are there any decent techniques for squaring a chisel blade?

[G S Haydon]

Although a convex bevel is a method that works all western text I have read says nothing about convex bevels of any kind, if anything they must be avoided. Can't comment on Japanese text though although the single flat bevel seems to ring true. That's not a diss as many find the convex bevel to be very satisfactory, just an observation from the books I have.

 

[Cheshirechappie]

This last one isn't a dig at anyone, merely an observation, I wonder if hollowed stones came about because old craftsmen just didn't care about that kind of minutae and just got on with the job in hand or whether there was a logical reason behind it? Does anyone think we're now in an age where we could actually over analyse things?

What we haven't had is a discussion of why different stones are used, that would probably go some way to explaining why people prefer them over others? For instance, weren't all the good natural stones disappearing, so other sharpening mediums became popular alternatives? and with those different mediums came different ways of caring for them?

I'm not sure that there's any 'right' answer to how hollowed stones came about, but a couple of thoughts that occur are these - some people are naturally more meticulous than others, and conditions of work vary for different woodworkers. For example, a millright or carpenter engaged in heavy construction work such as centering for masonry arches would need heavy tools used with a big mallet, in fairly rough working conditions, and possibly without easy access to a grindstone. So, a convex bevel and hollow stones fit the circumstances. A fine cabinetmaker or patternmaker in a well-equipped workshop may have different attitudes to tools and stones. Human nature varies too - some joiners may have been quite happy with one sort bevel, some with others. Hence the variation in the condition of old tools and stones.

On stone types, until the late 19th century, only natural stones were available. In the UK, that tended to be Turkey (imported), Charnley Forest (indigenous), Welsh Slate and a few others (Tam O'Shanter, Water of Ayr, for example). They tended to be slow cutting, and being natural, their properties could vary a bit from stone to stone. When man-made stones (Norton India and Washita) started to become available, many craftsmen switched because the new stones were in general faster cutting and generally more consistent in their qualities (Walter Rose documents this in 'The Village Carpenter'). Now, of course, we have even more options available, some of which do better in some circumstances than others - some of the modern alloy tool steels cut better on some types of stone than on others, for example.

There's a lot more highways and byways to sharpening stone history than that, of course; a googling session would no doubt throw up all sorts of info.

 

[Jacob]

.... I wonder if hollowed stones came about because old craftsmen just didn't care about that kind of minutae and just got on with the job in hand or whether there was a logical reason behind it?

Hollow stones came about because people used them for sharpening. No need to look further! Efforts would be made to keep them flat as far as necessary, but it wasn't essential until the advent of the honing jig - at least, for those who became dependant on them

Does anyone think we're now in an age where we could actually over analyse things?

Yes definitely. Brent Beach is yer man! Leader of the pack!
"Fine" woodworkers also would have hollow (ish) stones and convex bevels if they chose - there is no particular disadvantage - it's not just rufty tufty joiners, who know no better!

 

[woodbrains]

Hello,

The Japanese sharpen planes and chisels with a FLAT SINGLE bevel. Their tools need support from the softer steel back, or jigane to work properly. Anything but flat reduces the amount of jigane behind the cutting edge and is not done. It is an almost religious ritual for correct tool preparation of traditional Japanese hand tools, and doing anything else is wrong, and there is definitely right and wrong in Japanese tool use and care, unlike us Westerners, who are allowed a lot of latitude.

Mike.

 

[Phil Pascoe]

Cheshirechappie - Washita is a natural stone.

 

[Jacob]

Hello,

The Japanese sharpen planes and chisels with a FLAT SINGLE bevel. Their tools need support from the softer steel back, or jigane to work properly. Anything but flat reduces the amount of jigane behind the cutting edge and is not done. It is an almost religious ritual for correct tool preparation of traditional Japanese hand tools, and doing anything else is wrong, and there is definitely right and wrong in Japanese tool use and care, unlike us Westerners, who are allowed a lot of latitude.

Mike.

There may well be those who impose an arbitrary rule on themselves, much in the same way as people do here. The Japanese have a tea ceremony but they also drink tea in a non ceremonial way. The few Jap chisels I've seen in use (Japanese woodworker doing a demo) and a few I've spotted on the web - had rounded bevels. In fact one was posted up here with the poster complaining that it had been sharpened "wrongly".
So I don't believe that they all follow a rule. I'm not even sure that there is one, let alone that it is commonplace.
These rules, once voiced, seem to have a life of their own and hang around forever like a virus.
"Westerners, who are allowed a lot of latitude" is an odd phrase. Who does the "allowing"?

One thing is certain - it wouldn't make a haporth of difference to the woodwork either way and the burbling about "jiganes" is nonsense!

