How to hone concave part of warped blade?

jeffus

Active Member
I've talked to a few honers who claim to be able to hone warped blades in their sleep, but I just don't get it. The convex side is easy with the rolling X, but how do you get the concave side? Do you use a very skinny hone with rounded edges?

cheers,
jeff
 

Smythe

Well-Known Member
You are correct; a rolling “x” stroke will not properly sharpen a blade. In fact it will only sharpen one side of the bevel. A straight up and down stroke will not work either.

A warped razor will only roll on one side (so you can touch all of the edge on that side). However when the blade is flipped, the middle of the edge will not touch the hone… only the point and the heel.
In fact, a great way to tell if a blade is warped... compare the spine wear and bevels on both sides, if they are uneven, chances are the blade is warped and may be difficult to hone for the inexperienced.

There are two ways to sharpen the blade
1) A narrow hone 30-40mm or A about 1 ½ inch wide is perfect for most warped blades, and works just fine for un-warped ones too… of course the edges of all hones should be rounded, but I recommend only slightly more rounded than normal for the warped blade (more rounding is not a problem for un-warped blades).
However some find it difficult to keep the blade flat on a narrow surface… but in my humble opinion this can be solved with practice… indeed most of those (expensive) vintage German Water hones (the ones in the hinged box) are very narrow, and folks in the old days used them quiet successfully to sharpen razors.

The other way is difficult to explain but rather easy to do in practice.

With the availability of wide hones “today”, we tend to use the middle of the hone most of the times. However when dealing with a warped blade it is best to work close to the edge of the hone… as the blade falls off the hone during the final part of the “X” stroke, the edge of the hone will have a chance to touch the middle of the blade that normally does not touch on that side of the blade (the concave side).
So you may roll one side of the blade (convex side), but the other side you bring down the tang and allow the edge of the hone to "follow" along the edge of the blade... (or to put it another way... Allow the edge of the blade to "ride" the edge of the hone).

(*Caution* you are not actually using the very edge of the hone... you are using the surface of the hone close to the edge of the hone to contact the middle part of the blade as you bring the tang down... it is a practiced movement, to contact the hone but not bring the tang so far down that you are actually honing on the edge of the hone... as a guide, watch the "black" on the surface of the hone to see how close to edge of the hone you are contacting).

If you perfect this method, not only will you be proud of the resulting edge, but you may never get those unsightly “uneven” bevels or spine were when you are done (that is: if they weren't there, or were very small to begin with, or you removed the hone were during the restore).

Bart made a Wiki entry in SRP explaining this some time ago but I cannot find it at the moment, but I will post a link when I find it (incidentally I do not see it in the Sharpening Academy).

Hope this helps my friend.


EDIT: found it:
Please, Log in or Register to view URLs content!
 

Smythe

Well-Known Member
Notes:
As you gain experience honing a warped blade, you will become familiar with which side of the blade is warped concave and which side is the convex. The two sides will have a different sound as it passes over the surface of the hone. They will also have a different “feel”. As you roll the stroke on the convex side it will roll easy with a smooth sliding sound while the concave side will not roll and has a “scraping” sound.

The convex side must be rolled because the hone is flat but the convex side is curved so you need to roll the curve in order to sharpen that side… rather easy once you understand the rolling stroke (of course as we already discussed the other side won’t roll).

As a consequence of this “warp”, sharpening the blade may require more strokes to remove the same amount of steel as a un-warped blade during the same stroke because while an un-warped blade contacts the entire edge during the stroke (the blade is flat and the hone is flat), the warped blade only has a small part of the edge contacting the hone at any time during the stroke. Consider this the same when sharpening a smiling blade (only part of the edge contacts the hone at a time during the stroke).

Stropping a warped blade is no different from stropping an un-warped blade (the strop will conform to the shape of the blade (as with ANY blade it should be properly sharpened before stropping), however you would use the same stroke(s) to touch-up as you did to hone it.
 

Paul

Well-Known Member
I like a narrow hone for warped blades, and I'm finding that I like them for straight ones too. However, I've used the technique that Smythe outlined with great success with my 3" Shaptons as well. :thumbup:

Excellent post, Sir!
 

tat2Ralfy

Well-Known Member
Spot on post Sir Smythe :thumbup:
Thats just how I do it, I angle the toe end up slightly and concentrate the blade on a strip about 1/2" wide down one side of the hone, just a couple things to watch.
1, make sure you dont work the edge on too narrow a strip because you might
A, catch the edge even if its chamfered and
B, end up dulling the edge, a very small contact area on the hone (as you would have if you used a rounded stone) will not give the keenness we need.

