Thread: Glaze on kitchen hones

Hey all, long time no post. I got real busy with a job & fell out of the habit. Didn't even have time for my straight razor, let alone the internet. But I'm back. Anyway, this one is about the stones I use in the kitchen: silicon carbide, and fairly coarse Arkansas stones. I use them with a flow of water flooding over them, yet after a while, they seem to get a glaze and they stop cutting. The surface of the stone looks shiny when you look at it from an angle. I can lap the glaze off with wet sandpaper on a tile, but it's a lot of work, esp. with silicon carbide stones. Anybody know how to prevent the glaze forming in the first place? I presume the glaze is bits of abrasive clogging the stone. I use a kneaded eraser to remove the gray steel residue from the Arkansas stone, but the glaze does not come off by erasure, only lapping.

Thx,
-Johnny

Hey Johnny-

Your best bet, IMO, is to clean the stone before each use. Think of it as lapping-light, just a few swirls with a DMT 220 or 325 or a good rubbing with a coarser stone. This is why Naniwa supplies a "cleaning stone" with each Chosera. Used as you would use a slurry stone, they are hard 600 grit stones that serve to clean and flatten. You could also experiment with using dish soap or a commercial honing fluid to help suspend the steel & stone particles and allow them to wash away from the stones. OTOH, it's an old trick to allow some glaze to develop on purpose, effectively making the stone finer. Old timers called it "breaking in" a hone.

rs,
Tack

The metal that you are removing & small particles of the silicon carbide are filling the pours of the cutting layer beneath it. The silicon carbide stone is probably already impregnated at the factory with a lubricant; this collects the waste even faster.
As Tack stated, use a liquid dish detergent, Simple Green with a toothbrush, or one of the green scour pads to scrub the stone under water. This flushes out the pore of the stone. You can even use petroleum products such as WD-40. I've even seen gasoline used; out in the field, on silicon carbide stones to flush the pores , then rinse well with water. The WD-40 will sink under the grime & float it to the top, to be rinsed away.

Your lapping is just cutting away more layers of good grit(silicon carbide).

I'm not sure if it's because of the swarf. Every hard stone gets like that, over time. The "new" man made ones don't, but for the rest, I think, that's the true cutting power of the stone.
I don't know about the coarse Arkansas, but for the 1-5$ coarse SiC stones, I have seen it dozens of times. And, I was getting annoyed too.
What happens is, the stone comes from the factory with a coarse surface. You can feel it with your hand. This happens on every stone when it comes from the factory, that's why we lap them, and whenever someone has a problem with his new 4/8 norton, we ask them "have you lapped it yet?".
But for those coarse ones, it's a good thing, because they cut faster with that type of surface. And, after a while, they loose it, and cut as they suppose to cut.
And, if you would like to try this, buy a new one of those, lap them with 200-500 grit sandpaper or diamond plate, under running water, to be sure that it's not about particles clogging the surface. After some lapping, try the stone, and you will see that it cuts as the one you use for your knives, i.e. slowly.
It also happens because the stone is so hard, the particles of silicon carbide do not go away when the steel passes above, only lose their "teeth". And you end up with flat particles without any cutting power whatsoever, until a new one comes up, that can cut.
And, lastly, the hardness of the stone is a double edged knife . If the stone is too soft, a coarse stone scratches the steel so deep, it needs additional time on a finer stone to remove all those deep lines. That's why people are paying 50$ for a coarse Chocera, Shapton or Suehiro. Those big companies know how to make great quality stones without most of the bad qualities of the cheap ones.

I would give a slurry/cleaning stone a try. The Naniwa one costs around 6 euros in here and that should refresh the surface a little, as well as create a bit of slurry that increases the cutting power.

Ah, I think Vasilis is on the money. This is not swarf, because it can't be cleaned. It's the tiny little rocks of the abrasive losing their teeth. So I either have to lap the stone periodically (be it with sandpaper or a slurry stone) or else just accept that stones like this get effectively finer over time, and use something else like a coarse manmade waterstone when metal really needs to be hogged off.

Side note: My GF and I cook pretty much every meal every day, so I use my cutlery a lot. I like it to be able to shave arm hairs off when I use it, so I have to sharpen before each chopping session, and completely reset the bevel a couple times per year.

May I ask what knives you use?
Lots of very fine kitchen knives to be found these days.

I agree with Vasalis. If swarf, gunge or whatever would be the cause of the glazing it would be possible to wash or scrub the glazing off. Coticules e.g. never glaze unless they are used with oil because they are soft stones. With use the sharpening particles are freeed from the matrix, they don't get a chance to lose their teeth.

To add on (my first post).
I think this was with respect to kitchen knife sharpening.

I have had good luck cleaning stones with scouring powder & water (for example, Comet).

In particular, with diamond stones that stopped cutting, and with natural stones, and man made stones as well.

I stopped using oil and water on stones.

I gave one of my kids my old diamond plate and my new one has holes in the plate (10 bucks at Harber Freight, 4 stones on a block). It does not seem stop up as much as the metal collects in the holes. The diamond stone without the holes would stop up and become useless - then I figured out that it needed to be cleaned from time to time.

Jody

Originally Posted by Lemur

May I ask what knives you use?
Lots of very fine kitchen knives to be found these days.

I don't use anything fancy or special, just some very old Chicago Cutlery chef knives I bought on eBay. If I were a sushi chef, I don't think these would be good enough, but they will take an edge that will shave the hairs off my arm, and that's good enough for anything *I* ever do in the kitchen. Mind you, I've had to re-profile all my knives with a double-bevel grind to get them to perform like this.

I have some fancy-looking santokus called "Furi" which were a gift...These knives are a sort of metallurgical anti-miracle in that they are difficult to sharpen, AND go dull quickly. I do use them, though, because they are nicely balanced, and can be made sharp with reprofiling. But overall I don't recommend them.