Wear and tear on the stone using Stone Grader SP-650

[Jimmy R Jørgensen]

Reading about the gridstone or stone grader : Stone Grader SP-650

i find this info, and have read the last part (Made in bold) many times and wonder, how often do i have to do this, and or when do i have to do this, and is it really true that it doesn't wear and tear on the stone if you do it all the time, i've been told to do it every time i sharpen a knife, and is a bit sceptical. Because in my mind it have to be "hard" on the stone to do that, and the stone isn't free you know. So guy and girls. how often do you use the Stone Grader SP-650 and in your experience how hard is it on the stone when using the Stone Grader SP-650

The grading of the grindstone is made by pressing the fine side of the Stone Grader onto the grindstone, which makes it work as a fine grit stone (approx. 1000 grit). When pressing the coarse side onto the grindstone, the smoothened surface is returned to its normal condition (220 grit). This process does not place excessive wear on the grindstone and can be repeated any number of times.

[Rob]

use it frequently and use it hard.  It will not denude the grindstone in any measurable way.  If you DONT do it the grindstone will glaze over and stop cutting making it impossible to sharpen anything.  Don't worry about it, just lean hard on the grader to resurface the stone.

[Jimmy R Jørgensen]

Will i know by touching the stone if it need a good grind? 

[Rob]

you'll know because your chisel/plane iron etc will stop being ground as the grindstone glazes (stops cutting).

When you have freshly graded the stone with the 220 side of the grader, it should feel slightly rough to the touch.  When it is graded to the 1000 grit side, it feels smooth.

[Jimmy R Jørgensen]

Do you always go 220 first and then 1000 grid. Or does that depend on how damaged the edge is, talking about knifes in general. i'm tottally new to this, sharpende like 3 knifes now. so i might be asking really stupid questions.. I do apologizes about that.

[Rob]

don't worry about asking stupid questions....if we didn't ask stupid questions...we'd all be stupid :-)

You grade the stone to whichever cutting strength the job needs.  If you're just tickling an epensive knife with no dings, use the 1000 grit and grind away from yourself.  If you're sharpening a plane iron with a 1mm ding in it, use the 220 grit and grind towards yourself for a more aggressive cut AND regrade the stone to 220 grit frequently.

Generally speaking I would say almost always grind knives at 1000 grit and away from yourself as you don't want to remove much steel at all.

[Herman Trivilino]

Hi Jimmy and welcome to the forum. Like others have said, one of the purposes of the stone grader is to refresh the surface of the grindstone. This is necessary because it quickly clogs with particles of steel. You can actually hear and feel it happening when the grindstone has been prepared to the finer 1000 grit state.

In my opinion using the stone grader does put wear on the grindstone, but it's necessary to the process. Trying to save that wear is futile. It'd be like trying to save on brake pad wear by not using your brakes! Brakes are designed to wear, it's part of the engineering that goes into the functioning of the device. The same is true of the Tormek grindstone.

Do you always go 220 first and then 1000 grid. Or does that depend on how damaged the edge is, talking about knifes in general.

It takes a little experience to figure this one out. Certainly you can always start with the coarse grit and finish with the fine. I definitely do that if there are nicks in the cutting edge. On the other hand, if I have a fine piece of steel I'll want to start with the finer 1000 grit. If I do that, and I find that I'm not raising a burr, I'll switch to the coarser 220 grit.

I always keep two rags handy. One for wiping away water from the blade, the other for wiping away honing compound. When I use the rag to wipe away the water I see if the burr on the knife has snagged threads all along it's edge. If it has then I know I've raised a burr and I'm ready to switch to the other side of the knife.

[Ken S]

Jimmy,

Welcome to the forum.  I think the key words in the quote are "excessive wear". The grindstone is consumable; we expect it to wear out eventually. Using the stone grader cannot help but wear the stone, but very little, much less than using the truing tool.

Ken

[Jimmy R Jørgensen]

Generally speaking I would say almost always grind knives at 1000 grit and away from yourself as you don't want to remove much steel at all.

so to grind with the stone going away from myself i would use the "bar" in the horizontal position or?

[Rob]

That's it :-)

[Jimmy R Jørgensen]

What about the Tormek Slibesten SJ-200 is that a bit overkill for normal kitchen knifes etc?..

[SharpenADullWitt]

In other posts, recently, there has been some discussion about that stone, verses the leather wheel and compound.  (very similar grits)
Use of that stone, means skipping the leather wheel, and is a polishing stone, verses a grinding stone (you would have to use it on the knives, frequently, and it won't do chips).  Where I saw it recommended, was for use on things like Sushi knives (and I know a Japanese chef and German chef, so I know there are some different needs).  I would love one of those stones to try, honestly but I think it is just a want, no where near need (or even worth it for my uses).

[Ken S]

"The stone isn't free, you know"

Jimmy, I detect a common beginning situation, "precious grinding wheel syndrome". Hopefully you will soon soon come to see the grindstone as a consumable, just like brakeshoes. Tormek grindstones, like all abrasives, are designed to be consumed. Like brakeshoes, the consumption period is extended.

The worth of the grindstone is the edges sharpened, not in the stone itself.

When the stone wears out, buy another one. The good news is that the stone has a long life, so the cost per edge is low. One pleasant side effect of this cost is the increase of skill.

You refer to the SJ-200. Are you using a T4? If so, you may have to replace the grinding wheel more frequently. However, the cost of a replacement is just over half the cost of a T7 wheel. Keep in mind that many users find that the original wheel will last for the duration. Don't worry;  be happy.

Ken

[Elden]

In my opinion using the stone grader does put wear on the grindstone, but it's necessary to the process. Trying to save that wear is futile. It'd be like trying to save on brake pad wear by not using your brakes! Brakes are designed to wear, it's part of the engineering that goes into the functioning of the device. The same is true of the Tormek grindstone.

   My Dad got many more miles out of brake shoes and/or pads than most people, myself included. It was because he anticipated his stops and would slow down ahead of time. He also got more mileage out of tires than most.

   However in regard to the Tormek grinding wheel, the only way to save wear and tear is to quit using it! 

[Rob]

I thought Herman's brake shoe analogy was a cracking good one :-)