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 ?
My uncle used a stuff wire brush to remove crud, then would dip the brush into a Paul of sudsy water and scrub it again. Then use a cloth with clean water well wrung out, finally a dry up with a clean cloth and a last wire brush on any spots.It
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.
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. YMMV, this could destroy the stone. If you know what exact type (eg arkansas) your oilstone is, research instructions specific to that stone type.
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.
I have a couple of problems with some of the "answers:" What if you don't KNOW what kind of stone you have, and how many people seek a specific kind of stone when buying them?
Certainly, hindsight being prefect sight, before buying a stone, one should know two things: 1) For what purpose is the stone to be tasked for? and 2) Which kind of stone is best suited to that task?
I've been using whetstones (VERY few steels) since…1974. I didn't do any research before any of my purchases. ONE factor determined my purchase selection: Did I have enough money?
Over the years I've managed to turn one knife into a toothpick with over-sharpening, and a couple of stones into variegated bas-relief sculptures through diligent use.
Another "guru" suggested Bar Keepers Friend. While it's a great cleaner with many uses, it is NOT great enough to clean an ultra-fine whetstone.
I use three grades of whetstone surfaces between two stones to do my sharpening jobs, Coarse, Fine, and Ultra-Fine. Coarse and Fine are on a single bastard stone, and Ultra=fine is a smaller dedicated stone.
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.
Boiling with detergents did not help. Lye (potassium hydroxide or sodium hydroxide) did. Two caveats: Do NOT allow it ANYWHERE near aluminum (it acts as does acid), and use VINEGAR (acetic acid) to neutralize it.
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. 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. (nobody thought to bathe with vinegar after applying lye soap)