The GREAT sharpening debate

[Kalimna]

What is a scientist other than an obsessive enthusiast who utilises reasoned explanation followed by repeated and repeatable experiment to confirm/deny supposition? And why would he not be a woodworker? Why is the desire to understand a process within definable limits a reason to suspect someone may not be a craftsman?
And I would suggest, Jacob, that you are an obsessive sharpening enthusiast, it is just that the thing you are obsessive about is the ease of the rounded bevel. This is not a bad thing, but it is an obsession

Adam

(just finished 3rd of 4 twelve hour nightshifts, and therefore a little out of kilter!)

 

[Dangermouse]

Hi,

Some people like to understand exactly what is going on, we call them scientists, and they have made every part of our life better, and I would like to thank them.

Pete

Are we comparing research on a cure for cancer , with how sharp a cutting edge can get ????

Also I don't think I can agree with you on them making " every part of our life better" A lot of scientists life's work was and is concerned with how to kill more people quicker and more efficiently or we wouldn't have an arms industry.

 

[Racers]

Hi, Dangemouse

No.

Pete

I would never work in defence/arms.

 

[Dangermouse]

Indeed Pete, I would never work in such an industry too. I dont know how they can sleep at night.

 

[Jacob]

What is a scientist other than an obsessive enthusiast who utilises reasoned explanation followed by repeated and repeatable experiment to confirm/deny supposition?

Not much scientific method in Beech's work IMHO. He charges at it, head down.

....
And I would suggest, Jacob, that you are an obsessive sharpening enthusiast, it is just that the thing you are obsessive about is the ease of the rounded bevel. This is not a bad thing, but it is an obsession

Yes but I don't claim to be a scientist! Actually I'm obsessed by the wider picture i.e. woodwork and hand techniques. It just happens that sharpening is key.

 

[243SS]

......
So, overall, while looking through a microsope can give some interesting information, you should never forget to look at the larger picture.......

Be more interesting if somebody looked at the wood surface with a microscope. The wood gets left out of the equation.

Agree. The tools are secondary, the wood is the most important thing...and even more important, what you do with it.

 

[Jacob]

And his page doesn't work too well e.g. the link to jig design evolution, inviting comments.
So I'll post it here instead.
All the jigs I've seen have the same fundamental design fault - the wheels are behind the edge. They should be in front.

 

[Cheshirechappie]

All the jigs I've seen have the same fundamental design fault - the wheels are behind the edge. They should be in front.

Erm - if you don't mind my asking, why exactly?

 

[Jacob]

All the jigs I've seen have the same fundamental design fault - the wheels are behind the edge. They should be in front.

Erm - if you don't mind my asking, why exactly?

I thought I'd leave it to the team to find out. 8)
NB I've tried it myself with a wooden mock up (no wheels, just wood to stone) and there are a number of very significant advantages.

The 2nd major improvement would be for them to have handles. The fact that they are all so fiddly to hold is basically as stupid as designing any other tool (chisel, saw etc) without a handle.

 

[Racers]

Well if you where only puling the jig backwards wheels at the front would make sense.

As for a handle, most chisels and plane blades are long enough not to need one, and it would probably get in the way.

Pete

 

[Peter T]

I neither know nor care if a rounded bevel is better or worse than a flat bevel.

What I do know is that every time I have tried to sharpen a chisel or plane iron by hand it has ended up less sharp, less square, and more looking like something with which to open paint tins than when I started.

So, if it's all the same to Alfred E Neuman, aka Mr Pooter, I'll stick with my Veritas MkII and DMT plates, with which, in a very few minutes, I can produce lovely sharp, square edges!

 

[graduate_owner]

I bought myself a decent sharpening jig, together with some diamond honing 'stones'. I couldn't believe the difference when I tried using my planes after proper sharpening. I'd always thought there was some secret black art to planing, with the plane juddering and tearing out grain, and so my planes tended to stay in the cupboard. Now my planes glide over wood with a whisper. Similarly all my wood chisels had to be used with a mallet, else they wouldn't cut. I simply had never realised how blunt my tools were, never having had access to sharp tools. I had read about testing for sharpness by using a wood chisel to shave the hairs off your arm but I always thought that was showing off.
I sometimes use the scary sharp system (sandpaper) instead of diamond hones, but diamond is my favourite. When it comes to things like Japanese water stones or hard Arkansas stones, I find these a bit expensive so I haven't bought any - perhaps I don't know what I'm missing, but I seem to be getting good results.

I would not like to be without my sharpening kit now.

K

 

[SammyQ]

I am a scientist, though not one that invents devices to terminate one's fellow humans.

The science of a cutting edge has been translated from the Japanese clearly enough to accompany a video on-line, a beautifully shot video, considering the technology of the time it was created. It delves quite unambiguously into chip formation and edges etc and I thoroughly recommend we all adjourn to find it and watch it and (to paraphrase Monty Python) have less 'waving one's private - sharpening - parts in each other's faces...'

And finally, as my old mentor Lennie Callan said of Hassleblad envy when all I could afford was a Zenith E....."It's not what you have, it's how you use it".

Sam

 

[Dangermouse]

But Sam it wouldn't be half as much fun if we all agreed about this sharpening lark. It makes for delicious debate and conjecture and pontificating and such stuff. :wink:

 

[Cheshirechappie]

When I started out, I tried a jig - the old Eclipse one (still got it, somewhere). I didn't get on with it. It was too much of a faff setting it up to give just the right angle, and it kept falling off the tail end of the oilstone. So I ditched it, and tried freehand. It took me a while to work out how to hold chisels and plane irons so that I didn't dub the edge, and it took longer to realise that even a fine oilstone won't give the ultimate edge (though it does give one good enough for roughing-out and chopping duties).

