Sharpening a serrated knife

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Joined Jan 7, 2018
Long story short, I found a beautiful serrated knife that I want to use but it's as sharp as a spoon. The issue is it's edge is the scalloped type of serration; very shallow waves, not the pointed and deep serrated sort that would be easily sharpened with a rat tail file or ceramic rod in said grooves. I figured I'd ask the more experienced folk over here on how to sharpen such a knife before I miss it up badly. Any ideas?
 
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I recently did that using slip stones that were wedge shaped with a rounded back. Found them on eBay.

It helped to have both a coarse and fine stone.

Like this example:
https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/162852855251

Search eBay and you’ll find this shape in several materials and grittiness.
I live on the other side of the planet :p
Ebay is not an option for now, and I can't find regular whetstones here let alone these ones, so thanks for the idea but it won't work for me :s
 
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You might want to consider updating your profile with a location, or be more specific about your limitations so we can better help answer your questions.

A rat tail file won’t work very well. Ceramic rod - Marne but it might be a very slow and laborious process.

Don’t you have a hardware or woodworking store wherever you live on the other side of Mars?
 
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Tapered wooden dowels of different sizes + sandpaper. Deburr other side on a stone.

If the serrations are too small for that, give up
 

phatch

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This is where the Spyderco Sharpmaker is a particularly useful device. Because it's stones are rounded triangles, they can fit fairly fine serrations and still work well with the more broad wavy serrations.
A bit pricey for only sharpening serrations but it can do a number of other oddball items for sharpening as well as regular sharpening work.
 

phatch

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Where your knife is so dull it might also be worth picking up an inexpensive round diamond hone in the 3/16 inch diameter range for the initial work.
 
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I've used the spider on v shaped stone-on-rod for serrated knives to good success. On the Forschner/Victorinox knives I just use a chainsaw file, as small as I can find. This does a great job, and chainsaw files are cheap and easy to find.
 
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What exactly, of anything mentioned here, is available to you on in the land of OZ? And how important is a bread knife to you anyways? And how about knives in general? JCK can ship to just about anywhere in the world.
 
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What exactly, of anything mentioned here, is available to you on in the land of OZ? And how important is a bread knife to you anyways? And how about knives in general? JCK can ship to just about anywhere in the world.

First off thank you all for the replies, was swamped yesterday and I only now had the chance to check the forum.
The spyder isn't available here, sadly. I live in Lebanon, and not the Pennsylvania town. When it comes to knives, people just don't care. Aside from some European overpriced brands (scanpan and such) at boutique kitchen cookware stores, no one seems interested to buy anything better than victorinox. I can find hones and such at hardware stores, so thats my only viable option from the above suggestions. As for me, knives are an obsession. I started cooking as a stress relied and I really got into kitchen knives. All my knives were purchased when I traveled to the US/Europe. Shipping to Lebanon is hell, and a very expensive one at that, too. A fujiwara 270 suji would run you around 200 dollars all things considered from JCK, hence I only buy when I'm tjete, and since I don't have any exchange programs for a while I won't be traveling for a while.
So that's knives in general, as for this knife specifically, it holds a lot of sentimental value, so yea I'd rather fix it up and use it.
 
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A conventional saw-chain file I would think tricky to use here, better a diamond C-S file will, or a medium and fine tool-makers version from an industrial supply.

The dowel and wet/dry sandpaper method is good, I should think you can get these things. Maybe start with 180 grit to get things thinned to near the cutting edge then go 360, maybe finish with 600.
 
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I saw a lot of people sharpening serrated knives with electrical sharpeners. How " safe" are those?
 
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Hi Rick,

Why don't you find out for yourself about using a chainsaw file? It is not difficult at all. I and many other people have been using a chainsaw file on serrated knives for years now. I also don't see why a diamond file would be "better". Both files and diamond stones are designed to remove metal.

So please, trot off to a hardware store, spend the 10$, and try it out on a beater knife-- it's a helluva lot cheaper than a specialized diamond file....
 
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Hi Rick,

Why don't you find out for yourself about using a chainsaw file? It is not difficult at all. I and many other people have been using a chainsaw file on serrated knives for years now. I also don't see why a diamond file would be "better". Both files and diamond stones are designed to remove metal.

So please, trot off to a hardware store, spend the 10$, and try it out on a beater knife-- it's a helluva lot cheaper than a specialized diamond file....


Examine the difference in angles of attack between serrated knife and CS tooth, and the nature of the file tooth and, hopefully, you will see why an ordinary CS file is a poor choice compared to the diamond file.
 
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Tell you what,

I'm a pastry chef. I use serrated knives almost as much as chef's knives. When a serrated knife gets dull I can either toss it and get a new one, or sharpen it myself. I know of no professional knife sharpening service that accepts serrated knives. The people I do know tend to sharpen a serrated knife like a regular double bevel knife, with the teeth getting smaller and more rounder--essentially as useless as an ashtray on a Harley for slicing bread or the like.

So, what I do is get a 16" hunk of tube-a-for (2 x4, a.k.a stud) cut a slit down the middle, insert the blade into this slit so the teeth are poking about 1/2" and clamp this assembly in my vice at home. This method is very similiar to sharpening a handsaw, which is pretty much what a serrated knife is

Then, you guessed it, I take a chain saw file and run it into each tooth gullet until I have removed enough metal to create sharp intersections at the edge of each gullet. I have no idea at what angle I file, but know it is consistent because the file rests on the 2x4 and the tooth gullet.

I am not slicing glass smooth sashimi grade tuna here, the serrated knife is a work horse I use to slice bread, sponge, etc. but more importantly the knife needs to be razor sharp for slicing biscotti and delicate sponge.

I have no idea about what you mean about "angle if attack", but my knives are sharp, my slices clean, and I haven't bought a new knife in years.

Like I said, get a chainsaw file and try it out on a beater knife, THEN comment on your experience.
 
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Fair enough, but you still haven't elaborated on the " angle of attack" thing.
Are you saying a file won't cut if presented to metal at a certain angle where as a diamond rod can?
 
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I think a conventional file will tend to bend the relatively thin knife edge away from the cutting teeth, especially as you are driving it perpendicular to the edge, as opposed to the parallel travel across the major cutting surface of the CS tooth. The diamond presents smaller and sharper cutting surfaces and less pressure on the edge, that's its advantage here.

It obviously adequate but the toothed file should do a much better job on the chain than on the knife.
 
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