Water Stones

IMO using sandpaper, concrete etc as a flattening stone is just a poor idea. A respectable flattener for most is $12 and a very nice one is $45. It's not like a quality flattener should break the bank. Not to mention concrete can be pretty darn coarse to say the least.
Do yourelf a big favor and get a flattener.
I'd suggest you get yourself a quality DVD on knife sharpening as well. It helps a LOT to see it being done properly.

That might work on a 800 but it's surely not what I would do on a stone 5k or over (if that). I would just wait until you can get a proper flattener. OTOH I understand we all have a budget. Here's a few vids to watch in the mean time. :thumb:


YouTube - Knife Sharpening 1

YouTube - Knife Sharpening 2

YouTube - Knife Sharpening 3

Questions and answers, eh?

Q1 and 2: A:

You don't use it on the coarse surface, only on the 6K. After the stone is flattened and soaked, but before sharpening, you rub the nagura on the sharpening surface to get a "slurry" going. Depending on the type and hardness of the stone and the nagura the slurry will consist of various ratios of abrasive, binder and nagura. It's not really an issue with an Ice Bear (King's best clay binder stones) 6K, but you want to go easy on very fine, hard stones as all you'll get is a 100% nagura slurry, which doesn't really help much.

You'll also use the nagura to dress (i.e., lap) the 6K after flattening. The surface should be (relatively) smooth -- not counting slurry -- before taking a knife to it.

The "black discoloration" is old slurry consisting of binder, abrasive, and swarf (metal filings which came off the knife). It actually does a lot of the work during the sharpening process -- some stones you just leave it between flattenings. Your stones work best with frequent rinsing during sharpening, and should be rinsed and cleaned before storage. The stones probably won't come completely clean, and that's OK.

A:

Lots of people start out flattening on concrete -- usually a flat spot in their driveway. I don't think I'd go to the trouble of having a small slab poured. It could be workable, but wouldn't be ideal.

Speaking of a glass plate, you can use your friend's concrete, a discarded piece of granite countertip, a flat ceramic tile, etc., as reference plate.

If you do use sandpaper, use wet-dry. You can flatten an Ice Bear pretty well on sandpaper. Large surfaces like a full sheet of sandpaper can be helpful in that you can flatten the entire surface at one time, without accidentally dishing. However, sand paper clogs pretty easily and requires frequent replacement. Dry wall screen is better.

And as Duck said, there are a myriad of smaller, inexpensive alternatives which also work well. You have to pay more attention to leveling; but they are faster and end up less expensive in the long run.

To get the sandpaper to stay, just spray the reference plate and back of the paper with a little water. That's enough to hold the paper.

Q: A:

Yes. But, sometimes mold can form. If it does, scrub the stones and soak them in a mild solution of household bleach. After a sharpening session, you can add the bleach to your stone bucket and soak them for fifteen minutes or so after rinsing and before drying.

Hope this helps,
BDL

Some very coarse SiC stones can work as flatteners. The problem is they tend to clog and need a lot of cleaning with a brass brush or something similar. Others, just clog way too fast to be practical. I don't know enough about yours to say which it is. If I'm not mistaken, the "Peacock" Duckfat recommends is an SiC of "the good type."

A ceramic flattener, something like the Norton or Naniwa (around $25) with grooves cut in it is easier to clean, and are also decent, budget flatteners. Unfortunately both types, SIC and the soft, coarse ceramic flatteners wear quickly.

Wear doesn't just mean they get used up, unfortunately it also means dishing. So, in addition to cleaning, the flattener will also needs regular flattening or cannot be used as a "reference." Still, even with their problems, inexpensive "flattening stones" are a good solution for beginners or those who don't do much sharpening.

Another alternative is a coarse diamond stone like a DMT XC or XXC (don't know what you've got in Oz). They're very efficient, easily cleaned, and so on. The limitations are size and price.

Ice Bear is King's best, clay-binder line. I've never owned an Ice Bear, but as a clay binder stone and should be very easy to flatten on a flat piece of driveway, or 80#, then 220# wet-dry sandpaper. When the sandpaper clogs (which will happen even with a lot of rinsing) or wears down, just throw it away. Sandpaper is cheap, large sizes make even flattening and "referencing" your progress simple; but it's slow, messy, and clogs quickly.

Dry wall screen, if you can get it, is longer lasting and easier to clean than sand paper -- shoot for 180#. It's still a lot slower than a diamond stone like a DMT XC or XXC, but that shouldn't be much of an issue with your soft stones. A secondary benefit is that you can buy large enough pieces to flatten the stone perfectly and all at once -- which makes referencing easy. Here in the US of A, $11 buys a two or three years' supply of 9" x 11" screen (don't know what it would set you back down undah). Of course, you'd need a piece of glass, metal, stone or tile to lay it on, too. So figure another few AUD.

Most clay binder stones, like your Ice Bears, dish quickly -- especially combi stones where each grit only has one side. You should probably flatten your 800# at least every other time you use it.

BDL

A flat section of concrete such as the floor of a basement or garage will work for flattening. To be honest, a home sharpener can get away with using finer grit stones for a good while before they need flattening. I know it's considered "best practices" to flatten them frequently but you can hardly perceive the wear on a 5k or 10k stone even after a dozen knives. A 1k will do quite a bit of sharpening, too. That's not to say you should let it go, just that it's not the end of the world if your stone's not dead flat.

Kalach,

My brother: Yes.
It is. Is it the best flattener? Maybe, but not necessary -- especially for stones as soft and easy to flatten as your clay binders.
It will. You may find the jump from 800 to 6000 difficult. If so, we'll talk about an affordable medium grit. My inclination is to suggest a Naniwa SS 2K; but let's hold off for awhile.
You can use both sides on the vast majority of stones; and the few exceptions tend to be resin binders. Ice Bears are clay binders, but I can't give you a definitive answer. Call or email your seller -- if they don't respond, try emailing Tools for Working Wood. Yes to sanding it out.

Start with the 800# and see how it goes. Your coarse SiC oilstone will scratch up the side of the knife (guaranteed) beyond the bevel shoulder, and may not be any faster. Better to go slow at first.
Sharpening is one of those subjects where the more you learn, the better able you are to appreciate the abysm of your own ignorance.

Life's a beach,
BDL

Regarding flattening frequency IMO all stones should be flattened both sides right out of the box. How frequently you need to flatten will depend on the stones you use, how soft they are and your technique. A noob using excessive pressure may well need to flatten a stone like a resin based Naniwa SS every use. A flattener or a method of flattening is essential to getting started. I don't know where others live but good luck finding a driveway or a basement that is flat in my area. Both of those applications are typically troweled or "broomed" here. A long ways from smooth not to mention for drainage purposes not many are truly flat. Hey it may work but then again you may damage a good stone. IMO flattening a quality stone on the driveway or the basement to save $20 give or take is penny wise and pound foolish. For the thrifty I can see the logic in the dry wall screen.
Just My .02 adjusted fer inflation and dah internet. :lol::peace: