Need Recommendations on Freehand Sharpening Stones

[Steel_Drake]

the sigma 2 are made of aluminum oxide, not silicon carbide...... Just FYI...

Only the 400x, 1200x, and 13000x stones are aluminum oxide, the rest of the Sigma Power Slect II line is silicon carbide. Ask Stu from Tools From Japan if you don't believe me.

We went through this once already, I have the sigma power select 2 1000, and the shapton glass 1000. The sigma doesn't cut noticeably faster and it wears waaay more rapidly. I bought the sigma as an experiment and wouldn't do it again.

The physics of how friable abrassives work make this quite unlikely, as the shedding of used abrasive and exposure of fresh abrasive particles is positively correlated with cutting speed.

If you used a lot of force sharpening a simple steel, I guess it is theoretically possible since you could be getting the SPS-II stones to rapidly shed unworn grit with sufficient force, but in my use I sharpen with a fairly light touch and do actually sharpen HAP40 and ZDP in the same amount of passes as VG-10 with them.

 

[Jason B.]

HAP40 and ZDP @ 65+ will never sharpen at the same rate as VG-10, I have some of the best waterstones available including some Kohetsu stones that would probably put the SPS-II to shame. When the stone cuts faster softer steels like VG-10 grind faster, the increase in speed is not just for the harder steels...

I've used some Sigma stones before, but no stone will make up for steel hardness and alloy content and make them all the same. Harder steel will ALWAYS sharpen slower and high alloy steels will ALWAYS resist inferior abrasives.

And just so we are all on the same page,

HAP40 and ZDP are hard and fairly wear resistant but DO NOT contain Carbides hard enough to cause any issue. Even Aluminum Oxide is harder than Tungsten, and of the steels listed only HAP40 would have enough Tungsten to form a high volume of hard carbides. The 2% Vanadium is doing more for grain refinement. ZDP's main carbide former is Chromium and thats softer than Tungsten so no real trouble there.

I'm sure the SPS-II are very fast and work well, but the argument is overstated and not all that factual.

 

[Steel_Drake]

HAP40 and ZDP @ 65+ will never sharpen at the same rate as VG-10

I'm sure the SPS-II are very fast and work well, but the argument is overstated and not all that factual.

Jason,

I can understand why you would think that, but when Stu from Tools From Japan did a direct speed comparison between various waterstones here, he found that the Sigma Power Select II stones both utterly decimated the Shapton (and any other waterstones) for speed on HSS and precisely sharpened HSS chisels at exactly the same rate as white steel chisels:

 

[Jason B.]

Its a good data point but not a bible.

You are comparing HSS which is usually A2 vs White steel which is similar to 1095 with a bit more carbon.

You are also forgetting that White steel can be taken to 65 HRc while A2 would be in the 60-62 range. That difference in hardness would make the steels about equal in wear resistance thus making them sharpen at similar speeds. He is also comparing laminated blades vs homogeneous blades and blades of different widths. In reality, its a test with far too many variables.

 

[Steel_Drake]

Its a good data point but not a bible.

You are comparing HSS which is usually A2 vs White steel which is similar to 1095 with a bit more carbon.

You are also forgetting that White steel can be taken to 65 HRc while A2 would be in the 60-62 range. That difference in hardness would make the steels about equal in wear resistance thus making them sharpen at similar speeds. He is also comparing laminated blades vs homogeneous blades and blades of different widths. In reality, its a test with far too many variables.

Jason,

If that is the case, why didn't the other stones cut them at the same speed? Why was the SPS-II 1k the only stone to cut them at the same speed?

Additionally, the HSS in that graph is very unlikely to be A2 as A2 was used in the first part of the comparison, pictured above, while the second graph quoted in the above post was for Japanese chisels made using Japanese steels. Furthermore, the massive gulf in cutting speed results on the King Deluxe, which was essentially entirely unable to cut the Japanese HSS while it still worked fine (if slowly) on the A2 also indicate the Japanese HSS used in the comparison to be significantly harder to grind than A2.

Nonetheless, for the sake of completeness I have emailed Stu to check if he knows which HSS is used in that chisel and at what HRc.

Ultimately, the larger points still stand: Firstly, that the SPS-II were significantly faster on all steels than any other stones, with the relative speed advantage over other stones increasing on more wear resistant steels. The SPS-II stones therefore minimize the extra time needed to grind more wear resistant steels compared to any other waterstones.

Again, in my personal usage I have actually sharpened VG-10, 440C (@ ~62 HRc), HAP40 and ZDP-189 knives with similar edge bevel areas in identical numbers of passes on each stone and identical sharpness test results afterwards (e.g. identical push-cutting ability on phonebook paper, tomatoes, hht, etc.). (Of course, it's possible I am doing more passes than strictly necessary on the VG-10 and 440C since I was used to sharpening them on my older, slower stones).

 

[knifehunt]

Also just looked up the CKTG 400/1000 grit. Wow, only $35. That's cheap! You'd use just this and a strop? That's it?

Yes, I've been using the same setup for some time, and the results are amazing. The CKTG 400/1000 is a fantastic stone, and cheap to boot. I have diamond stones that cost twice as much for a single grit that are no better performance wise. This stone together with the diamond paste will provide incredible results for well under $100...

 

[fsatsil]

Additionally, the HSS in that graph is very unlikely to be A2 as A2 was used in the first part of the comparison, pictured above, while the second graph quoted in the above post was for Japanese chisels made using Japanese steels. Furthermore, the massive gulf in cutting speed results on the King Deluxe, which was essentially entirely unable to cut the Japanese HSS while it still worked fine (if slowly) on the A2 also indicate the Japanese HSS used in the comparison to be significantly harder to grind than A2.

A2 is not a HSS my guess would be that it was something like M2 or a similar Japanese equivalent.

 

[mycough]

Jason,

I can understand why you would think that, but when Stu from Tools From Japan did a direct speed comparison between various waterstones here, he found that the Sigma Power Select II stones both utterly decimated the Shapton (and any other waterstones) for speed on HSS and precisely sharpened HSS chisels at exactly the same rate as white steel chisels:

A chart made by the guy selling the fastest stones? Mmmmkay. Time to break out your trusty SEM Drake...
Russ

 

[mycough]

"But Stu says......."
Where is that ignore button?...
Russ

 

[Steel_Drake]

"But Stu says......."
Where is that ignore button?...
Russ

Please never interact with me in any form whatsoever again.

 

[bucketstove]

A chart made by the guy selling the fastest stones? Mmmmkay. Time to break out your trusty SEM Drake...
Russ

well, toolsfromjapan is also selling the slowest stones from the chart
a guy checking his inventory of stones for speed on a bunch of knives he has
nothing wrong with that

 

[winnerone23]

Before I got here..

I've been using this little stone for years. Probably a decade, to most all of my sharpening duties.
Lots of touch ups, lots of co-workers butter knife's, reprofiling, etc..

Since I got here..

One of my dad's friends bought a Lot, at a auction and gave me these. It came from me talking about reading and learning, more about sharpening..

After reading this thread and many others, I grabbed these..

Oh, the joys of sharp things!!!

And of course, I had to add a Sharpkeeper..

I never really had a problem with sharpening or what I had, to sharpen with.
Be it a landscaper block, concrete, semi rusty handle on a track hoe, whatever..

But years of practice, constant technique learning, and the right stones, make for a very new (to me) hair popping experience!

Thanks BF!