# Would an electric Sharpener Ruin The knife?



## donbuyyo (Nov 10, 2013)

Hi,

I have and I am thinking about buying a Chef's Choice 1520. From the reading I have done on here it seems that an electric sharpener might not be suitable but its rather a grey area. What are your thoughts?


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## dillbert (Jul 2, 2008)

having seen multiple acquaintances totally trash decent (read:  expensive) knives with electrics, I would not let an electric within grid length of my knife block.

if you search back in the Forum, you'll find "acceptance" of (I think only...) one "brand" - it's completely inflexible, and imho only works in the hands of an experienced to expert sharpener.

so basically, unless you're already an expert in sharpening and already have 'the touch,' odds are using it will cause uncouth damage to the knives.


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## chrismit (Nov 18, 2012)

I'm going to disagree with dilbert, I own a chef choice trizor and also sharpen by hand. I also own a Mac Pro and in the past used the chef choice on the Mac. It is not hard to use as long as you use a light touch it works fairly well. Sharpen a cheaper knife or two first and you'll be all set. It's not in the same category as stones and the heel can give you some problems but if its between being sharp and not its not even a question. Some people will tell you it takes off way too much metal, not true. Maybe a small amount more than stones but nothing substantial. I would always encourage you to learn hand sharpening but if thats not in the cards the chef choice will do a decent job


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## dillbert (Jul 2, 2008)

>>I own a chef choice trizor and also sharpen by hand.

what's to disagree?  you already have sharpening skills, which is what I said.

if you know enough to know aalread what a 'light touch' is - you won't be putting divots in the middle of the blade....

(some) electrics may be okay - if and when properly used.  otherwise they are 'the destroyer of blades'


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## chrismit (Nov 18, 2012)

I now have sharpening skills but did not when I regularly used the chef choice. It does not take an experienced or expert sharpener to use the machine. Let the knifes weight do the work and you will have no problems


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## rat (Mar 2, 2006)

Benuser hit the nail right on the head, its all the geometry, higher end electric sharpeners work just fine for my chroma knives.


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## bottomofbachelo (Jun 16, 2015)

Thanks for all who have contributed thus far to this post. I wanted to get some opinions on a sharpener out there. I've spent TOO long researching this and now I think I've reached the point of information overload.

In searching I eventually came across Benuser's comment about geometry. So does an electric sharpener that allows you to select the blade angle sound like a good solution? I found a review of one here, but I'm still not sold. Has anyone used this particular model before? Is there a better model out there?

I've also looked at some of the sharpening systems from Edge Pro and they look like a good solution. Any help is greatly appreciated.


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## knifeforhire (Jun 16, 2015)

I have used every model of ChefsChoice they have ever offered. Once you set the primary edge bevels created by the first stage wheels, stay off of them as much as possible. Oonly use the second and third stages (some models only have two stages) for touch ups. Often, all you need is the third stage and it takes very little metal off a blade. Most of the time I hand sharpen but if I have a big job coming up and need to sharpen a number of knives at once, the ChefsChoice pro model comes out.


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## foodpump (Oct 10, 2005)

Where I take issue with 'lectric sharpeners is with the word "electric".....

See, if you hone a knife by hand you are moving at maybe 15-20 rev. per min.  With a 'lectric one you are moving the abrasive or the knife at much higher rpms.

What this really means is that you are removing much more steel with a 'lectric device compared to a manual one.  If you use an electric device multiple times a week, your knives will shrink at an alarming rate....

That is not to say electric machines don't have their place.  They do, but not with honing, rather with massive amounts of metal removal:  Like to grind out a bad nick or to re-establish a bevel, that's what they do best. Then hone by hand.  You'd be there all night if you tried remove a nick by hand.

But for daily honing and light touch-ups, I stay away from electric appliances, I don't need any more boning knives.....


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## dcarch (Jun 28, 2010)

The biggest problem with an electric sharpening device is that  it can permanently, instantly and irreparably destroy the temper of the thin thin edge  by over heating.

You wouldn't even know that it happened.

"Why my expensive knife wouldn't hold a sharp edge? Must be the fault of the manufacturer!"

dcarch


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## knifeforhire (Jun 16, 2015)

I know those combination can opener/knife sharpeners sometimes over heat blades but I've never known a ChefsChoice machine to do that.  I've also used the professional model Master Grade machine. It seems to warm the blades up a little but the maker insists it will never over heat them. He wasn't very happy with me for even suggesting it would.


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## dcarch (Jun 28, 2010)

Knifeforhire said:


> I know those combination can opener/knife sharpeners sometimes over heat blades but I've never known a ChefsChoice machine to do that. I've also used the professional model Master Grade machine. It seems to warm the blades up a little but the maker insists it will never over heat them. He wasn't very happy with me for even suggesting it would.


