# Wasted Steel



## G S Haydon (25 Apr 2015)

I'm opening myself up to look a twerp (nothing new there). 

I've had a brief discussion with Derek about his thoughts on how his present honing method preserves the length of the chisel, plane iron etc more than any other. 

Derek's thoughts 
_"For those with a Tormek or a CBN wheel, it is possible to grind to the edge of the blade. The aim is not to grind away the edge, but just to the edge. You can determine this by feeling for the wire edge. Stop grinding when you feel the finest of burrs. In my case I hone directly on the hollow, and the microbevel so created is coplanar with the primary bevel. In other words, no secondary bevel is formed.

The third method is to use a honing guide and add a secondary bevel. This could be done on a flat or hollow grind. The secondary bevel will shorten the blade more than the other two methods. "_

My feeling is irrespective of sharpening method is that we all need to remove the same amount of wear to refresh the edge. I don't think any method reduces length more than any other apart from over zealous grinding. I can't imagine Japanese woodworkers are reducing their plane irons more quickly by not hollow grinding.

Or am I totally missing something (more than possible).


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## MIGNAL (25 Apr 2015)

At one time I used a similar method with a hand crank. If you were starting from scratch you would grind a primary bevel with 120G on the hand crank, the secondary bevel was formed with a 8,000G waterstone. That's it, nothing between the two grits. When the blade became dull you would continue to use the 8,000G stone. When the secondary bevel became too wide you would revert back to the 120G hand crank and creep up to the very tip of the blade, _without_ going over it though. The only metal being removed from the edge is with the 8,000G or with stropping. 
Now I use the same method but with a coarse Oil or coarse diamond stone. It's the relatively slow removal of material on the primary bevel that allows you to use this technique, it makes for easy control. It's also very easy to differentiate between the coarse grind marks and the polished bevel of the 8,000G stone.
I'll guess but the Sellers method _probably_ removes more metal. The difference must be pretty slight though. Nothing to get worked up about.


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## Cheshirechappie (25 Apr 2015)

G S Haydon":2c2p8zyj said:


> My feeling is irrespective of sharpening method is that we all need to remove the same amount of wear to refresh the edge. I don't think any method reduces length more than any other apart from over zealous grinding.



That's correct. A given amount of wear to the edge will require the same length of tool to be removed to refresh it, irrespective of the method used. Metal removal further up the (primary) bevel will not affect the edge sharpness one bit (it may affect edge strength, but that's a slightly different matter). Thus, using the Paul Sellers rounded bevel technique removes a greater volume of metal at each honing, but removes it from the whole bevel. Using the more common 'secondary bevel' removes much less volume of metal at initial honing after regrinding the primary, but bulk metal is removed when the primary is reground. 

However, provided just enough work is done to restore a good edge each time, the overall rate of metal removal, averaged over a large number of honings, is the same for all methods; and the tool becomes the same amount shorter at each honing no matter what method is used to hone it. 

That applies to flat (Japanese style)bevels, hollow ground bevels, convex bevels or any other bevel - the amount of metal removed, averaged over a large number of resharpenings, is the same for any method, provided just enough work is done to restore the worn edge to working sharpness each time.


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## CStanford (25 Apr 2015)

If you produce a burr at the wheel it will only get larger as you polish out the extraordinarily rough edge left by the grinder. This method uses up steel faster than producing the burr on one's finest or next to finest stone. It uses it up faster because the burr will grow when the edge is polished to rectify the rough edge left by the wheel.

One might like to preserve a favorite chisel or two but beyond that it's all disposable tooling - plane irons for sure. 

I don't care to get on the upgrade path with respect to grinding wheels. The wheel's job 95% of the time is simply to restore the hollow, never grinding to the edge and producing a burr. The other 5% of the time if even that is carefully working out the relatively rare nicks and gouges. I can't imagine there is an advantage to regularly grinding all the way to the edge to produce a burr, the edge would be a very rough one indeed and need further treatment up through the grits right at the cutting edge with is the antithesis of being frugal with steel.


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## G S Haydon (25 Apr 2015)

All I hope is that I have not got the wrong end of the stick regarding Derek's point as it seems you all share my thoughts on this.


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## Biliphuster (25 Apr 2015)

I don't think it makes a difference, a 1mm nick will require the edge to move back 1mm to remove no matter how you do it. The same goes for folded steel, worn steel or any other sharpness malady, the new edge is somewhere in the body of the blade and anyway of removing the excess metal will be equivalent as long as you stop once a new edge is reached.

I do about 90% of my sharpening (full bevel) on my finest stone and I don't think I will ever get even half way down my most used chisel. I had always assumed the very short chisels you sometimes see had an owner who was over fond of the grinder.


