How do you sharpen a ceramic knife?

[Will Carry]

  I bought my wife a Boker ceramic kitchen knife that “never needs sharpening”.  It’s as dull as a butter knife.  I tried using my Lansky sharpener with a diamond encrusted stone. Two hundred strokes on each side and it’s still dull!  I guess I can try two hundred more…….

[Ted S.]

Maybe the lansky stone is not abrasive enough to start sharpening it? I love the lansky system for pocket knives, but perhaps it is not aggressive enough for ceramic?

[TGO David]

http://www.boker.de/us/warranty.html

 

Due to their extreme hardness, which is why they do not need to be sharpened as often as a steel blade, they are brittle. Therefore, blade breakage or chipping is not covered under warranty. We do provide a sharpening service, which can get out most small chips in the blade and restore the original edge.

 

Do not attempt to sharpen your Ceramic knife on your own.

 

If you need to have your knife sharpened, please refer to the information below.

 

Send your knife to:

Ross Cutlery
Attn: Ceramic Sharpening
324 S. Broadway
Los Angeles, CA 90013

 

The charge for this service is $19.95 plus $10.00 for each additional knife in the same package. This service will take approximately 4 weeks.

 

Payment to Ross Cutlery must be in the form of a check or money order made out to Ross Cutlery. Please include a note with your name, address (no PO Boxes please) and phone number.

 

If you have any questions, please call (303) 462-0662 ext. 121.

[Will Carry]

Thanks for the feedback but for $20 and the trouble, I’ll try two hundred more strokes. My wife has a set of Almar knives and a couple of high dollar Japanese knives that I can sharpen. If I mess up the blade on the ceramic knife…. I’ll use it to spread peanut butter. ;)

Edited December 24, 2013 by Will Carry

[MacGyver]

This will sound odd to those whose last conversation about hardness was in 4th grade science class, but the zirconium oxide variants that most ceramic knives are comprised of is actually harder than a natural diamond.

Two hundred more strokes isn't going to help.

[dralarms]

I can't figure out how you dulled it. I got one I use all the time and cut partially frozen meat with it. I love mine. Just dont stick it in the dishwasher.

[Will Carry]

This will sound odd to those whose last conversation about hardness was in 4th grade science class, but the zirconium oxide variants that most ceramic knives are comprised of is actually harder than a natural diamond.

Two hundred more strokes isn't going to help.

 

We didn’t learn that in 4th grade. I don’t even think zirconium oxide was invented when I was in the 4th grade.  After reading some reviews on Amazon, it seems I am not the only one to complain about the sharpness of these knives. Maybe I was expecting too much. I also Googled Zirconuim Oxide. Your never too old to learn. 

[peejman]

This will sound odd to those whose last conversation about hardness was in 4th grade science class, but the zirconium oxide variants that most ceramic knives are comprised of is actually harder than a natural diamond.

Two hundred more strokes isn't going to help.

Ding!

You need a specialized grinder to sharpen it. A traditional sharpener will just rub on it. You'll do more damage to the sharpener than the blade.

[jimmydeuce]

Mine made it about 2 years before it started to get dull. I knew you weren't supposed to sharpen them but I tried anyway. Chipped it all to hell.

[Dustbuster]

I always wondered about ceramics, harbor freight sells 2 different models that have held up well for the past year 15 bucks each. Never tried to sharpen them as someone had mentioned to me there was a trick or method just for ceramics...I guess the easiest is to trash and buy again...


Sent from my iPhone using Tapatalk 2 of course it ate my spelling.

[Troutburger]

My wife's set is dull too. Lasted about 3 yrs.

[willis68]

I have never owned a ceramic knife and doubt that I ever will, too much trouble in my opinion

[mikegideon]

I have never owned a ceramic knife and doubt that I ever will, too much trouble in my opinion

 

The reason for their existence goes way over my head. Let's make a knife out of knife sharpening material. That's the ticket :)

[tnhawk]

  I bought my wife a Boker ceramic kitchen knife that “never needs sharpening”.  It’s as dull as a butter knife.  I tried using my Lansky sharpener with a diamond encrusted stone. Two hundred strokes on each side and it’s still dull!  I guess I can try two hundred more…….

If a Lansky sharpener won't do the task, I don't think it can be done at home.  I'd send it for sharpening or buy another knife depending on the value.

[gregintenn]

I can't figure out how you dulled it. I got one I use all the time and cut partially frozen meat with it. I love mine. Just dont stick it in the dishwasher.

What's a dishwasher do to a ceramic knife?

[dralarms]

I think its the banging around with other stuff. Not sure.

[gregintenn]

I think its the banging around with other stuff. Not sure.

Probably so. I've never had one, but thought the cutting edge would have to be prone to chipping.

[dralarms]

They are. But until you chip one you can peel a tomato and make the skin feel naked. Lol

[mikegideon]

Probably so. I've never had one, but thought the cutting edge would have to be prone to chipping.

 

It's the main reason they don't max out the hardness when they heat treat blade steel. Brittle ain't a good quality for a knife edge, and I don't know how you can avoid it with ceramic.

[Spots]

[quote name="mikegideon" post="1084661" timestamp="1388113027"]It's the main reason they don't max out the hardness when they heat treat blade steel. Brittle ain't a good quality for a knife edge, and I don't know how you can avoid it with ceramic.[/quote] Yep. When you harden steel by heating and quenching its extremely hard and will hold an edge forever. But if you drop it on concrete or ding it against something it'll crack or possibly shatter. So you have to temper them down to a managable rockwell. Thats the reason I don't own a ceramic. I have never seen one any sharper than a well sharpened high carbon steel knife. By well sharpened I mean scalpel/straight razor sharp. Tapatalk ate my spelling.