There is no way you can get around the law of physics. You move metal quickly, you will generate heat. Thin knife edge has extremely low thermal mass, and it can get hot quickly.

Unless you us water to lubricate and to cool.

As I said you may not even know that your knife edge has been de-tempered. You can't tell if it happened. most of the time the oxidation discoloration gets removed by the grinding.

dcarch


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## knifeforhire (Jun 16, 2015)

And this has happened to you on the ChefsChoice Dcarch?


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## dcarch (Jun 28, 2010)

Knifeforhire said:


> And this has happened to you on the ChefsChoice Dcarch?


I don't have a ChefsChoice. However, I do use a belt sander and a motorized grinding stone to sharpen some of my knives.

I can do that without too much problem because I made many of my knives using D2 tool steel, which is very heat resistant.

The other knives I use my hand stone sharpening system.

dcarch


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## foodpump (Oct 10, 2005)

I just dunno about this....

I see any motorized abrasive as a course metal removal tool, not at all ideal to put a finished edge on a blade--in much the same way as a cement truck is not ideal to go on a date with...

As a side line, I pick up chisels and other woodworking tools at fleas and garage sales and "fix em' up".  More often than not the edge is beyond toast, and has been used as a paint can opener.  This is where the powered grinder--even one @3450 rpm can be usefull--to grind a new bevel on.  If you leave the chisel in one place or press hard, you will get hot spots and ruin the temper, if you move the chisel or tool fairly quickly and with light pressure, either dunking it in water or grinding another tool in between, you are more than likely not to get hot spots.  Same thing with plane irons which are usually in the 2-21/2" widths.  In the case of a well sharpened blade with a nick in it, the usual protocol is to "dub" the edge, or grind off the edge so you can re-establish a new bevel past the bottom of the nick.

Most knives, however are anywhere from 6-10" long, and if you use light passes and move the tool fairly quickly, you are not likely to get hot spots.  There is no way you will get a sharp edge on a blade with just a grinder, as you are almost guaranteed to burn the edge, the grinder is only there to establish the bevel, the removal of the grinder's grit pattern and honing should be done by hand.


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## knifeforhire (Jun 16, 2015)

"Sharp Edge" seems to have a lot of different meanings to different knife users. If you mean sharp enough to make thin slices off a ripe tomato or shave the hair off your arm with ease, yes the ChefsChoice machine will do it with ease.


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## millionsknives (Apr 25, 2014)

OP: If you're real careful, you can have a knife that's simply damaged and not ruined.


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## dcarch (Jun 28, 2010)

Knifeforhire said:


> --------------------. If you mean sharp enough to make thin slices off a ripe tomato or shave the hair off your arm with ease, yes the ChefsChoice machine will do it with ease.


That is very true. Because you can have almost any metal sharpen sharp enough to shave hair, including aluminum. The question is how long can the edge remain sharp after you damaged the temper of the steel.

That is why I think it is meaningless to see those demos of slicing paper, slicing tomatoes and shaving hair.

dcarch


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## dcarch (Jun 28, 2010)

MillionsKnives said:


> OP: If you're real careful, you can have a knife that's simply damaged and not ruined.


You can be very careful 100 times. But that one single time you didn't pay attention on one spot along the edge, there goes the value of your knife.

dcarch


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## knifeforhire (Jun 16, 2015)

Gee, I must have been one lucky son of a gun for the last 20+ years then. Trust me on this, I own and have used every type of sharpening stone and gadget out there as part of my profession. My basic opinion is the ChefsChoice is a good machine for those that don't know how to hand sharpen or are too busy to do that on a regular basis.  Belt sanders (I have one) and this little electric sharpener are apples and oranges.


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## dcarch (Jun 28, 2010)

Speaking of apples and oranges:

You have 20 years of experience, and OP has 0.

Is it surprising that you have better luck with a motorized sharpener?

dcarch


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## millionsknives (Apr 25, 2014)

The right tool for the job is a whetstone. The faster right tool is a wet grinder. Grizzly 10" is $200 and 8" is $100, even less than a chefs choice!


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## lasagnaburrito (Jun 9, 2015)

This is an interesting thread, I learned a lot...

Can someone explain more about what "temper is" and how we go about NOT messing it up?  From what I've read it seems that if you screw it up, you're basically screwed?  So you can't fix it?


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## dcarch (Jun 28, 2010)

Tempering, without going into the science:

Steel (or stainless steel) is very ductile and somewhat soft. It is first cut, forged, heated to red hot and hammered into a knife shape. Then it is ground to have a rough edge, a very dull edge.

At this point it is subject to very high heat and then a very sudden cooling to harden the metal. After hardening the metal is hard but very brittle. It is then tempered slowly in low heat to reduce the brittleness. After the tempering, the dull edge is carefully and skillfully ground and polished into a useful sharp knife.

