The Oil on Your Stone

[Andrew Pitonyak]

The claims I have heard about different mineral oils is that the difference is often in how consistent the particle sizes are. I have seen it claimed (probably by Norton and I am too lazy to look it up, which makes me think it might have been something from like $75 years ago) that mineral oils will have different size particles and that Norton's has very uniform sizes and, unlike some, will NOT dry out in the stone.

I have seen the claim that the oil can dry in the stone and gum it up, but I have never met anyone who has claimed that it has happened to them. One advantage to Norton is that it is food safe, but I would think that you could easily clean a knife that had something like Kerosene on it. It was mentioned that you can get food grade mineral oil by the gallon very cheap on amazon. I have a gallon of that that I use especially when I know I will be using lots of it like sharpening an axe. With my Norton sharpening station, I do use the Norton mineral oil.

I have always been concerned with using actual baby oil with other additives just because I am worried about them drying in the stone (again, not that I have ever heard anyone ever say that it happened to them, but I did see it written in some material). I expect that if you sharpen often enough it will no be a problem. I have let some stones sitting in a zip lock bag with lots of oil on them and did not have a problem and I could not begin to tell you what mineral oil I used on them. These were Norton India and Crysolone stones that still work fine even if I leave them sitting for some years before I get back to them.

What a great tip about checking the viscosity, especially if the bottle is clear; had not thought of that.

Has anyone even heard of somebody having mineral oil gum up (usually claimed due to evaporation of something or other) in a stone? I have heard of people cleaning stones that had things gummed up in them but the claim was generally not about mineral oil being left but more that the stone had not been kept suitably clean. If it was an India or Crystolone type stone they are cheap enough I would just replace it. An Arkansas stone I might worry about.

[Scott Winners]

I have a Norton 3 stone system, an IM313. Used to belong to my grandpa. He used motor oil in it from about 1950 to 1980. I am confident motor oil additives are more sophisticated now than they were 50-80 years ago - but the stones that came with the unit were not gummed up. I was using 3 in 1 oil on the old motor oil soaked stones with no problems except for the dish in the stones.

Along with new stones, I bought two quarts of the Norton oil and am happy with it. The only downside to the Norton oil I could find online was the price, I didn't see anywhere on the internet anyone make any other complaint about the Norton oil on Norton stones. I figure if I am not happy with my sharpening results using the Norton oil on the Norton stones either my technique is bad or I am using the wrong tool for the job.

[Jim Koepke]

Has anyone even heard of somebody having mineral oil gum up (usually claimed due to evaporation of something or other) in a stone? I have heard of people cleaning stones that had things gummed up in them but the claim was generally not about mineral oil being left but more that the stone had not been kept suitably clean.

If there is much swarf in the oil on a stone it needs to be wiped off before putting the stone away. Mineral oil isn't a polymerizing or drying oil. If a stone is left uncovered with oil on it, it may get gummed up from dust over time.

There is nothing about baby oil being 'food grade' on the container. If it is put on a baby's hands or arms, it is going to get into the baby's mouth.

Mineral oil in the pharmacy section is labeled "lubricant/laxative." If you can take a couple table spoonfuls as a laxative, it better be safe if a little gets on your knives and cutting boards.

This reminds me of another form of mineral oil sold in retail establishments is cutting board oil. That may be more expensive than the more pedestrian mineral oils.

My knives are always washed thoroughly after they go to the shop for a sharpening. Though many feed stores carry gallon containers of mineral oil the price is often not better than buying from a grocery pharmacy section by the pint. The last time a MSDS (Material Safety Data Sheet) was requested the people at the store thought they had that information but couldn't find it. Since my mineral oil gets used on my cutting boards having something known to be safe for surfaces that come into contact with food is important.

Another thought about mineral oil sold in feed stores is it may be thickker than the mineral oil one finds on their grocer's shelf.

jtk

[James Pallas]

I’ve always used mineral oil. It seems to stay on the stone and not run off the edge. I was taught the oil is used to float the swarf and keep it out of the stone. The other thing I was taught is do not use paper towels. The stone will cut the paper and that will build up and clog the stone. Oil, lint free rag and blot not rub. Stones get oily and box gets oily but not messy. Best of all one kind of oil in the shop. Cutting oil, protectant oil, general oiling for tools and machines and for oneself if needed.
Jim

[Jim Koepke]

Best of all one kind of oil in the shop. Cutting oil, protectant oil, general oiling for tools and machines and for oneself if needed.

Hmm, my generation has always thought it best to stay away from sharp things when one is 'quite well oiled.'

jtk

[James Pallas]

Well said Jim😂

[Dennis Droege]

Here's a very late comment: I had a little business 35 years or so ago going around to cookware stores with my oilstones (Crystolon, India, Arkansas) in a bag, sharpening knives folks would bring in. At that time, I began to use mineral oil; bought it from farm supply stores by the gallon. As of this date, I'm about halfway down on my second gallon and have been very happy with it.