Bench sharpening recommendations

[rswanson]

Hi all,

I'm moving from the Spyderco Sharpmaker into bench sharpening. I use a lot of carbon steels (1095, O1) but have some knives in S30, M4, and 3V so I have decided to go the diamond plate route. Maybe I'll get other water or oil stones later on but for now I'm trying to keep this simple. Currently, I have an 8x3 Dia-Sharp Fine but obviously I need to buy more stuff.

I need an option for cutting/resetting bevels. DMT coarse or extra coarse? Something else instead?

I think I'm good with the fine grit plate for general sharpening (please correct me if I'm wrong) but I want something better than the fine sharpmaker rods to finish on. I don't need mirror polished edges. Extra fine or EE fine DMT plate? Spryderco fine or UF ceramic plate? Something else entirely?

I'm open to suggestions since I'm just getting started with bench equipment, bearing in mind I need to work super steels and really want to minimize steps. As always, thanks in advance BF!

 

[FortyTwoBlades]

For cutting bevels you can use a coarse SiC stone no problem. At that grit range you're just gouging any vanadium carbides right out of the steel regardless of abrasive type.

 

[rswanson]

For cutting bevels you can use a coarse SiC stone no problem. At that grit range you're just gouging any vanadium carbides right out of the steel regardless of abrasive type.

Couple questions...SiC but not aluminum oxide? I'd rather not deal with oil. Part of the appeal of diamonds is being able to use them dry or worry about lapping.

Second, why even bother with diamonds at lower grits, if there's no difference for use on various steels? Is it just a convenience thing?

 

[FortyTwoBlades]

You can use aluminum oxide, too, just SiC is more aggressive and well suited for very coarse stones. You don't need to use oil if the bond of the stone isn't overly strong. Diamonds really aren't ideal for extra coarse work in my opinion, and tend to do best in the medium and fine ranges. The high pressure often used during bevel setting can cause premature wear to diamond plates. There are some contexts where they make more sense than other abrasives...but mostly in doing stuff like lapping/dressing other stones and the like. That's my opinion anyhow.

 

[maximus83]

+1 on Sic, for the coarse work. I have this dual-grit Norton Sic stone, use the coarse side a lot for bevel setting.

https://www.knifeworks.com/norton-8-pike-crystolon-175th-anniversary-edition.html

 

[Obsessed with Edges]

Couple questions...SiC but not aluminum oxide? I'd rather not deal with oil. Part of the appeal of diamonds is being able to use them dry or worry about lapping.

Second, why even bother with diamonds at lower grits, if there's no difference for use on various steels? Is it just a convenience thing?

If you happen to prefer a finished edge at coarse or very coarse grit, a Coarse or XC diamond plate will do it better on high-wear steels with heavy vanadium content (like S30V and beyond). If you're just wanting to hog off steel, along the way to a more refined finish (Fine/EF/EEF/polished), a SiC stone can do the coarser work well enough, after which following with diamond hones is the better way to refine it. At coarser grits, it's true, most of the work is just about 'scooping out' very hard carbides, instead of cutting or thinning them, or refining their shape. BUT, I've noticed in my own uses, the coarser diamond hones will still be able to cut & shape those carbides as well, to some degree better than SiC can do it; so, the end result will be a coarse-finished edge with noticeably better hair-popping capability, which won't be as easily attained with a SiC stone or something lesser.

Basically, with high-wear steels, diamond hones will make it a lot easier to attain hair-popping sharpness with less fuss in the end, regardless of the desired edge finish preference.

Very coarse aluminum oxide (150-grit and lower) can also be used to hog off steel. But it'll be noticeably slower on high-wear steels, and burring issues will be much worse than if done with something like SiC/diamond. It's the heavy burring issues, for me, where I draw the line in determining if I want to use aluminum oxide or not with a given steel. If the burring is very heavy, that sort of screams to me that something more clean-cutting would better-suited to the work.

 

[maximus83]

OP a typical sequence I've been running that includes Sic:

*For resetting or reprofiling bevels, or edge repair: 120 grit SiC Norton stone
*For coarse sharpening and apexing: coarse DMT diamond stone
*For refining and finishing: DMT extra-fine diamond plate, or Spyderco UF ceramic, or both.

Some folks, at my first step above, rather than SiC are using something diamonds in the 200 range, like the DMT extra-coarse. I believe @HeavyHanded still does.

 

[rswanson]

If you happen to prefer a finished edge at coarse or very coarse grit, a Coarse or XC diamond plate will do it better on high-wear steels with heavy vanadium content (like S30V and beyond). If you're just wanting to hog off steel, along the way to a more refined finish (Fine/EF/EEF/polished), a SiC stone can do the coarser work well enough, after which following with diamond hones is the better way to refine it. At coarser grits, it's true, most of the work is just about 'scooping out' very hard carbides, instead of cutting or thinning them, or refining their shape. BUT, I've noticed in my own uses, the coarser diamond hones will still be able to cut & shape those carbides as well, to some degree better than SiC can do it; so, the end result will be a coarse-finished edge with noticeably better hair-popping capability, which won't be as easily attained with a SiC stone or something lesser.

Basically, with high-wear steels, diamond hones will make it a lot easier to attain hair-popping sharpness with less fuss in the end, regardless of the desired edge finish preference.

Very coarse aluminum oxide (150-grit and lower) can also be used to hog off steel. But it'll be noticeably slower on high-wear steels, and burring issues will be much worse than if done with something like SiC/diamond. It's the heavy burring issues, for me, where I draw the line in determining if I want to use aluminum oxide or not with a given steel. If the burring is very heavy, that sort of screams to me that something more clean-cutting would better-suited to the work.

Sounds like aluminum oxide is out then, due to the heavy burring likely. Next question- is it easier to control a fine burr formation with diamonds vs SiC, or this a push and more a matter of technique?

I certainly don't want to buy an expensive diamond plate and then wear it prematurely with increased pressure on cutting bevels. Is this unavoidable?

 

[353]

If I lost all of my sharpening gear I would buy this:

- DiaSharp 8" Double sided benchstone with coarse/fine. I have extra coarse and extra fine too but almost never use them.
- Spyderco medium benchstone
- Spyderco fine benchstone
- A good strop and a diamond spray compound. Maybe also a second strop to have a polishing compound on.

 

[Jason B.]

DMT XXC, XC, C

For your carbon steels I would strongly recommend a simple combo waterstone or oil stone of your preference. Both do much better than diamond plates on simple steels in regards to speed and edge quality.

 

[Obsessed with Edges]

Sounds like aluminum oxide is out then, due to the heavy burring likely. Next question- is it easier to control a fine burr formation with diamonds vs SiC, or this a push and more a matter of technique?

I certainly don't want to buy an expensive diamond plate and then wear it prematurely with increased pressure on cutting bevels. Is this unavoidable?

I've liked diamond because it's the best at minimizing burring overall. That's directly related to how easily and cleanly it cuts the steel, no matter the carbide content. SiC does OK, though maybe not as easily (cleanly) as with diamond, depending on the steel being worked.

No need for increased pressure on diamond plates, no matter the task. They'll work better at a light-to-medium touch anyway, and even lighter at the finishing end, where a very light touch will be rewarded. Anything heavy isn't going to speed grinding at all, and won't be good for the plates either.

Something to consider also: If one KNOWS their touch is a bit heavy, and especially if a heavier approach is their preference, a SiC stone would suit that more easily.

Along the lines of Jason B's recommendation above for your simpler steels (1095, O1, simple low-alloy stainless), a basic aluminum oxide oilstone can work very, very well and leaves a very nice finish and to wicked sharpness. Think of something like Norton's India in Coarse/Fine, for example, as a nice oilstone for such use.

 

[maximus83]

I've liked diamond because it's the best at minimizing burring overall. That's directly related to how easily and cleanly it cuts the steel, no matter the carbide content. SiC does OK, though maybe not as easily (cleanly) as with diamond, depending on the steel being worked

I have not reproduced this result in my own sharpening of quite a few super steels (s30v, s35vn, M390, 20cv, CTS-XHP). Doing bevels on a very coarse Sic stone like the progression I posted above, I see no significant different in burr formation with these steels working on a low-grit SiC stone like the Norton JB8 versus using something like a 140 Atoma coarse diamond plate. There are other kinds of differences that may be worth noting, and that may push someone to use diamonds or SiC. But I've not seen any noteworthy difference in burr formation at this stage between SiC, and diamonds. And actually, at this lowest level of coarse grinding, I prefer working with a friable Sic stone. OP asked about options for cutting bevels, that's where this comes into play.

The really noteworthy performance difference in sharpening where using diamonds starts to pay off is when you get into higher grits, say the mid 200's and upward, where you can actually conceivably put a finished working edge on your super steel blade. I experimented quite a bit at each grit stage: for example I compared a 120 grit Sic with the 140 grit diamonds. Then I compared a 240 grit SiC with a 220 mesh diamonds (DMT XC). Then at the 300's, compared the Norton Crystolon fine at about 320 with the DMT coarse (about 325 mesh). It was in the 200's grit range that I started to notice a significant difference in the resulting edge finish between using SiC, and diamonds. After trying it both ways for a bit and seeing how high I could go with Sic without impacting the sharpness, I finally settled on the progression above that I've been using. In cases where I don't need to profile an edge but am just doing routine sharpening, I can usually just start with the coarse DMT now as the best foundational sharpening stone.

 

[Obsessed with Edges]

The ease with which a diamond hone handles otherwise more burr-prone steels is apparent, and is why I generally prefer them for overall ease of sharpening across a wider range of steels. I've come to recognize a tendency to minimize burrs as a good indicator the abrasive is doing a more efficient job cutting the steel; it also points to the abrasive's ability to handle the carbides, if they're present in significant amounts. That's what was driving my comment about a diamond hone being preferable to me, in minimizing burring across the spectrum overall, while still being able to easily sharpen anything put to them. It's more noticeable with low-/mid-alloyed stainless steels like 420HC and (especially) VG-10 or ATS-34 at fairly high hardness of 60+ HRC, still capable of producing tough burrs even then. So, the qualification of 'depending on the steel being worked', in my previous comment, is primarily aimed toward steels like those.

So-called 'supersteels' at decent hardness usually don't burr as much anyway, and some barely at all; so it's essentially moot with those. The wear-resistance is the main concern there, and is the greater determining factor for choosing a diamond hone to sharpen them, especially in refining steps.

 

[rswanson]

Great feedback everyone, thanks. So it seems like my best course would be to pick up a dual grit SiC stone, coarse/fine, for both setting bevels and edge repair on all steels, as well as working my carbon blades up thru fine grit. I can use my fine grit DMT plate for refining high wear resistant vanadium steels.

If I can ask another question, what extra fine grit solution should I be thinking about here? A ceramic stone or stick with diamonds? What's the preferred selection to get a clean, hazy edge...specific product recommendations, please.

 

[wade7575]

If you want good diamond stones look at Gritomatic and look at the Venev diamond stones I think they make other size's then just the Edge Pro and KME size,also if you don't care about the stones being Edge Pro size look into the Metallic Bonded CBN I have a set of those and nothing on the market cut's as fast as those do they are under Poltava diamond tools on his website,also the Metallic CBN anchor's them in much better and you don't get the tear out from them like you do on a diamond plate,they are also 3mm thick and they pretty much don't wear at all an the CBN is all the way threw out the Metallic bond.

I use the CBN on S110v and it cut's so easily when compared to any other stone it's amazing.

 

[Obsessed with Edges]

Great feedback everyone, thanks. So it seems like my best course would be to pick up a dual grit SiC stone, coarse/fine, for both setting bevels and edge repair on all steels, as well as working my carbon blades up thru fine grit. I can use my fine grit DMT plate for refining high wear resistant vanadium steels.

If I can ask another question, what extra fine grit solution should I be thinking about here? A ceramic stone or stick with diamonds? What's the preferred selection to get a clean, hazy edge...specific product recommendations, please.

If mainly for the supersteels, the 'clean, hazy edge' will best be done on something like an EF or EEF diamond, and will produce a finish matching that description specifically. Something like DMT's EF (1200 mesh/9 micron) will leave a very fine satin, but still with some perceptible tooth in it's bite. The EEF (8000 mesh/3 micron) will begin to show some hazy polish on such steels. Again, it's mainly about the diamond's ability to refine the carbides at the edge, making the difference with supersteels containing much vanadium (4% and higher).

For simpler steels like 1095 & low/medium-alloyed stainless, a medium ceramic, such as Spyderco's brown/grey, will produce that clean & hazy finish, with some nice bite. A medium Arkansas stone will also work well with those, leaving a similar finish; I prefer such a stone for 1095 and CV, for example. A Fine India (360-400 grit) will leave a somewhat more aggressive, toothy edge, but is still very nice for such steels. You still can use the EF/EEF diamond for those, if you want to; but it's not really necessary for those steels. I've often liked using a Fine/EF diamond for decent quality kitchen stainless, for example, simply because of the great 'bite' it leaves on such edges. But they'll also respond nicely to other stone types, like the India and Arkansas stones.