Flattening the back
#21
Just spent a wee bit of time, working over 4 chisels...
Winkgrin 
   
Including a handle  repair and a handle replacement...
Free hand sharpened.  The wide Union Hardware chisel needed a new handle made...
Cool 
   
Whatever works best.....

That skinny chisel is a Buck Brothers, says so right on the blade.   yellow handle is a Stanley No. 60.   Just going through some extras, to see what will go into the new Tool Chest project....

BTW: I do NOT use the "Ruler Trick"  at all.....planes or otherwise...
Show me a picture, I'll build a project from that
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#22
(03-17-2020, 08:59 PM)wmickley Wrote: Grains won't realign depending on what direction you hone.  (I'm a metallurgical engineer - trust me.)  Sharpening is basically removing material by abrasion.  The grains don't go anywhere.  The only way you can realign grains is to deform it by whacking it with something hard, or heat treat it.  Sideways sharpening will indeed leave micro-scratches across the edge.  Interestingly enough, this is how Harrelson Stanley was taught in Japan to hone an edge - sideways.  He even invented a honing guide that facilitates sideways honing.  Just before he finished, he would hold the edge dead on perpendicular to the finest grit waterstone, and with only the weight of the blade, slide it sideways across the stone.  He claimed that removed the portion of the edge that would otherwise break off during use due to those sideways scratches.  He called it jointing.  He then would do a couple of very light strokes more of honing and declare it done.

I met Ron Hock in 2011 just before his book was published. I didn't know if I should buy the book so I asked him a question to see how much he knew. I don't want to tell the question, but here is his answer:

"Absolutely not! The only way ...... now wait a minute....... I better ask someone about that."

I met Harrelson Stanley two years later. As I looked at his side sharpening jig he told me I would never be able to to learn to sharpen without his jig, that freehand sharpening did not work. I was trained to freehand sharpen before little Harry was born.

Sharpening is very much more complicated than you suggest. (Trust me, I am a woodworker.)
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Sideways sharpening will indeed leave micro-scratches across the edge. Interestingly enough, this is how Harrelson Stanley was taught in Japan to hone an edge - sideways. He even invented a honing guide that facilitates sideways honing.

Karl Holtey sharpens blades this way also...and he marketed them..I had one years ago, purchased from Woodcraft..Holtey has plane making and sharpening pretty well down pat...
Big Grin
Often Tested.    Always Faithful.      Brothers Forever

Jack Edgar, Sgt. U.S. Marines, Korea, America's Forgotten War
Get off my lawn !
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#23
There is some realignment of structure below the gored (abraided) surface of the metal when sharpening. My memory says about equal to or twice the depth of surface scoring; shown in electron photographs of cross-sectioned edges. Diamonds cause deeper movement. Think plowing and tilling a planting surface. The next session will remove the previously disturbed material. 

All this tells me to sharpen somewhat parallel to the blade's travel. I would do that anyway to avoid convoluted wear on the abrading stone.

Japanese designs don't subscribe to western methods. You don't want to play the ruler trick on hollowed japanese steel. It screws up the wear around the hollows. 

Everyone here will disagree with me, but I am finding two flat surfaces forming a wedge on a cutting tool easier to manage and control. They're even finer edged. I can dull an edge on an 8k stone too easily by farting around with stupid secondary angles. 

But, freehand curves look pretty so your multi-bevel angles are your choice.
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#24
Just to clarify, deformation caused by sharpening isn't what I would consider to be "grain realignment." When you sharpen and a burr forms, that's bending or plastic deformation of the very thin edge. Nothing is happening to the grains behind that deformation. If sharpening only caused "grain realignment" there would be no such thing as swarf. Swarf is the metal removed by abrasion. I don't sharpen using the Harrelson Stanley method, but I did try it on one of my more expensive Japanese paring chisels. It worked, and honestly, I can't tell the difference in sharpness between sideways sharpening and more conventional sharpening. At some point, it doesn't really matter which direction the scratches go. Either method will leave you with a plenty sharp edge and 99.99% of cutting using your tools will damage that edge to the point where you will need to rehone it.
Still Learning,

Allan Hill
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#25
Ahill is correct, grains don't go anywhere.  The only way you can realign grains is to deform it by whacking it with something hard,  an example would be forging or heat treat it. Abrading metal off with what ever medimun you chose, whether it be by grinding, stoning, or lapping is only removing metal and leaving scratches. It is just like sanding wood. When you sand wood you only decrease the depth of the scratches by going with finer sandpaper the wood has not changed.

To me putting the scratch marks parallel with a cutting edge would be like sanding cross grain on a piece of wood. Hypothetically a parrell scratch mark at the cutting edge could cause the whole edge to roll

Tom  
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#26
(03-22-2020, 10:26 AM)tablesawtom Wrote: Ahill is correct, grains don't go anywhere.  The only way you can realign grains is to deform it by whacking it with something hard,  an example would be forging or heat treat it. Abrading metal off with what ever medimun you chose, whether it be by grinding, stoning, or lapping is only removing metal and leaving scratches. It is just like sanding wood. When you sand wood you only decrease the depth of the scratches by going with finer sandpaper the wood has not changed.