PS looking for jigane http://www.nihontocraft.com/nihonto_general_terms.html what is it?
PPS Found it http://www.samuraisword.com/glossary/index.htm it means "sword steel".

 

[bugbear]

PS water stones seem to be a Japanese concept, but they do do convex bevels and they don't use sharpening jigs. Why is this?

Normal Japanese practise is single flat bevel. Some Japanese use jigs.

BugBear

How do you know this? Jap convex bevels have been commented upon many times and there is no Japanese honing jig. In fact the honing jig was unknown to woodwork universally and is only a fairly recent novelty on the amateur woodwork scene.

I can recommend Japanese Woodworking Tools: Their Tradition, Spirit and Use, by Toshio Odate as a easy to read introduction, if you want to underrstand some Japanese technique.

BugBear

 

[Graham Orm]

I've seen several video's of Japanese woodworkers, but never any of them sharpening. I would be interested to see one if anyone has a link?

EDIT: Here we go http://www.youtube.com/watch?v=Hv4mOMiRKyQ

EDIT 2: Don't hold your breath, no rocket science, just a bloke sharpening his chisels.

 

[Jacob]

......

Normal Japanese practise is single flat bevel. Some Japanese use jigs.

BugBear

How do you know this? Jap convex bevels have been commented upon many times and there is no Japanese honing jig. In fact the honing jig was unknown to woodwork universally and is only a fairly recent novelty on the amateur woodwork scene.

I can recommend Japanese Woodworking Tools: Their Tradition, Spirit and Use, by Toshio Odate as a easy to read introduction, if you want to underrstand some Japanese technique.

BugBear

Got it. He's fairly conventional about sharpening. Certainly not committed to "correctness" woodbrain style!
No jigs of course.

 

[bugbear]

Got it. He's fairly conventional about sharpening. Certainly not committed to "correctness" woodbrain style!
No jigs of course.

I hesitate to ask, but could you explain what you mean by conventional?

The low bevel angle and thick blade of Japanese tools makes sitting them on the consequent large flat bevel easy to do without jigs - tool design and technique form an integrated whole.

Despite this, even competitors at Japanese planing contests(*) have been seen using sharpening jigs, some commercial, some of their own making.

BugBear

(*) judged on the shavings - you wouldn't like them :lol:

 

[Jacob]

Got it. He's fairly conventional about sharpening. Certainly not committed to "correctness" woodbrain style!
No jigs of course.

I hesitate to ask, but could you explain what you mean by conventional?

Flat bevel good, rounded over bevel bad, two bevels perhaps not good, hollow ground bad. Nothing I would disagree with, though he doesn't say anything about convex rounding under, which I expect is a default condition of most hand honed plane and chisel blades, there as here, as it's easier and works. Easier in that attempting a dead flat bevel by hand held honing is really quite difficult, but pointless anyway.

The low bevel angle and thick blade of Japanese tools makes sitting them on the consequent large flat bevel easy to do without jigs - tool design and technique form an integrated whole.

Easy to do a thin blade without a jig. You hold it at the desired angle. Simple. I know many modern amateur woodworkers believe this to be impossible - but they are wrong.

Despite this, even competitors at Japanese planing contests(*) have been seen using sharpening jigs, some commercial, some of their own making.

But not commonplace or traditional - though small blade holding devices are (here and there) - usually just a saw kerf in a bit of scrap. Odate has a more refined one with a wedge.
These stupid expensive gadgets here aren't Japanese!

 

[woodbrains]

I've seen several video's of Japanese woodworkers, but never any of them sharpening. I would be interested to see one if anyone has a link?

EDIT: Here we go http://www.youtube.com/watch?v=Hv4mOMiRKyQ

EDIT 2: Don't hold your breath, no rocket science, just a bloke sharpening his chisels.

Hello,

Notice in this video, how the craftsman skews the chisel to maintain a flat bevel. There is little or no danger of the chisel being lifted and lowered at the end and start of the stroke, by doing so. I have even seen advice that the chisel may be presented at 90 degrees to the stone, to eliminate any rocking whatsoever. Incidentally, a technique I have used for years when sharpening freehand.

Since Japanese chisels are made by blacksmiths who take much time and skill to forge weld a wrought iron back to the very hard face, to give it support, why would anyone in their right mind, undermine this by not maintaining a flat bevel. The chisel will fail if you don't. It is the chisel's very construction that dictates the proper way to sharpen, it is not a matter of opinion.

There is probably more nonsense on the web than real fact. We have to use some sort of filtering system to weed out the dross from the truth, so finding contrary information does not make it true. Finding such misinformation and then using it to justify ones own methods would make that person a fool, wouldn't it?

Mike.

 

[Cheshirechappie]

Cheshirechappie - Washita is a natural stone.

Phil - thank you, you're absolutely right.