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## CStanford (25 Apr 2015)

G S Haydon":33gfxf46 said:


> All I hope is that I have not got the wrong end of the stick regarding Derek's point as it seems you all share my thoughts on this.



I do agree. Grinding to a burr wastes steel. No doubt about it.


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## G S Haydon (25 Apr 2015)

I think so Charles, grinding to a burr is ok if you want but always best to leave a sliver of honed edge left.


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## woodbrains (25 Apr 2015)

G S Haydon":u1xk8ddq said:


> I think so Charles, grinding to a burr is ok if you want but always best to leave a sliver of honed edge left.



Hello,

Absolutely, and this reduces the chances of drawing the temper if using a dry grinder.

The Tormek does not produce a very rough grind, though, so it is OK to grind right to the edge (but no further) and there will be no great loss of steel in the honing stage. There is no real danger of drawing temper, either. I suspect a CBN stone might create a coarser grind.

Mike.


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## Cheshirechappie (25 Apr 2015)

Biliphuster":393xu6rv said:


> I do about 90% of my sharpening (full bevel) on my finest stone and I don't think I will ever get even half way down my most used chisel. I had always assumed the very short chisels you sometimes see had an owner who was over fond of the grinder.



Indeed - or possibly a chisel that has served two or three generations of craftsmen. I doubt many people would wear out a full-length chisel in a lifetime. Plane irons are a different matter, though - a well-used bench plane might consume two or three irons in a craftsman's lifetime.


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## Derek Cohen (Perth Oz) (25 Apr 2015)

Tormek and CBN wheels grind very cool and there is no burning of the steel when you grind to the edge. Further, this does not weaken the steel. I have never experienced a failure as a result of a hollow ground edge.

Now what Graham has not explained is that I am not advocating grinding over the edge, but _to_ the edge. This becomes apparent when you create the very finest of wire edges - indeed the type of wire edge from 1 or 2 strokes on a 1000 grit waterstone (that is all I need). 

What I wrote:_ "For most, hollow grinding a blade removes waste from the centre of the hollow. The subsequent honing removes the same amount of steel as honing on a flat bevel. All a hollow does is remove the unimportant steel from the equation when honing. Honing here removes the same amount of steel as the next method, but takes longer.

For those with a Tormek or a CBN wheel, it is possible to grind to the edge of the blade. The aim is not to grind away the edge, but just to the edge. You can determine this by feeling for the wire edge. Stop grinding when you feel the finest of burrs. In my case I hone directly on the hollow, and the microbevel so created is coplanar with the primary bevel. In other words, no secondary bevel is formed.

The third method is to use a honing guide and add a secondary bevel. This could be done on a flat or hollow grind. The secondary bevel will shorten the blade more than the other two methods. "_

The question that started the whole debate on SMC was whether a secondary bevel (on either a straight or hollow grind) shortens the blade more than honing a coplanar bevel on a hollow grind. My position was that the secondary bevel (a bevel with a higher angle to the primary bevel) shortens the steel fastest.

Why do I hone as close to the edge as possible? Simply because it takes less time and effort to hone, and there is less need for grinding thereafter. Ironically, to grind this close - and end up grinding less - one needs a more expensive set up. 

Regards from Perth

Derek


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## G S Haydon (25 Apr 2015)

Removing the style of honing we may prefer the only aim of honing is to remove wear or damage. That is a fixed distance that any method must travel. And I've not been on the scrumpy Derek, not yet anyway :lol: 

Raising any kind of burr on a grind is waste. I'll freely admit it's not worth worrying about in the slightest but if preserving tool length is important then just leave a sliver in?


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## CStanford (25 Apr 2015)

The hollow only needs to be restored to the extent it will function as a jig for freehand honing. If one hones on the grind then the angle does not grow so there is not need to grind to, or just behind the edge to the extent there is danger of going over. Just put the hollow back in so you can 'click' the unit to the stone and hone. No real need to get exceedingly close if you hone on the grind.

Secondary bevels do use up steel the fastest as Derek points out. 

I've yet to wear a chisel completely down, though I'm pretty close on a quarter inch chisel.


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## MIGNAL (25 Apr 2015)

Why do secondary bevels use up more steel? Why can't you continue to use a secondary bevel and remove _just the wear_ ? which is exactly what you are doing if you use a single bevel.
Surely honing coplanar on a hollow grind is effectively a secondary bevel, No?


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## G S Haydon (25 Apr 2015)

I'm with you here MIGNAL. This has to be a truly original sharpening debate, I don't recall one like it before!

Charles, would you say they shorten the tool faster? For instance bearing in mind all we have to do in the race is remove the red portion of the image and stop how will any method of honing remove more?


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## G S Haydon (25 Apr 2015)

Derek, I think I may have got it.

