsy water and scrub it again.
text: Then use a cloth with clean water (well wrung out), a dry up with a clean cloth, and a final dry wire brush on any remaining spots.
answer_details: author: cooking.stackexchange.com/users/63065/Annamaynot
score: 4
sents: text: I think the best way to clean a old whetstone with lots of buildup would be to rub it on a flattening plate, which also has the advantage of flattening your whetstone.
answer_details: author: cooking.stackexchange.com/users/43744/Netduke
score: 3
sents: text: On a whetstone for use with water you use a nagura stone.
text: There are natural and artificial nagura, cheap ones and expensive ones.
text: The nagura is harder than your whetstone.
text: You rub it on your whetstone in between sharpening your knife whenever you feel the surface of your whetstone is loaded (clogged) with particles.
text: It abrases the surface of your stone, thus cleaning its surface while also creating the slurry, the mix of water and whetstone particles needed for a less aggressive, more regular sharpening of a knife.
text: Here ’s a YouTube video of cleaning a stone and creating a slurry with a nagura.
answer_details: author: cooking.stackexchange.com/users/85246/Philipp
score: 3
sents: text: While Bar Keepers Friend is a great cleaner with many uses, it is NOT great enough to clean an ultra-fine whetstone.
text: I use three grades of whetstone surfaces between two stones to do my sharpening jobs:
text: Coarse, Fine, and Ultra-Fine.
text: Coarse and Fine are on a single bastard stone, and Ultra-fine is a smaller dedicated stone.
text: The cleaning problem is presented by the ultra-fine whetstone; it remains clogged by particulates and discolored by impurities, the colors of which range from the expected shades of grey to suspicious sticky brown.
text: Boiling with detergents did not help.
text: Lye (potassium hydroxide or sodium hydroxide) did.
text: Two caveats: Do NOT allow it ANYWHERE near aluminum (it acts as does acid), and use VINEGAR (acetic acid) to neutralize it.
text: Lye works greatly on lots of things, especially when it comes to deposits involving extremes of heat and time, but it should be used with great care.
text: The reasons why "excessive" bathing was generally regarded as unhealthy was understandable—considering people over a century ago were horribly ignorant regarding chemistry and physics.
text: (nobody thought to bathe with vinegar after applying lye soap)
answer_details: author: cooking.stackexchange.com/users/65603/William Kuns
score: 2

Summary of the answers:
You could boil an oilstone in soapy water, or scrub it with a dry stiff wire brush dipped in a pail of sudsy water. However, the recommended method would be to use a flattening plate, diamond stone, nagura stone or another waterstone to bring unaffected material to the surface. A flattening plate will also flatten your whetstone in the process.
How you clean a whetstone depends on the type of stone. If it is an oilstone, soapy water, scrubbing and rubbing are recommended. If, however, it is a waterstone an abrading stone or nagura stone  are the cleaning methods of choice.