So I tried waterstones, freehanding again. Worked a treat, and results improved steadily with practice. Buying a small Tormek helped as well; now, the bulk of the metal removal could be done fairly quickly (though jig setting is still a bit of a faff). Honing was then just a matter of a few strokes on medium and fine wasterstones, with finishing on an extra-fine for edges that really needed to be super-sharp. With about six month's (hobby time) practice, I had no difficulty getting arm-hair-shaving edges freehand.

Following a house move, the mess of the waterstones, and the need for a seperate area in the workshop for sharpening, were no longer a viable option, so I bought a medium ceramic stone, and immediately took to it. I supplemented it with an ultra-fine stone, and between the two, get just as good results as I used to with the waterstones, freehanding again. So that's where I'm at now - medium and ultra-fine ceramic stones, used with a small squirt or two of water with a drop of washing-up liquid in, freehand on the bench. Gross metal removal is still by Tormek if I've got a batch of tools to do, or by hand-crank grinder if I can't be bothered getting the Tormek out and setting it up/cleaning up afterwards (it is a messy little beast).

If you prefer using a jig, and the results work for you, then you've cracked the sharpening problem. It just didn't suit me, for some reason. Freehanding did, though it did take practice to get consistently decent results. I notice several people say that they couldn't get on with freehanding, and use jigs. That just proves that different things work for different people.

One thing I would question is the need for an ultimate edge in all cases. For finish carving, for a smoothing plane on final finishing duties, and for end-grain paring where a good finish is needed, you do need VERY sharp tools. For roughing out duties, heavy chopping and the like, an edge off a medium stone will serve perfectly well, so there's no need to spend time and effort on a arm-hair-shaving edge. Judging when to stop sharpening and start cutting wood is just another of the skills that come with a bit of practice.

So the scientific approach is bunkum? Certainly not! Knowledge is power, and even if we don't need to apply every last detail, at least we now know more about it than we did before. Good craftsmen never stop learning, and are secure enough in their craft to know that they'll never know it all, and there are more ways than one to achieve almost anything.

 

[Jacob]

......
So the scientific approach is bunkum? Certainly not! ......

I agree.
But our Brent lacks scientific objectivity in spite of the vast amount of info he has generated. The info creates a fog of pseudo science which can take in the unwary - 'blinding with science'.
Also he makes everything seem so difficult. Not least because he totally rejects free-hand work with a number of very uninformed sweeping statements. Just because he can't do it doesn't mean that nobody else can!

PS a scientific approach would involve blind testing various set-ups in a real woodworking scenario and comparing the results. Some completely forget what sharpening is for.

 

[woodbrains]

Hello,

A couple of observations; there is nothing necessarily 'scientific' about blind testing, unless, perhaps you are experimenting with telepathy or taste testing colas. It is perfectly feasible and acceptable for the 'experimenter' to objectively appraise the results, providing the tests are repeatable and the results consistent. The authour's thoroughness leaves me in no doubt that his results are what they say they are, e.g. an edge is sharper with one method than another. We do not have to do woodwork to confirm sharpness, as visual analysis is justifyably conclusive. It is reasonable that we can conclude that woodwork can only be improved with sharper edges than dull ones, it is axiomatic.

I don't think the authour is against freehand sharpening, or any other method; he developed his jig for his preferences and to give repeatability to his tests. He says, in fact, that he considers the human body as a honing jig, with locked wrists, elbows and a repetable method, just as any mechanical honing device. His only caveat is that the jig must be capable of sharpening the bevel and back of the blade to a high enough degree. If it can be done freehand then fine. For repetabilty, however, I think some mechanical device is essential, or scientific analysis would go out of the window. This does not mean the result have to be acheived this way in a real world situation, where we can take the conclusions and do with them what we will. Though not ignor them, which would be a bit silly, we would have to have a reason not to adopt them. i.e. if he told us the fastest way to get the sharpest edge was 'X' and gave clear proof this was the case, we could not say he was talking nonsence, just because we 'felt' he was wrong, or just wanted to carry on with the method we always use. We would have to agree, but justify doing something different. Method 'X' will give a superior edge, but is too expensive, of the site joiery job I'm doing would have nothing to gain from it. What we cannot say is that the findings are bunkam, unless we can prove otherwise, with the same rigour of repeatabilty and objectivity.

I don't see any reason to doubt that a sharper edge is superior and longer lasting, as it is something I have observed during many years of woodworking. The reasons why (at least in part) have only been conjecture, as I have not done such thorough scientific analysis as the authour. Does knowing that finer abrasives fracture the steel at a molcular level less than coarse ones, imparting greater longevity to the edge. For me, yes; I like to know why I do something that works, even if before it worked when I was ignorant.

Mike.

 

[Jacob]

........ We do not have to do woodwork to confirm sharpness,

Yes you do. "Sharpness" means nothing out of context.

as visual analysis is justifyably conclusive.

No it isn't. You have to prove that your visual analysis does relate to practical use.

 

[Kalimna]

Jacob - Sharpness itself could very easily be deifned without any reference to intended use as the granularity/continuousness (?sp?) of an edge, itself defined as the interface between 2 planes. Context is quite unimportant, for instance micro scalpels used in eye surgery are exquisitely sharp (considerably more so than the edge tools used against wood) but utterly useless for woodwork!. Now, useful/efficient sharpness is perhaps a different matter.

Adam

 

[Dodge]

I started sharpening chisels at the tender age of 8 when i used to get left with my cabinet maker grandfather, in those days if I didn't have a broom in my hand I was sharpening his chisels and plane irons for him and can still hear him saying:-

"Remember boy, if you can see the edge - it isn't there!"

I remember those days with real fondness, I owe so much to my grandfather as his workshop was like an Aladdins cave and he was happy to spend so much of his time passing on his experience.