Sharpening removes too much metal?

[Daniel Rode]

I've read a few replies that seem to indicate that sharpening with <insert method> will remove more metal from the chisel or iron. The idea being that over time the iron would become consumer faster with one versus another.

For example, working the entire bevel each time for a convex bevel edge or a flat single edge would remove more metal versus a primary/secondary sharpening.

Assuming that the angles are kept constant I cannot fathom how a dual bevel sharpening removes any less metal over over time. For convex bevel and single edges, the same amount of metal is removed each time. So the iron's life (length) would be shortened by a fixed amount each time. The dual bevel method would need to remove exactly the same amount of material off the length but the primary bevel would only move every few sharpenings when it's re-ground to reduce the width of the micro bevel.

If any method prematurely shortens the life of an iron, it would be the tri-bevel method. The reason being that with every re-sharpening the tertiary bevel is removed entirely and then re-formed. Even so, over many years the difference is probably trivial. In fact, so little metal is removed with each sharpening that they are all trivial. It takes many, many years of constant work to use up a chisel or a plane iron.

Now wear and tear on sharpening stones is another matter, entirely. The fine stones are going to wear much faster with a convex of single bevel.

Am I wrong?

[Judson Green]

I don't get it either, It would seem to me that all methods would equally remove about the same amount of metal.

[Bill White]

I get numb with all the blah, blah about sharpening. Tools which need to be sharpened will eventually wear. So what?
Ya wanna save tool steel or work with sharp tooling?
I can't EVEN imagine a blahlala stone that will allow me to split microns, cells, etc.
Get 'em as sharp as ya need and go to work.
I don't think that the guys who made some of the antiques in our home worried about a bunch of foolishness.
Sorry if I sound crass, but that's the way I work.
Bill

[David Weaver]

None of the methods remove metal any faster than any of the other methods if all you do is remove the wear plus a narrow margin for security so you don't have to sharpen a second time.

A method that leaves a chisel or iron failing from wear only (and not chipping) will be easier on an edge.

The three bevel method doesn't consume any more than any other method since you're removing the wear with the secondary angle (and not the primary) and the tertiary bevel is only a slight bias to polish the second with only a few strokes.

Some of the comments about preserving irons come from people like me who get infatuated with some irons that are several hundred years old, and we want to remove the wear plus as little as possible after that. If you get a modern iron, or modern chisels, you can go willy nilly with them because there's nothing you can't just buy more of.

[David Weaver]

I don't think that the guys who made some of the antiques in our home worried about a bunch of foolishness.
Sorry if I sound crass, but that's the way I work.
Bill

I would imagine that the guys who did the fine work (especially the trade carvers) were well versed in the various stones (and polishing compounds) and what it would take for them to get very sharp tools.

But for most of what we do, I agree. Sharpening discussions satisfy curiosity and not need. There are plenty of people who don't have any experience, though, and thus the talk about sharpening.

[Matthew N. Masail]

I have a friend who builds beautiful Classical guitars, he just finished one in highly figured birds-eye maple, which is my favorite to play so far. he has a single king 800\4000 combo stone, and dosen't know what angle his plane iron are at. he does really fine work.

[Zach Dillinger]

I would imagine that the guys who did the fine work (especially the trade carvers) were well versed in the various stones (and polishing compounds) and what it would take for them to get very sharp tools.
.

No doubt. And I would speculate that what they knew about getting sharp tools was taught to them by the person who taught them the trade, i.e. "you will use this stone in this manner at this time to sharpen tools while you work for me". They weren't bombarded by 74 different systems, techniques, and teachers.

[Daniel Rode]

An artist might want to discuss composition and light with Michelangelo but he may want to discuss making brushes and grinding pigment. Both were important to him.

I get numb with all the blah, blah about sharpening. Tools which need to be sharpened will eventually wear. So what?
Ya wanna save tool steel or work with sharp tooling?
I can't EVEN imagine a blahlala stone that will allow me to split microns, cells, etc.
Get 'em as sharp as ya need and go to work.
I don't think that the guys who made some of the antiques in our home worried about a bunch of foolishness.
Sorry if I sound crass, but that's the way I work.
Bill

[David Weaver]

No doubt. And I would speculate that what they knew about getting sharp tools was taught to them by the person who taught them the trade, i.e. "you will use this stone in this manner at this time to sharpen tools while you work for me". They weren't bombarded by 74 different systems, techniques, and teachers.

I wonder who brought their wares to them in those days. Some guy in a wagon? because there was no shortage of material describing the virtues of the different polishing compounds, stones, etc.

Presume that the apprentice used the masters stones, and if he wanted to do something different, TS, it would mean trying to figure out what you'd to do be able to eat.​

[Mike Brady]

Any method preceded by a wheel grinder is going to remove more metal than stone lapping alone. I personally would not use a grinding wheel on anything but a coarse tool such as an axe. Certainly not on a plane or chisel. I also dislike concave bevels.

