how to sharpen a serrated knife blade in 90 seconds

[paul wheaton]

Wow, that's fast.

And I had no idea that sharpening a blade could be that fast!

When I saw he was gonna just use the rag wheel buffer, I thought it was gonna be lame, but the knife went from useless to razor sharp!

I have two questions:

1)  what is he talking about when he says "wire edge"?

2)  what does he keep doing by running the blade on the wood every ten seconds or so?

http://www.youtube.com/paulwheaton12#p/u/0/SOFcnP79bBU

Please forward to folks that might be interested in this sort of thing.

Many thanks!

[MountainDon]

Wire edge is a slight curl of metal that happens when sharpening. You have to get rid of it to have a sharp cutting edge.

I can't see well enough what he's doing down there by the wood. Is he rubbing it , holding it againsy=t the wood flat?    

[peternap]

Sharpening on a rag wheel is pretty common with knife makers. I have an extended arbor and have 4 wheels packed together. It helps keep things even.

He isn't rubbing on wood, There is a long piece of leather nailed (I assume under the bench, side to side) It is probably charged with buffing compound and he's just using it to strop off the wire edge.

[Don_P]

You can find rag wheels and emery compound at the big box, this is a great way to polish an edge. I keep a soft friable white wheel on the left side and a rag wheel charged with emery on the right side. For most edge tools I'll hollow grind to a wire edge on the grinder. If you watch carefully youll see a slight burr roll up when the grind gets to the edge, you can feel it if you stroke the edge from the back toward the edge. Use light pressure, a soft wheel and short bursts to avoid burning the steel while grinding. I then move to a diamond honing stone riding on the front edge and the heel to microbevel and remove the initial burr. Then I polish on the charged muslin wheel. Barring damage I'll hone by hand and rag polish many times until the hollow is almost gone then I'll regrind a hollow and start again. Even planer knives freshly back from the sharpener will last much longer if you polish them first.

The way to tell when an edge tool is dull is to hold it edge up in a strong light. If you see any reflection, a white spot or white line shining back from the edge, it is dull. A sharp edge parts the light on each side, there is nothing to bounce the light back at you.