According to Walter Rose in 'The Village Carpenter', the natural Washita stone was introduced to Britain in 1889, and almost immediately superceded the Charnley Forest stones then in use. Later, Norton 'India' and Carborundum man-made stones became available, in several grades, thus giving the woodworkers of the day far more choice and the ability to 'get an edge' far quicker than they had been able to with indigenous natural stones.

As an aside, Rose also mentions that he prefers a narrow stone for sharpening wide plane irons. He had a 1 3/4", and would not entertain a 2". The reason he gave is that it tends to avoid hollowing of the middle of the stone, as there is a tendency to use the middle of wider stones to sharpen narrower tools.

That's not to say that Rose's preference was followed by all craftsmen of his day, but it is the documented practice of one particular craftsman. Interesting, but not necessarily conclusive proof of general practice at the time.

 

[bugbear]

Flat bevel good, rounded over bevel bad, two bevels perhaps not good, hollow ground bad. Nothing I would disagree with, though he doesn't say anything about convex rounding under

Of course not - it's the same as rounded over.

If a round bevel is 30 at the edge and 25 at the arris, it matters not at all if the honing stroke is starts at 25 and ends at 30 (rounding over) or starts at 30 and ends at 25 (rounding under). They both produce the same result. I've never heard anyone but you make the distinction.

Edit; I think I've found a minor tradition of people showing just how perfect their flat stones and bevels are; so perfect that capilliary action alone will stick the blade to the stone.

BugBear

 

[bugbear]

there is no Japanese honing jig.

http://www.arde.co.jp/item/1124GKT-100/

http://www.arde.co.jp/item/1124GKT-100B/

There are more things in heaven and earth, Horatio,
Than are dreamt of in your philosophy.

(I found out how to google in Japanese )

BugBear

 

[woodbrains]

=D>

there is no Japanese honing jig.

There are more things in heaven and earth, Horatio,
Than are dreamt of in your philosophy.

=D> =D> =D> =D>

Or is that an eccentric cam at the back for producing convex bevels? :twisted:

Mike.

 

[Jacob]

Flat bevel good, rounded over bevel bad, two bevels perhaps not good, hollow ground bad. Nothing I would disagree with, though he doesn't say anything about convex rounding under

Of course not - it's the same as rounded over.

If a round bevel is 30 at the edge and 25 at the arris, it matters not at all if the honing stroke is starts at 25 and ends at 30 (rounding over) or starts at 30 and ends at 25 (rounding under). They both produce the same result. I've never heard anyone but you make the distinction.

It isn't the same.
Rounding over is the deprecated process where to get a burr quickly the handle/blade is lifted a touch to increase the honing angle above (over) the desired 30º (or whatever). OK once or twice but eventually will have to be taken back to 30º
Rounding under (as I have taken to calling it) is the opposite - the handle/blade is dipped to an angle below (under) 30º as you go forwards and maintains the edge angle at 30º but takes metal off the back of the bevel instead.
I'm sure you will get it one day BB!

 

[Jacob]

=D>

there is no Japanese honing jig.

There are more things in heaven and earth, Horatio,
Than are dreamt of in your philosophy.

=D> =D> =D> =D>

Or is that an eccentric cam at the back for producing convex bevels? :twisted:

Mike.

No it's a little oddity. Blade holders are common (essential for honing a small blade) but jigs are not (in Japan) and virtually never get a mention. The thing you show wouldn't last long at all in routine use.

 

[bugbear]

Flat bevel good, rounded over bevel bad, two bevels perhaps not good, hollow ground bad. Nothing I would disagree with, though he doesn't say anything about convex rounding under

Of course not - it's the same as rounded over.

If a round bevel is 30 at the edge and 25 at the arris, it matters not at all if the honing stroke is starts at 25 and ends at 30 (rounding over) or starts at 30 and ends at 25 (rounding under). They both produce the same result. I've never heard anyone but you make the distinction.

It isn't the same.
Rounding over is the deprecated process where to get a burr quickly the handle/blade is lifted a touch to increase the honing angle above (over) the desired 30º (or whatever). OK once or twice but eventually will have to be taken back to 30º
Rounding under (as I have taken to calling it) is the opposite - the handle/blade is dipped to an angle below (under) 30º as you go forwards and maintains the edge angle at 30º but takes metal off the back of the bevel instead.
I'm sure you will get it one day BB!

Drop for the arris, raise for the edge, it's one motion run backwards or forwards. I don't "get" the distinction because there's nothing to get. It's just a rounded bevel, made by varying the handle height during the stroke.

BugBear

 

[Harbo]

In "The Jointer and Cabinetmaker" published in 1837, the hollowing of stones was an issue.
It was expected that the Journeymen would leave the stone flat for other users and could be fined for not doing so.
They often paid the Apprentices a penny or two to do it for them.

Rod