Firstly this is your favorite method so it has to be based on your method. So in your example grinding means raising a burr before honing again. On the first hone after this "burr grind" you would indeed use little more length on the tool on the first hone only if you lifted for a secondary. After the first hone both hollow hone and secondary then remove the same amount of length as they have to overcome wear/damage

I think because I don't grind to the edge this had me confused. And for those not doing a "burr grind" my original point of all methods remove the same still stands. Do I have it or am I still missing it!


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## CStanford (25 Apr 2015)

On chisels ground and honed higher the wear becomes more rounded and thicker. One usually keeps honing higher and higher at each session in order to produce a burr quickly until the unit finally has to be ground back to work again - the wear is figuratively as thick as your thumb at that point. You have to get all the way back behind the rounded wear that goes too far up the face of the chisel -- you have to take out thickness AND length to get behind it.

More steel behind the edge means more has to come off to get behind the wear.


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## MIGNAL (25 Apr 2015)

But you don't have more steel behind the edge on coplanar and a hollow grind. Nor do you have to hone at a higher and higher angle on a secondary bevel. 
Let's forget trying to get a burr. My newly bought chisel comes to me with a single bevel ground at 25 degrees. Let's say I hone a secondary bevel a few degrees higher using an 8,000 fine stone. I get a polished glint across the entire width of the chisel that has a depth of 0.3 mm's. I use it, it becomes a little blunt. I then take it back to the very fine stone and work on the _secondary bevel only_ until the chisel is sharp. Let's assume that the glint now is at 0.6 mm's depth. I do the same again but this time the glint has grown to 0.9mm's. 
After this I deem that it now takes too long with the very fine stone. I go back to the primary bevel and grind back using a very coarse stone. I take that primary grind to 0.3 mm's (or thereabouts) of the blades edge. I do not take it past the tip. I continue to hone with the very fine stone. 
This is essentially the method that I use. It's really no different to the method that I used before, which was a hollow grind using a hand crank and coplanar hone with an 8,000G waterstone. When the glint became too wide I would take it back to the hand crank and grind _near to_ the tip.
I honestly cannot see the difference. One is a secondary bevel and the other, the coplanar hollow grind is also a secondary bevel but the steel behind the edge on that is a touch thinner.


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## bridger (25 Apr 2015)

For the tools I use and sharpen, the wear bevel on the flat side is usually the thing that determines how much steel needs to be removed. The angle and condition of the final bevel, the one that actually makes the cutting edge, has the most to do with how the tool performs. Everything behind that, whether it is flat grind, hollow grind, convex grind or some multiple of flat bevels is irrelevant. Do the bevel shaping by the method of your choice, using the tools you have, and don't waste good steel, or time spent sharpening.


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## Derek Cohen (Perth Oz) (26 Apr 2015)

I think I have figured it out - this is more about geometry .. and the answer becomes apparent when a missing element is added in. 

Firstly the bottom line: the hollow grind and the secondary bevel remove the same amount of metal. There is a provisor, however. I will come back to this part (keep you in suspense!  ).

What was missing from our computations? Well, the hollow grind was on a bevel face of 30 degrees, and honing would take place on the hollow, with the hollow acting as a jig for the hone. The secondary bevel of 30 degrees would take place on a bevel face of 25 degrees. What was missing is that in both situations the honing is at 30 degrees. One imagines that the 30 degree secondary bevel is removing extra steel, but it is not - it is only removing the steel that would have been ground away if the primary bevel was 30 degrees ...






The orange section in the second figure represents the area of steel ground away from the 25 degree primary bevel that would be present if it were ground to 30 degrees. 

The red lines represent the first hone. This should remove the same amount of steel from both blades _as long as the 30 degree angle is maintained._

The blue lines represent the second hone. Again, this should remove the same amount of steel from both blades _as long as the 30 degree angle is maintained._

Here is the provisor: freehand honing on the hollow grind essentially ensures that the bevel angle is maintained. However, this is not the case for the secondary bevel. Only a honing guide will ensure the angle is kept. When freehanding there is the tendency to increase the angle slightly. Eventually this will remove more steel this way, plus a later regrind to re-establish the angle will use up still more steel. By contrast, removing waste from the hollow does not alter the bevel angle, and ensures that the same amount of steel continues to be removed as always. 

A hollow like this will last a long time ...






Regards from Perth

Derek


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## Cheshirechappie (26 Apr 2015)

I think that post pretty well accords with what everybody else has said, though I'm not sure everybody excluded honing at 30 degrees from their computations.

There's one point I'd beg to differ on. From experience, I know it's perfectly possible to freehand hone and maintain a 30 degree secondary (working edge) bevel accurately enough for all woodworking purposes. Developing that skill takes a little practice, but once you've 'got it' it's ingrained for life. I fully accept that some people prefer to use a honing guide for any number of reasons, and that's fine - do whatever works for you - but to suggest that only a honing guide will keep the angle is bunkum - craftsmen have been 'keeping the angle' freehand for generations. Many still do.


