cleaning those sharpening stones


Aug 30, 2002
I bought a Gatco sharpening rig 2 years ago. Sharpened dozens of knives to shaving sharp (raise a burr on each side, gradually remove it, etc.). Life was good!

Then, bought a Sharpmaker. Although I still used the Gatco to raise the burr on each side, I found the Sharpmaker quicker for the finish work. Life was even better!

Then, I got busy at work, etc. and didn't sharpen anything for months, until a couple weeks ago. It took me over an hour to raise just one side of the burr :rolleyes: , and by the time I was done with that 4" folder, I decided I must have lost my interest in sharpening, or something.

Tonight, I decided to try again. I tried using an older stone with the Gatco rig (one that was almost worn out; the course stone). It removed metal like no tomorrow! I had a burr within minutes. So, I wondered, what gives?

It turned out that the old stone was, indeed, rougher! The newer one was as smooth as a baby's behind (well, ;) by comparison). I thought I had effectively scrubbed out the metal debris from the stones, but I guess not. I just spent 20 mins with a Brillo pad, then rinsing/scrubbing with my forefinger on the stones. I think the "smooth" stones are now rougher, but...

After all that babble, does anyone have suggestions as to an effective (and, uh, quicker) way to to get those sharpening stones clean of debris -- so they'll actully sharpen in my lifetime?

I've boiled it in a solution of TSP [trisodiumphosphate] , that is good for getting out old and oxidized oil. One stone had so much buildup of old oil I thought it was dished but on cleaning it was actually flat !
I suggest hot water and abrasive sink cleanser on a terry cloth rag or a Scotch Brite pad. Another way is hot water and sink cleanser of a tooth brush. The detergent in the cleanser loosens built up waxy compounds and the abrasive digs them out. I have also had good luck using an abrasive stainless steal cleanser, either one for pans made by Revere or one made for stainless sinks called Bartender's Friend. Some cleansers work better than others.

Honing stones depend on breaking down their surface to expose fresh grit in order maintain maximum honing rates. Honing dry does not break down the surface as fast as honing with water or oil. Sometimes I hone with cleanser and water to try and refresh a smoothed-out hone. Sometimes I try water and 400 grit Wet-or-Dry sand paper to refresh a hone.
on a fine stone, you could also try an eraser, especially the harder ones like the white Pentel plastic eraser.
I tried erasers and soap/hot water on my Sharpmaker stones, and they did esentially nothing. What worked perfectly for me was NEVR-DULL metal polish. Go figure.
James Muehlner said:
I tried erasers and soap/hot water on my Sharpmaker stones, and they did esentially nothing. What worked perfectly for me was NEVR-DULL metal polish. Go figure.

Ah, I was using it on a Lansky Blue Sapphire polishing stone and a small Japanese waterstone slip... didn't remove all the color but did get rid of the glaze. Might not work for hard ceramics, though rubbing two flat ceramic stones together might (as in flattening water stones).

Haven't tried the metal polish trick, though many of these contain fine abrasive, as does kitchen cleanser like Comet (a little Comet on a wet Scotchbright pad was what I used back when I had a ceramic stick sharpener), which leads me to think that some toothpastes might also work (some of them work great for polishing silver too)
On cermaic I use a eraser made by smiths for cleaning ceramic rods and stones. On natural and man made stones I soak them in hot water and dish soap overnight and use a nylon brush. With the man made ones though, they will only come "so" clean. Ive never known one to completely be free of all debris. It seems to be the nature of the porous material.
On my Arkansas stones, I put them in a tub of soapy water and pop 'em in the microwave for a minute or two . Make sure it's a scrap container though, the oil and metallic crud that will come out will make it one anyway! For Japanese waterstones , a block and 400 wet-or-dry wakes them right up.

I find using those rubber/emery rust erasers works wonders on my ceramic stones.
I have used comet with a rag. Works great. I have read about guys putting them in the dishwasher, they say it works great. Never had the nerve to try it though.