SG Grindstone vs Diamond Wheels

[RichColvin]

I've seen a number of posts regarding the question:  

Should one invest in diamond grinding wheels or go with the SG grindstone?

From my experiences with all 6 grinding wheels (SG, SB, SJ, DC, DF, & DE), I have come to believe that a better question is

Should one invest in diamond grinding wheels or go with the SB grindstone?

I find that I use the diamond grinding wheels for harder metals like 

• Wood turning tools (usually HSS)
• Carbide inserts for wood and metal lathe tools
• Drill bits

These were previously sharpened using the SB grindstone.

And, I use the SG grindstone for almost everything else.

So the question to be answered is,

What do you plan to sharpen?

If the tools to be sharpened are harder steels, then go with either the diamond grinding wheels or the SB grindstone.  Do note that the SB grindstone can be regraded, so I believe it is comparable to the DF + DE grinding wheels.  And the SB is lower cost than the two diamond wheels.  

If you are not needing to sharpen tools with such hardness, go with the SG grindstone.

If you need both, my advice is to start with the SG & SB grindstones.  Eventually, the SB grindstone will wear down and need to be replaced.  Then you can consider getting the diamond grinding wheels.


I welcome thoughts and feedback on experiences from others. 

[Ken S]

Interesting thoughts, Rich.

One thing which has puzzled me over the years is how little attention has been given to the SB and, to a lesser extent, to the SJ. This lack of attention predated the introduction of the diamond wheels. I remember when pioneers like our own Wootz and also Derek from Perth first wrote about the difficulties of using early CBN wheels. The problem was that the wheels dished and were no longer flat. This problem was not unique to CBN; all of our wheels became out of true with use. The difference was that wheels like the SG and SB could be retrued using the TT-50 truing tool. Admittedly, restoring the wheel to true reduced the diameter somewhat; however, the CBN alternative was a wheel which gradually became further out of true and could not be corrected.

Examining the handbook, I could only find one paragraph covering the SB. Even that one paragraph was shared with the SJ. As valuable as I find both the handbook and the online classes, I have never understood why the SB has been so ignored. The glamour wheel, the SJ, gets more attention in the classes, which puzzles me. The SJ adds the spit and polish shine to already sharp edges. The SB can do the really hard work of efficiently grinding heavier sharpening harder steels.

Years ago, we had posts about the SB. These were frequently complaints about the wheel glazing. In fairness, there were a very few real experts who had good results with the SB. These were few. Eventually the SB seemed to fall into oblivion.

The SB, like the SG, can supposedly be graded with the stone grader. I would like to read successful posts about this; I have never had much luck with the SB and stone grader. The online classes do a good job of demonstrating and explaining how to use the TT-50 and the stone grader; however, this is always done with the SG. If the SB truly is  an easily gradable stone, I believe this versatile stone deserves more attention. Especially if gradable, I think it can fill the gap between the SG and diamond wheels and do so at much lower cost than either diamond or CBN wheels.

Ken

[tgbto]

As far as I am concerned, I use the SB mainly for HSS drills.

The SB works a charm for those, and I prefer it to diamond wheels because I don't have to worry about pressure (which I have a harder time adjusting with the drill jig than with the knife jig).

It does tend to glaze a bit, but the "Wootz maneuver" with a coarse diamond stone quickly restores it to a duly aggressive surface. I have only trued it once and slightly so since I own it.

[John Hancock Sr]

I use the SG for regular knives, carbon steel chisels, plane blades, and axes. For HSS plane blades, planer blades, chisels, and Japanese knives I use the diamond wheels. The SB would also be fine but I bought the diamond wheels.

[Columbo]

Ken I too, would've liked to see a little more input concerning the SB.
Yesterday I tried to revive an old HSS neat clever by first using these resin bonded wheels that are 100g and 1000 grit. Then deburring on a Scotch-Brite wheel, followed by a flappy leather wheel and got nowhere to a consistent, smooth edge. This was all due I think more so in the way I had the latest knife jig in place on the Cleaver.
Anyway, let's forget about this course of action.

Then I tried CBN wheels in 160, 400 and thousand grit and eventually, this helped give me a cleaner edge, but yet not sharp enough. I mention this clever, original edge from the start was all over the place anyway. And of course, Scotch Bright wheel to remove the burr, followed by the leather wheel coded with blue compound. In the end. It gave me a better edge, but still not sharp enough. Now I wonder, with this being my first cleaver I have ever sharpened thus far and expecting under 90 on the bess scale, That may be a 160 bess marker that I had was adequate enough.

Then I remembered the SB Stone I have that seldom got used. from my understanding this SB Stone is more so used for HSS steels. So there I went first grading it with its lowest grit then of course regrading to the 1000 Which seem to have given me the best in a cleaner edge if you will.
But by that time, I was tired and left it alone with no holding thus far. I'll tackle it later today. But what I want to say is by far the SG gave me better improvements. But I also can't say that it did it on its own because I did two processes prior to the SV scenario. Anyway, what am I saying I don't know quite honestly. But I agree with you. I don't see much input, feedback, talk around the usage of the SB. That's the price of potatoes for me today from a still learning recipient of this fine community.

Thank you, Ken

[Ken S]

Filippo,

I certainly don't have all the answers. One idea strikes me as deserving more attention. It is briefly mentioned in the online class covering the T2, and I have heard it mentioned in conversations and emails with Tormek staff over the years. The T2 class gives it the best coverage. It is simply taking one more light pass on each bevel This single light pass on each side removes most of the bevel, reducing the work needed to deburr the edge.

More later.

Ken

[MerryMadMick]

Not sure if its relevant, but I use the SB as a first pass after I reset primary bevels on an aggressive CBN wheel or to repair heavily damaged chisels or plane irons.  I leave it set to an aggressive grit using a 80-grit diamond plate.

I don't sharpen carbide all that often, mainly O1, A2, W2, and PM-V11, but when I do the SB works the charm.  I'll finishing the edge with the SG set to a fine grit with a 400-grit diamond plate.