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## MIGNAL (26 Apr 2015)

I freehand the secondary angle. I tend to use very short forward/backward strokes on a very fine stone. My theory states that the greater the arm movement the more chance there is of 'losing' the angle. The figure of 8 seems to be an incredibly complicated form of arm movement, although I've no doubt that some people master it. 
I've no idea how accurate I am with that secondary bevel, at least I don't pay much attention to whether I lose it or not. I simply observe how large the secondary bevel is. I only get 3 or 4 'sharpenings' before I redress the primary bevel but that's not because I'm losing the angle. It's more about having to remove less metal.


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## woodbrains (26 Apr 2015)

Hello,

The geometry just over complicates the issue. As Bridger posted, we need to hone past the wear on the flat side of the tool to achieve sharpness and this requires the same amount of loss of length to the tool no matter what method of honing is used or what angle the bevel is at. 

Being a bit controversial here, but the quickest way, with less steel lost to hone past the wear on the flat side, is to use a back bevel, or ruler trick! (hammer) sorry!

Mike.

Edit, no use for chisels, though just plane irons.


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## G S Haydon (26 Apr 2015)

Thanks for the diagrams Derek. Diagram 2 shows the black line of the grind angle projecting beyond the red first hone. If when we grind we leave in a sliver of hone both methods changes the length by the same amount. I think these diagrams only work if you grind to a burr so to speak?

As mike siad "we need to hone past the wear on the flat side of the tool to achieve sharpness and this requires the same amount of loss of length to the tool no matter what method of honing is used or what angle the bevel is at."


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## Corneel (26 Apr 2015)

All geometry aside, let's have a look at how much steel you need to remove to get beyond all the wear and tear from the edge. I have no idea how a chisel wears. i guess it totally depends on how it is used and a paring chisel has a different wear pattern compared to a mortise chisel.

So let's have a look at a plane blade's edge. The typical idea of the symetrical rounded tip after use is not correct. This is how a worn plane blade which didn't fail through bending or cracking looks like:







The wear on the bottom is from the steel rubbing over the wood. It forms a bulge which needs to be removed, otherwise this reduces the clearance angle too much and makes for a harsh ride. The wear at the top is from the shaving gliding over the steel. It is much longer, often very visible as a gleaming line on the face side of the blade (in a bevel down plane). This wear bevel doesn't need to be removed completely. It doesn't harm the working of the plane and it is allready fairly polished. So no need for a ruler trick in a bevel down plane.

So, to get practical, how do we know that we removed enough material from the bevel to get past the bulge on the bottom side of the blade? I think the best way to know that you removed enough is raising a burr along the full with of the blade. And then remove that burr in as clean a way as possible. 

I used to sharpen on waterstones and I can't feel any burr when using my 8000 grit waterstone. So I would grind on a 1000 stone at 25 degrees or so untill I got a burr. Then raise the blade about 5 degrees and remove that burr with the 8000 grit stone. In regards to steel removal that must have been the method that wastes the most. Completely removing the secondairy bevel on each honing! Nowadays I use oilstones and I can feel the burr from a translucent Arkansas. I can also feel how it is removed with carefull attention to both sides, flipping the blade up and down. A strop completes this action and removes the last tiny bits. No need to go back to the coarser stones all the time, so not waisting that "much" material.


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## woodbrains (26 Apr 2015)

Hello,

From Corneel's diagram, it can be seen why a back bevel would remove less metal to reach the point of true sharpness. Also, a burr will be raised at the junction of the upper surface and clearance surface (as referred to in the diagram) in other words, at the apex of the wear. This is not the point of sharpness however, and relying on the burr as an indicator as when to stop honing is a red herring. We have to work on the sharpening bevel for a fair bit longer after the burr is raised. Corneel's mitigates this somewhat by stropping, which is essentially producing a back bevel. I wonder whether reverting to oilstones for a burr raising indicator is not a backward step. A burr is felt because the sharpening medium is coarser, so the tool not as sharp, though obviously stropping fixes that. It is better to _see_ when an edge is sharp. I often feel a wire edge form, back it off on the stone and look for sharpness. If the wire edge is only just formed, I usually _see_ that the edge is not sharp. It is not difficult, in good light, to be able to see the wear bevel on the back has still remained, even if the burr was raised and removed. Of course I'm only talking minutiae here, and whether the difference is worth worrying about is down to the individual woodworker. But for the sake of this discussion, the wear bevel on the flat side must be removed for true sharpness and this is not the point the burr is raised.

Mike.


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## CStanford (26 Apr 2015)

Cheshirechappie":175s7kgo said:


> I think that post pretty well accords with what everybody else has said, though I'm not sure everybody excluded honing at 30 degrees from their computations.
> 
> There's one point I'd beg to differ on. From experience, I know it's perfectly possible to freehand hone and maintain a 30 degree secondary (working edge) bevel accurately enough for all woodworking purposes. Developing that skill takes a little practice, but once you've 'got it' it's ingrained for life. I fully accept that some people prefer to use a honing guide for any number of reasons, and that's fine - do whatever works for you - but to suggest that only a honing guide will keep the angle is bunkum - craftsmen have been 'keeping the angle' freehand for generations. Many still do.



Those who hone secondary bevels can simply drop down occasionally and hone on the grind to manage the size and angle growth of the secondary. There's no real overriding reason to develop an innate sense of 30* though this may be a result over time.

I've taken to grinding more often to keep the hollow lookin' good. Takes mere seconds.

On plane irons, I use Jacob's rounded under method which is the fastest and easiest to maintain of all.


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## lurker (26 Apr 2015)

G S Haydon":3qo99t6x said:


> This has to be a truly original sharpening debate, I don't recall one like it before!



Maybe, but it looks like a discussion about the bleedin' obvious to me


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## Corneel (26 Apr 2015)

woodbrains":3vf8w744 said:


> Hello,
> 
> From Corneel's diagram, it can be seen why a back bevel would remove less metal to reach the point of true sharpness. Also, a burr will be raised at the junction of the upper surface and clearance surface (as referred to in the diagram) in other words, at the apex of the wear. This is not the point of sharpness however, and relying on the burr as an indicator as when to stop honing is a red herring. We have to work on the sharpening bevel for a fair bit longer after the burr is raised.



But, what more do you want? The shavings have polished the surface, there are no nicks or scratches, and the non flat shape doesn't interfere with planing. Sounds pretty ideal to me.
(In a bevel DOWN plane! Bevel ups and chisels follow their own rules).



> I wonder whether reverting to oilstones for a burr raising indicator is not a backward step. A burr is felt because the sharpening medium is coarser, so the tool not as sharp, though obviously stropping fixes that.



An oilstone works very differently from a waterstone or sandpaper. The particle size is not very relevant to how an oilstone works. It mamages to creates large burrs because it somehow works "smoother". I think it pushes the steel around more then cutting it, which helps in burr formation. But you can get remarkably sharp edges from a worked in Arkansas stone, despite its rather coarse grit.



> It is better to _see_ when an edge is sharp. I often feel a wire edge form, back it off on the stone and look for sharpness. If the wire edge is only just formed, I usually _see_ that the edge is not sharp. It is not difficult, in good light, to be able to see the wear bevel on the back has still remained, even if the burr was raised and removed. Of course I'm only talking minutiae here, and whether the difference is worth worrying about is down to the individual woodworker. But for the sake of this discussion, the wear bevel on the flat side must be removed for true sharpness and this is not the point the burr is raised.
> 
> Mike.



I agree totally about this being minutiae.


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## Corneel (26 Apr 2015)

To give an idea about what we are looking at. I took my Record 05 from the drawer. It really needs to be sharpened again, but it made a good case for some microscopy. My microscope has 470 times magnification.

First picture is the face side of the edge. You can clearly see the wear, that is the whitish area just behind the edge. Somewhat lower down you can still see some scratches from the last polishing efforts.





For comparison an image from the bevel side. It is hard to get things in focus on a slanted surface like this, but I focussed on the edge a much as possible. The first black stripe is the wear bevel, the convex shape that limits the clearance angle. As you can see it is much shorter then the wear on the faceside. Lower down you see my last sharpening efforts. The whitish stripe just below the black one is the 8000 grit micro bevel. Lower down you see much coarser scratches probably from a 1000 stone (very out of focus).





As you can see, the wear bevel on the face side doesn't look any worse then the microbevel on the bevel side that was polished on a 8000 stone.


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## woodbrains (26 Apr 2015)

Corneel":2hm38jtw said:


> As you can see, the wear bevel on the face side doesn't look any worse then the microbevel on the bevel side that was polished on a 8000 stone.



Hello,

Do you not think so? It looks vastly superior to me. The scratch pattern in the back bevel is considerably finer than that of the wear bevel. Think of it another way, if the wear bevel was no different to a honed bevel, then our tools would never get dull!

In any case, I'm not concerned in how you sharpen, but in the interest of this topic, honing to a wire edge is not the point to stop, but until the wear bevel is removed. The OP contended that no matter how we sharpen, the same amount of metal must be removed to get to that point, and I think we must agree. However, a back bevel WILL save metal, as can be clearly extrapolated from your graphic representation on the worn blade. I'm not saying this is what we should do, but it is the only way I can think of where achieving true sharpness removes less metal.

