I swear by Bar Keeper's Friend cleanser. I do a 3 stage cleaning on all my sharpening stones and it works great. First I usually soak my stones in either a soluable machining oil solution or a solution made with TSP ( Tri-Sodium Phosphate). After soaking them overnight I then clean the stones with either Comet or Ajax. After cleaning the stones with one of those type of abrasive cleansers I then do a final stage of cleaning them with Bar Keeper's Friend cleanser.
I know that sounds like a lot of work but believe me when I'm done with them they are like Factory New and they cut & abrade very well after that type of cleaning,.
I've tried the eraser method and I will admit that it does remove a substantial amount of the metal filings embedded in the stone. But to have your stones honing and abrading like new I"ve never found a method that works better than the one I've described. Now I do usually wait till my stones are really plugged up bad before I go through all that trouble. Or I wait till I've got at least 12 of them needing cleaning. All I can say is that it works great for me.
I know that sounds like a lot of work but believe me when I'm done with them they are like Factory New and they cut & abrade very well after that type of cleaning,.
I've tried the eraser method and I will admit that it does remove a substantial amount of the metal filings embedded in the stone. But to have your stones honing and abrading like new I"ve never found a method that works better than the one I've described. Now I do usually wait till my stones are really plugged up bad before I go through all that trouble. Or I wait till I've got at least 12 of them needing cleaning. All I can say is that it works great for me.