If you ever had too, (and I have) you can lap the side of your hone, providing its a combo!) and use that to hone up those problem blades ;)
 

jeffus

Active Member
Smythe said:
So you may roll one side of the blade (convex side), but the other side you bring down the tang and allow the edge of the hone to "follow" along the edge of the blade... (or to put it another way... Allow the edge of the blade to "ride" the edge of the hone).
Thank you, that does indeed help. One further clarification please:

I understand your description for bringing the tang down to get the toe end of the concave side, but what about the heel end of the concave side? Do you start with the toe hanging over the other side of the hone?

cheers,
jeff
 

Bart

Well-Known Member
Cedrick,

you saved me from a lot of typing.:)
Excellent write-up.:thumbup:
Smythe said:
Bart made a Wiki entry in SRP explaining this some time ago but I cannot find it at the moment, but I will post a link when I find it (incidentally I do not see it in the Sharpening Academy).
Please, Log in or Register to view URLs content!
It's not good enough for the Sharpening Academy. I've been planning to rework that article for a while now. Time is a big issue.

If I'm allowed one addition to what's already been said in this thread:

They were not stupid in the old days. Putting a smiling curve onto an edge, solves all problems with the concave side of a warped blade. (which is a pretty common occurrence). Smiling blades need a rolling stroke or a small hone, no matter what, so no one ever notices a warp when present.
A smile projects the middle part of an edge enough to make it still touch the hone, regardless of a little concaveness.

Best regards,
Bart.
 

Smythe

Well-Known Member
Damn!!!... Bart, you solved that with one paragraph. Simply bread-knife a smile on the edge, then do the rolling stroke as normal.:)
 

jeffus

Active Member
Bart said:
If I'm allowed one addition to what's already been said in this thread:
With additions like that, you can add as much as you possibly can to this topic. I had never tied together smiles and warps. A light bulb goes off.

thanks,
jeff
 

Matt

Well-Known Member
Now... If there WAS this little thing
... I wouldn't have to post it - Really great tip, Bart, thanks a heap!

I'll have to watch my back carefully from now on... hahah :lol:

kind regards,
Matt
 

tat2Ralfy

Well-Known Member
matis said:
Now... If there WAS this little thing
... I wouldn't have to post it - Really great tip, Bart, thanks a heap!

I'll have to watch my back carefully from now on... hahah :lol:

kind regards,
Matt
Oh Shit! Now you done it hahaha Its a good job they wont let me out the country or it would be operation polish keyboard enema after that post!! hahaha
 

Smythe

Well-Known Member
matis said:
Now... If there WAS this little thing
... I wouldn't have to post it - Really great tip, Bart, thanks a heap!

I'll have to watch my back carefully from now on... hahah :lol:

kind regards,
Matt
Dude!! you better run!... run!!... RUN!!!! before the barkeep sees that Th***s button.
 

maro

Well-Known Member
You could also delete your post, Matis, but now it's too late. It's been quoted so many times...
 

Bart

Well-Known Member
Well, you asked for it...:sneaky:

Our special Thanks Exterminator Team is on the way.:thumbdown:

 

tat2Ralfy

Well-Known Member
Bart said:
Well, you asked for it...:sneaky:

Our special Thanks Exterminator Team is on the way.:thumbdown:

Although the pic dont show on my Google chrome browser I see from quoting the post it most likely contains some fuckwit buried arse up in sand...lol

I look forward to the Airdrop Sir Bart, Special Operations Sargent Ralfson suited booted and ready!!

 

Matt

Well-Known Member
maro said:
You could also delete your post, Matis, but now it's too late. It's been quoted so many times...
Sure I could, yet one should fearlessly face his destiny! :mad: [note="Hagakure"]The Way of the Samurai is found in death. Meditation on inevitable death should be performed daily. Every day, when one's body and mind are at peace, one should meditate upon being ripped apart by arrows, rifles, spears, and swords, being carried away by surging waves, being thrown into the midst of a great fire, being struck by lightning, being shaken to death by a great earthquake, falling from thousand-foot cliffs, dying of disease or committing seppuku at the death of one's master. And every day, without fail, one should consider himself as dead. This is the substance of the Way of the Samurai.[/note]Or meditate upon having one's ass severed by a keyboard! :lol: :lol: :lol:
Should I fail and be defeated, let my humble collection of 10 razors be distributed among top ten forum contributors, excluding the executioner! :lol:

kind regards,
Matt
 

tat2Ralfy

Well-Known Member
matis said:
tat2Ralfy said:
Oh Goody! :thumbup:
Bastard... :cry:
:lol: :lol:
Hahahaha I did mean "Oh Goody" to any lucky inheritors of a part of your beautiful collection, obviously I could never ever be associated with any acts of covert skulduggery :|
 
Top