Don't forget, I started a thread precisely about the action of oilstones consolidating metal and achieving finer results than expected, for particle size. I don't remember getting much support for the idea then, what has changed?

Mike.


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## Corneel (26 Apr 2015)

I must say, it is very hard to draw conclusions from these kinds of pictures. You really need a SEM to see it well. The wear on the face side looks very smooth to me in this picture, about the same surface roughness as the 8000 grit microbevel in the other picture. You certainly can't see scratches on this picture in that wear area on the face side. Another clue is when you look at it on macro scale. You see a gleaming line, which means that the shavings have polished the surface.

And the edge becoming dull has another source then the surface quality of the faces. It is because of the very tip of the edge which becomes rounded. Add to that the loss of clearance in a plane which is another important aspect of dulling.

Polishing the faces of the bevel isn't the most important part of sharpening other then making them smooth enough to avoid craters in the edge. But when they are allready smooth, you don't need to smooth them again. So that kind of negates the need of a backbevel for this.

BTW, I don't remember that thread about oilstones? But I think I agree with you in that respect.


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## Corneel (2 May 2015)

It looks like I am not alone with this opinion. While searching for something else, I happened upon this quote from Brent Beach' website. Brent Beach is the guy who did a lot of blade testing years ago and who made a lot of hoopla around backbevels, argumenting that you can't get a really sharp edge without a back bevel. But then he writes on a page about bevel up planes (http://www3.telus.net/BrentBeach/Sharpen/bevel up.html):



> Conventional sharpening techniques handle the conventional problem: the problem of sharpening a bevel down iron. Conventional sharpening techniques concentrate on the bevel side of the iron. Conventional sharpening techniques do a good job on the bevel side, do little on the back face, but this works out pretty well for bevel down planes. The back face of the iron gets the upper wear bevel, which is slightly rougher than a well honed bevel and is at a slightly greater angle than expected. The net effect of not working the back face of the blade is a slight increase in effort, with little decrease in surface quality except perhaps for soft and stringy woods (where the increased effective planing angle is a negative).



That does contradict with his opinions about backbevels a bit, doesn't it? Of course, when you are into sharpening with sub micron abrassives, you can get sharper edges when you hone away the wear on the back of the blade completely. But it is hard to find much difference in actual work when you sharpen a bit less fastidious.


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## CStanford (2 May 2015)

You may have missed an earlier thread where it was pointed out that Brent Beach has a whopping $50 invested in the microscope he uses to draw all of his profuse conclusions. You should read the part of his website where he discusses the blue plastic body of his microscope casting a shade of color on his specimens, and other general lighting difficulties, to decide whether you feel his observations are anywhere near reliable.

After you read about Brent's microscope then please read about a real metallurgical microscope:

http://www.metallurgicalmicroscopes.com/


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## Corneel (2 May 2015)

My microscope was relatively expensive for an USB model, but it is still very difficult to draw any conclusions from the pictures.


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## CStanford (2 May 2015)

Corneel":g2qbqu4p said:


> My microscope was relatively expensive for an USB model, but it is still very difficult to draw any conclusions from the pictures.



True, and professional training in metallurgy, materials science, etc. wouldn't hurt either. I'm sure Brent is a nice guy and his intentions are good but at some point people need to realize he is no expert nor has he equipped himself in any meaningful way, falling way short of even being barely adequate. The images he's captured are not reliable nor, likely, are his interpretations of them. One always allows for the blind squirrel to find a nut every now and then and we applaud him when he does. But, we aren't going to follow him around in our search for them, are we?


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## woodbrains (2 May 2015)

Hello,

Who mentioned Brent Beach, so they can slag him off, from a point of equal ignorance, BTW? Not fair and unnecessarily argumentative. Besides, we do not have to be watchmakers to be able to tell the time.

It is clear that the point at which a wire edge is raised occurs _before_ the wear on the back of the tool is removed. The diagram Corneel provided us shows us this. If this is the point you want to stop, then fine, but it is not the point at which the tool is at its sharpest. Even if the wear bevel on the back is as polished as the hone would produce, it is not at the correct angle, it is dubbed over. I can see this with normal, unaided eyesight, after the wire edge has been raised and removed. The wire edge is an indication that sharpness is approaching, but usually more strokes on the stone are required to get there and remove the wear totally. (Or a ruler trick back bevel) In my opinion, this make the wire edge as an indicator not too useful since we have to recognise by sight when the edge is sharp. (There is no light reflection on a truly sharp edge) If removing the wear is quicker with water stones, then the fact that they may not raise a burr is no disadvantage because I look for sharpness, not feel for it. Besides, our eyes can detect surface deviations 10 times smaller than our fingers can feel. Stropping effectively adds a back bevel, which is as good a way of doing it as any, but why an extra step to an already longer process to preserve the effect of a wire edge, which has no real use, when thought about logically. I used oilstones for decades, and they work fine, but unquestionably take longer to get to similar levels of finish. 

Mike.


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## CStanford (2 May 2015)

The advantage of using fast media like waterstones and sandpaper is that the process simply gets done and done fast. Why the navel-gazing? This is the chief advantage of these products - one can start at a finer grit and still process a dull edge very rapidly. Call it what you want, we're just removing bluntness. I suppose it would be lovely not to waste an angstrom of steel but obviously a fool's errand in the end. Look, feel, do what you need to do but just remove the steel necessary. 

Because of their ability to remove material rapidly, if anything, fast media totally obviate the need for back beveling and all that hoo-hah.

Think about it like this -- if you owned a big kick-a$$ 20"++ wide 3 phase umpteen horsepower planer then a scrub plane wouldn't even rise to the level of quaintness. You don't need it. So goes the back bevel to the extent it's being recommended to remove bluntness. For Pete's sake put the petunias and Shakespeare's sonnets aside and just blow past 'the wear' with the fast media you already own. Oilstone users can just drop back to a medium stone if the edge has really gone off. No big deal, just remove more steel. Let your eye, your thumbnail, sense of timing and experience, hair on your arm, whatever, be your guide.

We're removing what has to be removed. All this other stuff is like becoming fascinated and infatuated with the off-cut from a workpiece instead of the workpiece itself. You removed wood because it was not needed. You're doing the same thing with blunt steel. It's like planing a board to width and all of a sudden becoming perplexed about how to take off the last 64th of an inch and thinking you need to conjure up some new scheme to remove it. Keep on planing. Keep on honing. Until you get where you need to be. I can't possibly imagine anything simpler or more basic.

And yes, if you really push an edge you'll have to remove more steel to make it sharp again and it this might require and additional measure of patience. I'm going to stand by my mailbox awaiting a nomination for the Nobel Prize in physics.


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## bridger (2 May 2015)

Corneel":1zqbassu said:


> My microscope was relatively expensive for an USB model, but it is still very difficult to draw any conclusions from the pictures.




I also have a cheap usb microscope. While I am not declaring that it makes me an expert at anything, and certainly not a metallurgist, it has helped me quite a bit. I'd say it did bump my sharpening up a grade to look at my edges at that magnification.

For instance, this straight razor looks terrible, but shaved pretty well as pictured:


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## CStanford (2 May 2015)

Under magnification a lot of edges look like they couldn't cut overcooked pasta.


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## bridger (2 May 2015)

CStanford":31hm1t7j said:


> Under magnification a lot of edges look like they couldn't cut overcooked pasta.




I'd even go so far as to say that for some kinds of cutting a slightly ragged edge performs better than a polished one. thus a kitchen knife which gets the sharpening steel applied regularly will do the job of cutting foodstuffs well but wouldn't last a moment cutting wood. most things a kitchen knife cuts could be described as squishy bundles of wet fibers saturated with sugars and fats. try planing that!


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## Racers (2 May 2015)

I have a cheese plane..







 

Pete


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## CStanford (2 May 2015)

bridger":1tpden0x said:


> Corneel":1tpden0x said:
> 
> 
> > My microscope was relatively expensive for an USB model, but it is still very difficult to draw any conclusions from the pictures.
> ...



That edge looks fine to me. I'm not surprised at all you got a good shave from it.

The common housefly looks beastly under magnification. Don't lose perspective, as so many seem prone to do.


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## Corneel (3 May 2015)

CStanford":fnd7guui said:


> The advantage of using fast media like waterstones and sandpaper is that the process simply gets done and done fast. Why the navel-gazing? This is the chief advantage of these products - one can start at a finer grit and still process a dull edge very rapidly. Call it what you want, we're just removing bluntness. I suppose it would be lovely not to waste an angstrom of steel but obviously a fool's errand in the end. Look, feel, do what you need to do but just remove the steel necessary.
> 
> Because of their ability to remove material rapidly, if anything, fast media totally obviate the need for back beveling and all that hoo-hah.
> 
> ...



Well, navel gazing is what these forums are all about isn't it :mrgreen: 

I completely agree with your post above. The discussion in the last two pages was about what needs to be removed exactly. The wear on the face side of a bevel up plane can be quite long and my point was that it doesn't need to be removed all the time. When you have raised a good burr on a 1000 waterstone or an India stone, then you are beyond the rounding of the very edge, but not neccessarily beyond all the wear on the face side. In my opinion that is good enough. And mr. Breach seems to hold the same opinion.


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## CStanford (3 May 2015)

Remove enough steel to leave no doubt. The alternative is pointless.


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## bridger (3 May 2015)

Racers":20c1fxli said:


> I have a cheese plane..
> 
> 
> 
> ...




Touche.....


