On the Feedback of Sharpening Stones

[Jimmy Harris]

So I know a lot of people love their sharpening jigs and claim it's the only way to get consistent and repeatable angles on their blades. Which, being someone who's freehand sharpened their whole life, always struck me as kind of odd. I get it if you don't do much sharpening or are new the realm of sharpening, but for us hand tool woodworkers, experience is not a problem. So it would seem to me that most of us would get pretty good at freehand sharpening and not need these jigs to get those consistent and repeatable results we all desire. Yet those jigs remain very popular. Which brings me to something I hear a lot about in cooking and blade forging communities that I don't hear much about here, and that is whetstone feedback.

Often times what separates a good whetstone from a great whetstone is its feedback, or its ability to tell you if your angle is off by just a slight amount. It feels and sounds wrong if you don't hold that angle precise. And the best stones for this are often soft, water stones that need a long soak. And because they wear quickly and need a long soak before each use, they're not convenient for us woodworkers, who often don't have access to a sink in our workshop. So we're more likely to gravitate towards the splash and go stones or the diamond stones that have terrible feedback. If you've never had the pleasure of using a Naniwa Aotoishi, I recommend you try it one day if you ever get the opportunity, just to see what it's like. A good whetstone with excellent feedback will really teach you good techniques that you can take over to other stones with less excellent feedback. It'll make it more obvious what you're feeling and listening for and make your mistakes more apparent, like a good teacher who doesn't let you stray from the path.


I now use sandpaper on plate glass myself, and while the feedback isn't as good as it is with most of my stones, the stones taught me what I'm looking for, so I only need subtle cues at this point. This way, I don't have to mess with flattening or soaking stones. And when I look at the whetstone being sold at places like Woodcraft and Rockler, I see a lot of diamond plates and Shapton stones. Shaptons are great stones; I own a few myself. But they're not exceptional at feedback. They tend to be too hard for that, as they prioritize durability and cut speed over feel. They're better for those with lots of experience than for someone who's still learning. In fact, I don't see any good beginner stones with good feedback at these woodworking stores.

So is this why the sharpening jigs are so popular these days? To compensate for the difficult yet convenient whetstones we have access to? Not that there's anything wrong with that. Whatever works for you, obviously works and there are tradeoffs no matter which road you take. I'm just curious if this might explain the ubiquity of sharpening jigs among woodworkers, who probably sharpen several times a week, if not several times a day.

[Reed Gray]

Well, if there were not any sharpening jigs, then we would all sharpen by hand and eye. I do sharpen all of my lathe tools free hand, but I use jigs for chisels and plane irons, and I would guess that part of that is because I am new to the hand tools for flat work. As for what works best, more than anything, it is what works best for YOU. I prefer the diamond plates, and have a couple of the Shapton plates as well, Pretty simple to use, less muss and fuss. I may eventually go to free hand sharpening. I think it is interesting that for the Japanese style plane irons, when they sharpen them, many will go with the blade sideways on the stone rather than square across. I tried that once or twice, and it seems more simple. Add to this, the reason for jigs, is that there are many who are not doing it for a profession, but as a hobby. Freehand sharpening takes some practice, and developing a 'feel' for the edge being flat on the stone. Not every one can do that. Probably why most will sharpen their lathe tools in jigs...

robo hippy

[Cameron Wood]

I take your points about feedback, etc., but from what I see, folks just love to spend money on expensive, complicated gizmos.

[Richard Hutchings]

Not for me, I never owned a whetstone. For me I think it's more about easily maintaining the angle I want and faster sharpening because I don't lift up and reset for every stroke. The guide takes care of that. Before the guide, I sometimes got the angle too steep, I'm not sure. Maybe I needed to practice freehand more but I don't need to practice or feel anything with these guides. I love the results I get. Consistent and sharp, what more do I need.

[Edward Weber]

Feedback is often confusing, too many want to convince you their way is the best method.
I personally prefer using quality jigs.
Whether using a platform or jig for sharpening lathe tools at the grinder or using my MKII for sharpening straight edged tools on a flat surface, I like the consistency that a jig provides.
I use sandpaper on a granite plate, because I don't need/want to maintain oil or water stones.
I can sharpen freehand but choose not to. Just like I can mortise out a piece of timber with a chisel but a mortising machine gets me precise, straight sided mortises every time. A balance of time and ease of work, everyone has their own method.
I also have edged tools that there really aren't any jigs for, so I have to hand sharpen, not a big deal.
Sharpening is a simple concept and most want to make it far too complicate with their methods. At the end of the day, you just do what works for you.

[Jimmy Harris]

Not for me, I never owned a whetstone. For me I think it's more about easily maintaining the angle I want and faster sharpening because I don't lift up and reset for every stroke. The guide takes care of that. Before the guide, I sometimes got the angle too steep, I'm not sure. Maybe I needed to practice freehand more but I don't need to practice or feel anything with these guides. I love the results I get. Consistent and sharp, what more do I need.

I never lift the blade unless I can tell I've gotten way off my angle, which rarely happens. So there's almost no resetting. Just apply slight pressure on the front stroke and keep the angle but with slightly reduced pressure on the back stroke.

Saying that you're not sure if you got the angle too steep is exactly my point. With a whetstone with good feedback, you'll know instantly. It feels different as you get off your angle. Too steep and you can feel the edge dig into the stone. To shallow and you can feel the change in resistance. If you're perfectly flat, you'll feel it glide smoothly and easily, and it'll want to stay on plane. And using a good whetstone teaches you what to feel for, because it's "louder". Then when you use a whetstone with poor feedback, you can more easily pick up on its subtle cues to stay on your angle.

I'm not trying to convince anyone to change their ways. I'm just exploring my hypothesis that maybe the popularity of jigs is due to the choice of whetstones. Or maybe it's, as Cameron pointed out, it's our fascination with gizmos. I know I'm guilty of owning a few redundant tools because they're technically different.

[Jimmy Harris]

Yeah, I'm far from a pro. I'm not even a serious hobbyist. I mean, I work out of my unheated, un-airconditioned garage. And I could fit all of my woodworking tools in my wife's Miata, except for the bench, of course. So I don't have anywhere near the time spent sharpening plane irons and chisels as most of you here. But I do have lots of experience with sharpening in general, as it's something I've always done. Coming from a farming family, it's just something you're taught at a young age. And while planes and chisels are different from pocketknives and garden shears, there's still a lot of crossover. Though honestly, planes irons and chisels are a lot easier to sharpen because they're so much thicker that you get better feedback.

I'll do the sideways sharpening from time to time, but I find it more difficult, as the feedback isn't as great. It definitely takes more skill. Though it is useful for spreading the working area so you don't wear or dish out the center of your surface too quickly. Then again, I don't do it as often, so that could also be why it's more difficult.

[David Carroll]

I almost never get involved in sharpening threads, every good woodworker I have even known has an opinion on the right way to sharpen and once they achieve some level of mastery, most are convinced that they have the best, or in some cases the only way to sharpen effectively. What seems like it should be a relatively simple task has been analyzed to death and is the subject of endless, often heated debates.

I've been using diamond plates for the past 10 years or so. Before that it was scary sharp (Automotive papers on glass), before that it was India/Arkansas stones. About the only thing I didn't really seriously try was Water stones.

In terms of feedback, I like the diamond plates, I like how flat they are and that helps with registering the tool to find the angle. I press down on the bevel near the tip, and with plane irons at least, the tool will stand on the bevel so you can see the angle. With chisels the handle is heavier and so you need to support it with your other hand. But you can feel when the bevel is flat against the stone. To me this helps quite a bit. In terms of actual feedback I can feel, especially with the coarser grits, it grinding, less so with the finer grits. I use coarse fine and extra fine on DMTs stones. Then stropping. This gives me an edge that for me is the right balance between sharpness and longevity of edge.

I think folks like the guides, because they are fairly repeatable and very precise. But like all such things after doing it for awhile, you probably wouldn't need it. These days, the only time I ever use a guide is when I am rehabbing an old chisel, or regrinding after a nick or some other mishap.

[Tom M King]

https://qph.cf2.quoracdn.net/main-qimg-3e93ae80d18c50d4073d8bfae88f14f2-lq

[Rafael Herrera]

If can call anything "feedback" from a sharpening stone, it is its grinding action. I don't know how the angle a which you're holding the tool would be sensed through the stone under normal circumstances.

If you've managed to create a large flat bevel, perhaps you can tell when you're not making full contact, that's unrelated to the quality of the stone, though. Also, single bevel sharpening is not a universal style.

Rafael

[Edward Weber]

If you don't understand the audible, visual and tactile feedback you get from the tool when sharpening, you probably shouldn't be.
Every method provides feedback, even jig based solutions. How you interpret what information you're getting is the key. Once you understand, you probably won't need to spend lots of time and money on sharpening.
JMO

[Rafael Herrera]

If you are referring to me, the OP said "tell you if your angle is off by just a slight amount". I still can't imagine how the quality of the stone can reveal that to you.

[mike stenson]

What do you sharpen with, without a whetstone?

[Rafael Herrera]

I use different media. Mainly a washita stone and a strop. When necessary, I use a guide, bench grinder, crystolon, India, diamond stone, or sandpaper. I don't use water stones.

[mike stenson]

Ahhhh yea, whet means "to sharpen", it doesn't indicate a water stone. I grew up with all whetstones being oil stones. I moved to water stones, because they cut so much faster.

I like a jig on small blades that I can't otherwise get good registration with.

[Cameron Wood]

I got this in the 1980s, and used it so much that the roller wore down to where the nuts holding the roller hit the stone.

Don't use it much lately- maybe I'm getting the hang of sharpening...


508171

[Keegan Shields]

Further complicating the matter - there are far more woodworking tools sold than used. Lots of people buy the jigs and some stones, few end up using them extensively. Even fewer have spent enough time woodworking that they learn to sharpen by hand.

As a rookie, I’ve found that hollow grinding really does help me tell when the angle is off on water stones.

[Richard Hutchings]

Hollow grinding is really the only way to get good feedback on the angle.

[Reed Gray]

For me, it is one of the 'blessing and/or curse' situations. I have to experiment, far more than most. There are very simple solutions some times, and much more complex solutions some times to get to the same place...... I do like a hollow grind to 'simplify' things. I still have not made my mind up about Rob Cosman's '30 seconds to sharp' solution. I can still see 1000 grit scratches. Rob does not use the 30,000 grit Shapton stone any more because he didn't consider it enough of a step up to be worth the effort.

One thing I am curious about, and this does diverge a bit from this thread, but with the Japanese plane irons, do they use a micro bevel? I guess the same question would apply to the bench chisels. I can't remember seeing any one put the micro bevel on that style of plane irons.

robo hippy

[Robert Hazelwood]

Japanese irons and chisels are normally sharpened as one huge flat bevel, but you can sharpen them in whatever way you want as long as the edge angle is appropriate.

For most things I try to hone as small of a bevel as possible, but I do sharpen Japanese tools in the traditional way. Mainly because I like the way it looks, honestly. With that huge bevel you'd think it would be easy to sharpen in terms of keeping the angle correct, but since most of the bevel is soft iron or steel and the tip is super hard, you have to bias all of the pressure towards the tip, to the point you are on the verge of tipping it up and creating a secondary bevel, but not quite. If you don't, the soft iron/steel will wear away faster and the bevel angle will gradually get lower, and then it starts chipping in use. You will also get a lot of unwanted "feedback" if you have much pressure on the soft area of the bevel- it can get very grabby especially with larger irons and with softer stones. Shapton 5k is the worst about this...if you can sharpen a big plane iron on one of those without it grabbing and without tipping it up, then you have just the right pressure.

I normally sharpen everything these days with Arkansas stones, which are very hard and slick, especially the Translucent I finish with. And except for mortice chisels and japanese blades I just sharpen a tiny secondary bevel. I don't hollow grind- I just grind a flat primary bevel at 20 degrees and then a secondary at about 30. Nothing to register on, so you just have to hold it at the right angle. Pretty much like sharpening a pocket knife, except easier because there's no need to flip back and forth and no curve to follow. I suppose I rely on muscle memory mostly, but even with hard stones and a tiny bevel you can steel get a sensation of when the angle is right.

[Jimmy Harris]

For me, it is one of the 'blessing and/or curse' situations. I have to experiment, far more than most. There are very simple solutions some times, and much more complex solutions some times to get to the same place...... I do like a hollow grind to 'simplify' things. I still have not made my mind up about Rob Cosman's '30 seconds to sharp' solution. I can still see 1000 grit scratches. Rob does not use the 30,000 grit Shapton stone any more because he didn't consider it enough of a step up to be worth the effort.

One thing I am curious about, and this does diverge a bit from this thread, but with the Japanese plane irons, do they use a micro bevel? I guess the same question would apply to the bench chisels. I can't remember seeing any one put the micro bevel on that style of plane irons.

robo hippy

Yeah, and the 30,000 grit makes no sense on woodworking tools. You really need something around 62-63 HRC or more to take full advantage of something like 30,000 grit. We use softer steels, because a steel that hard will just chip like crazy, even on soft wood. And the softer steels we do use won't be hard enough to maintain such a sharp point as created by a 30,000 grit stone, nor be able to maintain that sharpness past have a swipe through wood. Probably 6k, maybe 10k is the max you'll want to go. That might even be pushing it. I usually stop at about 3k and sometimes a strop, and that's enough to shave with, which is more than I need for woodworking.

You can use a micro bevel if you want on any blade. There's no right or wrong way to do it. The advantage is it holds an edge longer and reduces the time spent sharpening. The disadvantage is it will eventually require you to regrind your edge. Or, if you sharpen your primary bevel every time along with your secondary, micro bevel, you can avoid having to regrind the edge, but you don't save any time spent sharpening. In fact, you increase your amount of time. Also, a micro bevel, while it holds an edge longer, isn't as sharp as a single bevel.

Personally, I use the single bevel method for most everything. The only thing I put secondary bevels on are mortising chisels, because they take a lot more abuse and benefit from that durability. Everything else, I prefer the increased sharpness of the single bevel. But as long as you're satisfied with the results, then you're doing it right.

[Edward Weber]

Yeah, and the 30,000 grit makes no sense on woodworking tools. You really need something around 62-63 HRC or more to take full advantage of something like 30,000 grit. We use softer steels, because a steel that hard will just chip like crazy, even on soft wood. And the softer steels we do use won't be hard enough to maintain such a sharp point as created by a 30,000 grit stone, nor be able to maintain that sharpness past have a swipe through wood. Probably 6k, maybe 10k is the max you'll want to go. That might even be pushing it. I usually stop at about 3k and sometimes a strop, and that's enough to shave with, which is more than I need for woodworking.

You can use a micro bevel if you want on any blade. There's no right or wrong way to do it. The advantage is it holds an edge longer and reduces the time spent sharpening. The disadvantage is it will eventually require you to regrind your edge. Or, if you sharpen your primary bevel every time along with your secondary, micro bevel, you can avoid having to regrind the edge, but you don't save any time spent sharpening. In fact, you increase your amount of time. Also, a micro bevel, while it holds an edge longer, isn't as sharp as a single bevel.

Personally, I use the single bevel method for most everything. The only thing I put secondary bevels on are mortising chisels, because they take a lot more abuse and benefit from that durability. Everything else, I prefer the increased sharpness of the single bevel. But as long as you're satisfied with the results, then you're doing it right.

This is my approach as well, although I just use a single 30 degree on mortising chisels.


Reed, from what I've read, most do not incorporate a secondary (micro) bevel and rely on a single, sharp bevel. IMO, this is what these blades were designed for, of course others will disagree.

[Paul Koenigs]

I'll never understand why there's such a need to try to convert people to sharpening freehand. I've already bought the jig, it works great, so why not use it? I mean, if sharpening free hand, is your hobby, that's fine, but why the need to put down people that use jigs? My hobby is working wood, not sharpening.

[Russell Nugent]

Because sharpening is like religion. People tend to think their way is the only correct way. Every sharpening thread devolves into that.

[Rafael Herrera]

I fail to see any of the previous posts as trying to convert anybody. That's a new one, free hand sharpening is a hobby, serious hobby woodworkers use honing jigs. I can see some of the pot calling the kettle black attitude there.

[Reed Gray]

I have been pondering the ' no need to go beyond 10000 grit' idea. I have found that with the 16000 grit stone, there is no detectable burr left on my chisels or plane irons.

As for sharpening, I think the saying "ask 10 people the same question and you will get at least a dozen different answers' still holds true....

robo hippy

[Russell Nugent]

A prime example of what I mean. Sometimes this place stinks. Definitely time to leave. No one said what you just did.

[Edward Weber]

A prime example of what I mean. Sometimes this place stinks. Definitely time to leave. No one said what you just did.

Just about everyone who posted in this thread basically said the same thing, do what suits you best.
All anyone can offer is there own experience.
This has been one of, if not the most civil sharpening threads I've read, do ruin it.

[Jimmy Harris]

To everyone: What works for you, works for you. Good enough is indeed, good enough. I'm not trying to convince anyone of anything different. I'm not selling anything, so I have nothing to gain by converting anyone. The whole point of this thread is to think aloud about some of the reasons why we choose the paths we choose. I just wanted to express my thoughts and hear some thoughts of others. You'll never learn anything new if all you ever hear is your own thoughts reflected back at you.


I have been pondering the ' no need to go beyond 10000 grit' idea. I have found that with the 16000 grit stone, there is no detectable burr left on my chisels or plane irons.

As for sharpening, I think the saying "ask 10 people the same question and you will get at least a dozen different answers' still holds true....

robo hippy

The idea is, as some point you're going to get it as sharp as it can possibly be, and going to a higher grit just slows down the removal of material. Too high of a grit will still sharpen, it'll just take longer. It still sharpens though.

Imagine grinding an edge onto a concrete slab. At some point, you're not going to get a pointier edge because you're just going to chip off concrete from the edge you've created. The structure of the concrete will only allow it to get so thin before it's not strong enough to support the act of grinding. Metals are similar, only on a microscopic scale.

Now, I'll often (though not always) strop with that green polishing compound, which is what? 60,000 grit? In theory, it's a waste of time. But my highest normal grit that I use is 3,000. And I definitely notice that I can get it a little bit sharper by jumping to the 60k grit polishing compound. Still, that's a HUGE jump. And in theory, it's both too far of a jump and too high of grit to be effective and efficient. But, it being polishing compound on a soft leather strop, I don't need to perfectly angle the blade, so I can do 30-40 swipes really quickly and get the same edge in the end as I would if I went from 3,000 to 5,000 and then to 10,000 grit with two more stones. And I can probably do it in less time with the strop, and still get to the same edge. So it could be seen a technically wrong, but it works for me. Then again, it might get me to the same spot as a single 8k stone would, and with even more time savings. I haven't experimented with that yet, and don't plan to anytime soon.

The difference between 16k and 10k isn't huge. And depending on the steel, it may actually have a benefit. That PMV-11 steel has a finer crystalline structure, so it'll benefit from a finer grit and hold a finer edge than O-1 or A-2. How much finer? I don't know. And you've got different tempering procedures and stuff, so it can be hard to draw definitive conclusions based on theory alone. Whatever works, works. And you have to factor in the step before your 16k stone. If you're previous stone before that is 12k, then you might not be benefitting from the last stone. You'd have to experiment and see. Or maybe your penultimate stone is a 1k stone. In which case you might be able to save time and still get the same level of sharpness in the end by switching the 16k for a 6k stone, again, depending on the steel. There's a lot of factors to consider, not the least of which is technique, and the only way to know for sure is to try.

These are just theories to consider. They're not hard and fast "rules". Besides, no one is going to look at that table you made and say "wow, your plane iron sharpening skills are beyond reproach!" The process only matters to us. It's only the wood that matters to the world.

[Carl Beckett]

Some things I can sharpen freehand and do a pretty decent job. After learning on various guides (all of which I still have).

Some things I still cant get sharp without a guide. A basic chisel touch up, sure. Resetting the entire angle I still prefer a guide.

Recently I picked up a cheapie Ruixin contraption for kitchen knives. It worked great and my kitchen knives are as sharp as they have ever been (I dont seem to be able to get the same stroke pattern on both sides of a knife - pulling towards me vs pushing away...)

My conclusion is, I am just not that good at it and have not spent enough time mastering the art. And am ok with that.

[David Carroll]

I think there are always people for whom the process (of sharpening, or cutting dovetails, or mortices or many other operations) is as interesting and enjoyable as the product (what is made from the chisels). To each his or her own, I suppose. We are all in this passtime, for different reasons, with different goals. I knew a guy who had all the tools and kept them all sharp and ready, but he rarely made anything. Another guy makes stuff constantly and if you look at his tools you wonder how could this output could be achieved with such a limited kit. Of course between these two extremes you have everybody else. No wonder there is no real consensus.

I do enjoy the threads, (well those that devolve into personal attacks I can live without). I enjoy people sharing their methodology, and how they developed it. I usually learn things. As I mentioned, I use diamond stones mostly for bench planes and chisels. For everything else (carving tools and molding planes) I use India/Arkansas stones and a strop. I have a Tormek system for turning tools and occasional rehab projects, and I have a power stropping setup for touching up the edges of carving tools.

For the work I do I can get any of my tools sharp enough. If I anticipate a difficult cut, I make a special point to get the edge really sharp, a couple swipes on the strop is just right usually. I doubt that my tools would win any competitions for sharpness, but since this is not my goal, it is okay.

But for some guys, getting the sharpest possible edge, or a perfect dovetail, (even on the back corner of a low drawer) IS the goal.

DC

[Edward Weber]

I knew a guy who had all the tools and kept them all sharp and ready, but he rarely made anything. Another guy makes stuff constantly and if you look at his tools you wonder how could this output could be achieved with such a limited kit. Of course between these two extremes you have everybody else. No wonder there is no real consensus.
DC

I know those same people :)

One thing that the OP mentioned that I don't think get enough attention is that certain steels can only achieve/hold a certain edge.
I have chisels of varying quality and while I know some of the higher quality ones will keep an edge longer, I may give them more attention, or sharpen to a better finish. The cheaper tools or inferior steel blades, will never get that sharp, and trying to get them scalpel sharp is just a waste of time IMO.
Most tools dull quickly from their optimum sharpness but keep cutting well for quite a while at the point where their edge is both durable and sharp. Finding this point is different for each steel, bevel angle, and material being cut, this is one reason why there is no consensus.

[Rafael Herrera]

The difference between 16k and 10k isn't huge. And depending on the steel, it may actually have a benefit. That PMV-11 steel has a finer crystalline structure, so it'll benefit from a finer grit and hold a finer edge than O-1 or A-2.

PM-V11 is a proprietary steel, sort of a mysterious steel. Unless someone has measured the grain size and the crystalline structure, who knows what it's actual properties are besides what you get from personal experience.

O1 and cast steel can get very sharp, sharper than PM-V11? I don't know, maybe, I only have a couple of irons in V11 and I don't use them much.

It's been posted before that PM-V11 is actually CTS-XHP or something similar to it. If you want to learn more about this steel, check this link: https://knifesteelnerds.com/2019/07/29/xhp-steel-history-and-properties/

Rafael

[Assaf Oppenheimer]

I use my guide now only for critical angles like in my shoulder plane bladr where square is more than a suggestion, or in super narrow blades like my 1/8 chisel. I like the control.
I use shapton pros and dmt dia sharps followed by strop with green compound. I prefer the diamonds for anything that has the tendency to grove like card scrapers and narrow chisels. Other than that i think the shaptons are probably superior. Of course im lazy so the diamonds get used more so that I don't have such a messy cleanup

[Jim Koepke]

This is about as long as a sharpening thread has gone without going off the rails, amazing.

Just my 508481 on sharpening.

It wasn't until learning with the feedback from water stones that I was able to get decent results from oilstones.

Sometime I find a guide helpful. Most of the time my sharpening is done freehand.

If what you are doing to sharpen a blade is working, then you are doing something right. It is when it isn't working that you have to do the work of figuring out why it isn't working.

That may have been 508482 cents worth.

jtk

[George Yetka]

My thought is they are good for changing your primary bevel. Once the bevel is there I just follow it. It hasnt steered me wrong yet. I have a good veritas one that I purchased before I knew. Havent used since my first or second sharpening. If tommorrow it was discovered that a 45 degree primary bevel was optimal it may be nice to have.