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how to sharpen a serrated knife blade in 90 seconds

 
paul wheaton
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Ray, "the edgemaster" demonstrates how to sharpen a serrated knife blade.   The tip was sharpened the way you would sharpen a normal knife blade and then he used almost exclusively the power rag buffer wheel.   

He said something about getting a wire edge or a feather edge that I didn't understand.  Nor did I understand what he was doing by running the knife on the wood every ten or fifteen seconds.

When i handed him the knife, I knew that blade was very dull.  I had stopped using it months previously because it was useless and I could sharpen the other blades.  I was thinking that I would need to learn how to sharpen the serrated edge first.  I'm glad I bumped into "the edgemaster" - because what he handed back to me was crazy sharp.  Razor sharp.   He says he polishes the blade to what it is supposed to be.

This is my leatherman wave tool. 

I filmed Ray in Missoula, Montana.


 
paul wheaton
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I would like to know:

1)  what does "wire edge" mean?

2)  what is he doing running the blade on the wood every ten seconds?

 
                        
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Location: South Arkansas
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If I understood him right the "wire" or feather edge is the small metal strip that forms on the edge of the blade when sharpening it when he rubs the blade on the board it is testing the sharpness and removing the "wire" edge to receve a sharper edge i rember this from watching the woodwright shop on pbs when i was younger
 
                    
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Yes, the wire edge is like a small burr, a slight rolled bit that forms at the edge. It has to be removed to be sharp.

 
                    
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I should maybe point out that while on a knife a wire edge is not desirable, on a scraping tool it is the wire edge that provides superior scraping action.
 
T. Pierce
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Location: Virginia
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i couldnt understand half what the fella said.  but that wire edge is just a rolled edge that comes from sharpening one side of the blade.  it has to be removed to get the other side sharp,,,,and in turn both sides of the blade will be worked the same. to get a good final edge.  ive watched an old friend of mine that is a excelllent at sharpening knives using just a stone.  he uses some old leather mule traces to really get a fine edge on a blade.  the leather also helps remove that rolled edge.  work it some more on the stone.  finish it up with a few strops on that thick leather and you get a mighty keen edge.
 
Charles Kelm
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Location: Western Washington (Zone 7B - temperate maritime)
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I would like to try this.  Do you think I can just take one of the standard grinding wheels off the two wheeled grinder I have, and replace it with a rag wheel?  I think they sell rag wheels (or whatever they call them) at Harbor Freight pretty cheap, along with the buffing compound.  We just got a new Harbor Freight in Bellingham, so that's a bonus (like you guys care, right?)
 
Dave Bennett
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Charles Kelm wrote:
I would like to try this.  Do you think I can just take one of the standard grinding wheels off the two wheeled grinder I have, and replace it with a rag wheel?   I think they sell rag wheels (or whatever they call them) at Harbor Freight pretty cheap, along with the buffing compound.  We just got a new Harbor Freight in Bellingham, so that's a bonus (like you guys care, right?)


In a word...........Yes.  Get some fine "jewelers rouge" and make sure that your "rag wheel" is spiral sewn cotton.  I usually only use three different "grits" and if you are doing a serrated edge you just want a polishing rouge which is normally grit free and is actually only polishing.  I do not use black rouge on my cotton buffing wheels because it will get embedded in the wheel and not allow a mirror finish.  If the blade of any knife has been neglected for a long time use a sisal wheel with black rouge.  For the highest polish use a loose cotton wheel but not for putting an edge on a serrated knife.  For that you want to use a spiral sewn cotton wheel and white rouge which is also great for removing scratches on harder materials like the steel in a knife blade.  Blue rouge and the reddish rouge are about the same and are excellent for the final polish.  Be patient and work carefully with a "light hand."
Peace.
PS: I just looked at the harbor freight site and they have a 6" spiral sewn cotton wheel and a buffing compound set that has white a red rouge.  You will use the red rouge for sharpening and the white for the final polishing.  Buy several of the cotton wheels you will discover that you have lots of "stuff" to make really shiny. LOL
 
Charles Kelm
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Location: Western Washington (Zone 7B - temperate maritime)
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I bought brown here: http://www.harborfreight.com/power-tools/power-tool-accessories/1-4-quarter-lb-brown-polish-compound-96775.html but I can return it if you think it is the wrong choice for doing what the guy did in the video.  They had white, black, other colors too.  Got the spiral sewn rag wheel.  Thanks.
 
Dave Bennett
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Charles Kelm wrote:
I bought brown here: http://www.harborfreight.com/power-tools/power-tool-accessories/1-4-quarter-lb-brown-polish-compound-96775.html but I can return it if you think it is the wrong choice for doing what the guy did in the video.  They had white, black, other colors too.  Got the spiral sewn rag wheel.  Thanks.

The white stuff is really for soft metals but as a polishing medium for steel it makes a mirror finish.
 
Charles Kelm
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Location: Western Washington (Zone 7B - temperate maritime)
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Is that what you would use to do what the guy did in the video above?  White?
 
Dave Bennett
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Charles Kelm wrote:
Is that what you would use to do what the guy did in the video above?  White?

If the knife was still somewhat sharp yes.  If it was in bad shape I would use the reddish rouge which is sometimes called brown.  Brown is also called Tripoli rouge and is good for soft metals or a very high polish.  White works similarly to white.  I used make sterling silver "stuff" back in the days of "hippies" I just never got over being one LOL.  I will die a hippie.
 
Charles Kelm
Posts: 170
Location: Western Washington (Zone 7B - temperate maritime)
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Well then I guess after you got done using the brown on a rough blade, you would finish the blade off with the white stuff, right?  Different rag wheel for the white stuff, or same wheel?  How do you know when you have the right amount of buffing compound on a brand new wheel?
 
Dave Bennett
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I use a different wheel for different grit rouges.  The same spiral sewn cotton though.  On a new wheel turn on your grinder and when it is up to speed lightly press the rouge against the wheel.  It will heat up rapidly and soften.  You don't need much.  Using the white stuff on steel you will discover that it doesn't matter if there is too much rouge.  The way to tell if you applied too much is if the rouge is spitting all over the place and melted rouge shows on the blade.  Use less the next time.
Experience is the best way to learn to polish metals.  I have been doing it since I was a youngster.  I like hand polishing wood too.  I guess I just like making really smooth surfaces.
 
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