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## CStanford (4 May 2015)

Oh dear surely you wouldn't dare use that cheese plane without fettling it. The angle looks stock from the factory and clearly the face isn't nearly flat and polished enough to take half-thou shavings from sharp cheddar.

I'm looking at property in Vermont to set up making these as a boutique endeavor. Initial pricing studies indicate these will run about $250 US. Thoughts?


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## JimB (4 May 2015)

CStanford":28alopo3 said:


> Oh dear surely you wouldn't dare use that cheese plane without fettling it. The angle looks stock from the factory and clearly the face isn't nearly flat and polished enough to take half-thou shavings from sharp cheddar.
> 
> I'm looking at property in Vermont to set up making these as a boutique endeavor. Initial pricing studies indicate these will run about $250 US. Thoughts?


Surely someone is working as we speak to make a suitably 'grained' cheese to get the best out such a tool.


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## CStanford (5 May 2015)

Probably the Japanese to be used at a cheese planing competition.


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## Jacob (6 May 2015)

The usual hilarious degree over over-thinking going on in this thread!
If you free-hand hone just enough to get a burr right across the full width of the blade (it's easy to miss a bit in the middle where there tends to be most wear) you are removing the least amount of metal for a sharp edge. 
If you also dip and generate a slightly rounded bevel you defer the need for grinding. 
If a bevel doesn't come up quickly a bit of a face bevel speeds this up - most people do this sub-conciously anyway every time they "flatten" the face - by putting more pressure towards the edge and even by lifting the blade a touch (the ruler trick without a ruler). The alternative; to attempt to literally flatten the whole face every time you sharpen, would be madness.
For many people - over-zealous grinding, especially hollow on a small 6" wheel, probably wastes most metal and most risks over-heating. Flat is better (belt sander etc) - or a large diameter wet wheel.
Keep it simple! A little and often.

It works for me - I've been doing a lot of hand planing recently and would simply not have time for fashionable but lengthier sharpening processes - least of all with fashionable thick blades. Exception here - I have been using a 26" woody with a trad thick blade - but just for straightening the arris on long timbers, which gives a reference for flattening the edge (after having flattened the face). A no. 8 would be better but I haven't got one.


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## bridger (6 May 2015)

I do give the flat side a wipe or two at least on a fine stone each time I sharpen, and I do concentrate on near the edge. i don't do the ruler trick or otherwise deliberately lift the handle or back bevel. Yes it does eventually result in a belly, which is no problem for most kinds of chisel work, and even a bit of a help for some. When it gets too much I'll go ahead and work it back to flat. There are a few chisels that do demand an accurate flat back, and they get different care.

For found vintage chisels with deep bellies or pitting that must be removed I have found a process to quickly return them to shape involving an angle head die grinder with a small abrasive disk, an extra coarse and a 600 grit dmt plate and a 1000 grit king red brick.


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## Jacob (6 May 2015)

bridger":3gisjexa said:


> ..... There are a few chisels that do demand an accurate flat back,


Er - when, where, why, what?
Carvers use and depend chisels much more than woodworkers like most of us. They don't seem the slightest bit bothered about bevels on both sides, flatness etc - and confine polishing just to the bevel itself.


> For found vintage chisels with deep bellies or pitting that must be removed I have found a process to quickly return them to shape involving an angle head die grinder with a small abrasive disk, an extra coarse and a 600 grit dmt plate and a 1000 grit king red brick.


I'd just leave them alone and use them "as is" or use another one. They are dirt cheap why oeuf about? All this flattening and polishing is a complete waste of time.
All old plane blades and chisels I see seem to be slightly convex in the length due to the face flattening we're talking about - but nothing ever which could deserve the term "bellied" .


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## Phil Pascoe (6 May 2015)

Why did you feel the need to show us your photo?


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## MIGNAL (6 May 2015)

That's wasted food not wasted steel.


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## Jacob (6 May 2015)

It's useful as a bench hold-down.


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## Phil Pascoe (6 May 2015)

While we're on cheese planes - my friend's wife, a very well educated lady, believed for several years that a small, curved Surform plane was a purpose made Parmesan grater.


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## bugbear (6 May 2015)

phil.p":1m7ggfrx said:


> While we're on cheese planes - my friend's wife, a very well educated lady, believed for several years that a small, curved Surform plane was a purpose made Parmesan grater.



You know about Microplane, right?

BugBear


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## bridger (6 May 2015)

Jacob":33dn0gma said:


> bridger":33dn0gma said:
> 
> 
> > ..... There are a few chisels that do demand an accurate flat back,
> ...



I have a short wide cranked handle chisel that I use for close paring flush with a finished or near finished surface that I keep the flat side of... err.... flat. It turns out to be surprisingly useful thus. Also, a few otherwise unremarkable bench chisels, kept flat with similar results.


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