It you heat up the edge too much, you will *permanently* destroy this entire process.

dcarch


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## lasagnaburrito (Jun 9, 2015)

Thanks for that!


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## dcarch (Jun 28, 2010)

Benuser said:


> Only solution would be to have the heat treatment repeated.


Generally no.

You have to first disassemble the knife to remove the handle, then any unevenness in the grind of the knife will cause the blade to twist, bend and warp.

The very fine edge and thick spine of the blade results in severe differential shrinkage of the metal during hardening and often cause the blade to spontaneously crack.

dcarch


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## chef le grande (Jun 21, 2015)

I say yes, sorry. if you learn how to use a steel you will have the best sharpener in the world, your hands!


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## lasagnaburrito (Jun 9, 2015)

I guess the next question would be what are the "preferred" methods of sharpening?

There are multiples kinds of stones,

there are honing tools,

And then I've seen leather straps too (forgot the name I saw, started with an 'S').


Thoughts?


Sorry to thread hi-jack, figured it would be good info for all!


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## Iceman (Jan 4, 2011)

Were any of you guys ever in the _"Boy Scouts"_?!? I remember learning how to sharpen knives. If you do it correctly ... good for you. You have a good working knife. If you do it wrong ... too bad. After a while you either get another knife or you stop playing with knives.

Electric sharpeners can ruin knives if you do it wrong. You know what ... stones, even very good stones ... can also ruin knives if you do it wrong.

Learn how to do things correctly and you don't ruin your equipment.

_(duh)_​


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## ed buchanan (May 29, 2006)

Depends on the type of machine. If your talking the kind purchased in dept. stores  forget it. If the old fashioned grinding wheel like the guys in the trucks use, if you know how to do it.   OK.


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## dcarch (Jun 28, 2010)

ED BUCHANAN said:


> Depends on the type of machine. If your talking the kind purchased in dept. stores forget it. If the old fashioned grinding wheel like the guys in the trucks use, if you know how to do it. OK.


Those machines use water as coolant.

dcarch


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## pcrcrepaira (Jan 31, 2016)

The electric sharpener probably uses a motor to turn a grinding wheel. Putting a knife on a wheel will burn the carbon out of it, making the edge last only a few cuts instead of a few weeks. You need to sharpen metals slowly to avoid burning the metal so the carbon is retained and the blade's hardness isn't affected. You can do this by using a hand sharpening method of some sort, OR you can get one of those grinders with a wheel that turns really slow and is dipped in water to keep the metal cool all the time. You will have to set the angles on the tool rest as closely as possible and have a steady hand to do it, but it can be done. These grinders are sold for grinding woodworking chisels and run around 100 bucks or so. Use a fine grit wheel turning in water for good results and a good tool rest that doesn't move to assure the angle doesn't change. The finer the wheel, the longer the edge will last if you take care of your knife .


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## phatch (Mar 29, 2002)

pcrcrepaira said:


> The electric sharpener probably uses a motor to turn a grinding wheel. Putting a knife on a wheel will burn the carbon out of it, making the edge last only a few cuts instead of a few weeks. .


Um, no. The carbon doesn't really burn out of it. You can mess with the temper certainly. But it's not really about using a motor alone. If you have good technique, a motorized tool will work fine. Keep the knife moving so it can't build up enough heat to mess with the temper, it works fine. A skilled worker at a slack belt on a belt grinder can produce an amazing edge. A buffing wheel with some Black Magic Compound will make it scary sharp.


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## payton29 (Feb 6, 2016)

I would say yes but it just mostly depends on the person who's doing it. just my 2c


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## bottomofbachelo (Jun 16, 2015)

First I'd like to thank everyone that has contributed to this topic. Previous to reading this thread I had used a Chef's Choice for sharpening my kitchen knives. I know for a fact that I never got great results. Between the guide magnets grabbing at the blade while drawing it through, the inconsistent speed (my fault), and variable pressure on the knife I generally ended up with a blade that stayed sharp for a few uses at most.

After reading all of this and some other resources online (such as http://www.jayfisher.com/Knife_Care.htm#What_about_powered_sharpeners_and_systems), I started looking for a way to easily sharpen with stones that didn't require the learning curve. I stumbled on this (http://www.thetoolreport.com/top-rated-knife-sharpeners/) which actually discusses a good bit of what has been said here. I settled on a Edge Pro Apex system and I must say I have been very happy with it. Manual operation with stones and no heat.


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## millionsknives (Apr 25, 2014)

bottomofbachelo said:


> I settled on a Edge Pro Apex system and I must say I have been very happy with it. Manual operation with stones and no heat.


And removes much less metal


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