To me putting the scratch marks parallel with a cutting edge would be like sanding cross grain on a piece of wood. Hypothetically a parrell scratch mark at the cutting edge could cause the whole edge to roll

Tom  
.........................
Hypothetically a parrell scratch mark at the cutting edge could cause the whole edge to roll....

OR it "may" strengthen the edge by forming a single "wall" { for lack of a better word } instead of a series of small "teeth".....I think this is the theory Karl Holtey used on his blades. A "toothed edge" is not as strong as a "smooth" polished edge...An edge with "teeth" is preferred for some "softer" materials but not the harder ones...
Often Tested.    Always Faithful.      Brothers Forever

Jack Edgar, Sgt. U.S. Marines, Korea, America's Forgotten War
Get off my lawn !
Upset





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#27
When you sharpen and a burr forms, that's bending or plastic deformation of the very thin edge. Nothing is happening to the grains behind that deformation. Again Ahill is correct. An example is when you bend steel, metal flows toward the bend on the inside of the neutral plane but away from the bend  on the outside.

I haven't heard of plastic deformation since I stopped teaching die making at the local community collage. Way to go Ahill.

Tom 
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#28
If anyone is interested in learning about sharpening and what occurs to the abraded metal check the following link that is specifically related to my remark that has nothing to do with the expostulations following it--I know what to do with a burr. If you want to discover more keep going.... There are 33 articles just as informative.

https://scienceofsharp.com/page/2/
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#29
(03-22-2020, 10:46 AM)Timberwolf Wrote: .........................
Hypothetically a parrell scratch mark at the cutting edge could cause the whole edge to roll....

OR it "may" strengthen the edge by forming a single "wall" { for lack of a better word } instead of a series of small "teeth".....I think this is the theory Karl Holtey used on his blades. A "toothed edge" is not as strong as a "smooth" polished edge...An edge with "teeth" is preferred for some "softer" materials but not the harder ones...

But a butcher steels his edge because it rolls and it needs to be straightened so that it will cut. A steel does not sharpen just straightens. So using Karl's theory after a person takes a few strokes with his plane  it will have to taken it apart and sharpened, but not straightened because of roll, and the time frame would depend as you say on the hardness of the material being cut verses blade rockwell 'C".

The perfect cutting angle is 22 .5 degrees. But perfect cutting angle and a usable cutting angle are two different things. A paring knife is usually sharpened at a 25 degree included angle. And a plane blade sharpen at a 25 degree angle, it is the same angle as the knife. If you divide the plane angle in half and times the two you get an included angle of 25 degrees  just like the knife. In othewards you get the  same angle. 30 degree angle covered in next paragraph

I do not know what a butcher knife is sharpened at but Tormek instructions say 25 degrees for a paring knife and 40 degrees a hunting knife. The 40 degrees is because the edge need to be stronger, but to be stronger sharpness is sacrificed because the perfect angle is 22.5 and you can't have both. The same holds true  with chisels  and plane blades, the recommended angle for hardwood is 30 degrees, the edge is stronger and holds up better in hardwood but is not as sharp just stronger. 

Toothing blades compared to straight blades is like comparing apples and oranges, different application much like a paring knife versus a hunting knife, both are knives, just the application is different..

So if meat (which is softer than wood ) will roll a cutting edge  and the butcher has to steel the knife to keep the edge straight, what do you think hard wood verses soft wood will do to a cutting edge. When your plane blades starts to stop cutting usually it is removed and the edge is touched up on a stone and then the a couple of passes on the flat side and you are back in business. Note no real reshaping or hard cutting of the edge, just a touch up and you just did the same thing a butched did with his steel ( Rolled Edge Straightened) Toothed verses straight is application and angle is edge retaining ability. 

ON a personal note: whether the micro scratches go parallel to the edge or perpendicular to the edge is really a moot point. For me it is easier for me to screw up an edge sharpening it with the scratch line going parallel to the cutting edge so I have them perpendicular.  

And again grain doesn't change just as Ahill stated, plastic flow happens.

Tom
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#30
On a personal note: If my edge seems to me as getting dull I just stop and resharpen, and get on with what I was doing. A Project only gets closer to completion when work is being done and if sharpening no actual work is being  done on a project. And if the time is being spent sharpening or worrying about the molecular structure of steel, no work is getting done.  in my trade it is called Time in the chip.

Speaking Off getting work done, the best way to get a lot of nice tools is to build for the wife and get projects done and out of the shop. Trust me, the wife will find you the money to buy what ever you want or say you need for the shop you won't have to. My wife take real pride in what I make and she doesn't hesitate to show off what she has and that I made it for her. Now I have been woodworking for about 46 years and the other day she asked me what she could buy for me and I said I had pretty much everything I needed. She just chuckled , said that will be the day and walked away still chuckling to herself.

Normally I wouldn't respond to posts like this, it is just that there is a pandemic out side and  at my age I am trying to stay out of harms way.

Tom
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