[Malcolm Schweizer]

My name is Malcolm Schweizer, and I am a sharpaholic. I stay up late reading about bevel edges, microns, and honing jigs. I watch videos about sharpening. I look at sharpened edges under magnification. My family has suffered because of my addiction. My friends are slowly leaving me because all I do is talk about sharpening. We go to dinner at a friend's house and I ask if I can sharpen their knives, and then I'm talking microns, diamond paste, and stropping. It's a sickness. I tried rehab. They took all my stones away and forced me to work with dull tools. I didn't last. I had to run out and get a set of Shaptons. Now I am on the streets again, begging for things to sharpen.

Forgive the humor, but seriously- Sharpening for me is a hobby (crazy as it may sound), so I enjoy talking about sharpening methods. It all started as a kid- my uncle from Switzerland would bring us Swiss Army knives, and my grandfather (an amazing woodworker) showed us how to properly sharpen, thus starting a competition with my brothers to see who could sharpen the best. I do, however, think we sometimes get on tangents talking about sharpening and perhaps scare away people who don't understand why. A good reality check is welcome. In the end if you can get an edge fine enough to leave a good finish without tear-out, then you're OK- whatever method you choose. As you grow your skill, your definition of "good finish" gets more refined. Who was it that posted the image recently of the amazing fine finish on a piece of planed wood? Sorry that I can't give proper credit, but you could look at that image and appreciate what a well-honed edge can do for a piece. Now that I have reached a much higher level in my work, I pay a lot more attention to sharpening my tools.

My name is Malcolm Schweizer, and I am a sharpaholic.

[Jerry Thompson]

I have all but trying all of the methods posted, ad nauseaum, I just grab a stone or two depending on what I need to do and have at it free hand. I get whisper shavings if needed or thicker ones when preparing a thicker board. I used to anguish over getting it all just as a post had described. If it works it works is the bottom line.

[ian maybury]

I guess the presumption is that grinding (because it rapidly shifts material) is going to tend to remove more material than is absolutely necessary - while honing on a stone only removes what's needed to get an edge. Hence the rationale that re-grinding the primary bevels as in infrequently as possible/restoring the edge by honing as often as possible between grindings saves wearing the tool out too quickly.

My background is engineering, and hence my response is predictable Bill - and my apologies if the sharpening theads bore the tail off those of you doing it for years. I have to say though that i find it hugely useful to hear people discuss sharpening in technical/analytic terms. It means I can without anybody local to teach me (the skills are rare here) figure out what we're trying to achieve, and with relatively little trial and error make it happen. I likewise try to make a point of reporting my experience - on the basis that there are probably lots where I was.

It doesn't have to be done that way - an experienced tradesman using methods that work can simply pass on what he does - but the problem with that is that there's a tendency for a lot of hocus pocus/magic/rote thinking to creep in. The old you have to do this, this, this and this, and then rub it with the hair of a tomcat type stuff.

It's a very fundamental principle in industry - that it helps to explicitly de-mystify, explain and define processes in technical/numbers/systems terms. The problem is that if this is not done a mythology tends to grow up around certain jobs, and those with the skills tend to not share the information to strengthen their own position. Plus when the process is not quantitatively specified troubleshooting and improvement is much more difficult and less reliable - because it's not possible to measure and check out the variables to determine whether its properly set up or not.

It can go the other way of course - that people end up paralysed by or are unable to handle the resulting complexity...

Japanese waterstones are a case in point. I'm blown away by the way they make achieving incredible edges so easy, but if it wasn't for the likes of David Charlesworth pontificating away in the magazines about ten years ago about how he did it (and he's taken flak for being too technical) I'd simply never have known the possibility existed. The guy with the wagon around here when I was growing up only ever had ropy old carborundum stones and oilstones - and very few really knew how to get the best out of even them. Likewise on set up of hand tools....

[ray hampton]

Any method preceded by a wheel grinder is going to remove more metal than stone lapping alone. I personally would not use a grinding wheel on anything but a coarse tool such as an axe. Certainly not on a plane or chisel. I also dislike concave bevels.

if you use a axe from dawn to dusk , you will not use a grinding wheel unless you got a slave to pack it into the forest, a file weigh much less

[Derek Cohen]

Any method preceded by a wheel grinder is going to remove more metal than stone lapping alone. I personally would not use a grinding wheel on anything but a coarse tool such as an axe. Certainly not on a plane or chisel. I also dislike concave bevels.

I think that this misconception is at the heart of the OPs original post.

A grinding wheel removes steel from the centre of the bevel face to create a hollow. A high speed grinder does not reach the end of the bevel and, therefore, does not remove any steel from the length of a blade. A Tormek may or may not grind to the edge. In the case where it does grind to the edge, the fine wire created is about the same as raising a wire edge with a coarse waterstone.

The grinding method that will remove length is where one works on the flat face, either with a belt sander or coarse stone, and then adds a secondary bevel. In any even, it is not grinding, per se, that creates the most wear - it is grinding that goes past a fine wire edge.

Even then, wear is measured in microns and will take many, many years to create an appreciable reduction in blade length.

I'd rather have sharp blades, so do not worry about the length. Consider modern blades to be consumables.

Regards from Perth

Derek