Ceramic Knife - Sharpening?

[NoAlibi]

I recently got a new ceramic knife and I'm not impressed with the sharpness of the blade.

Can they be sharpened in the conventional manner with stones? Is there a special technique to get the job done?

Thanks.....NoAlibi

 

[ArfinGreebly]

No

Do not attempt to sharpen using conventional methods or sharpening tools.

If it's a Böker, the factory will sharpen it for you.

What brand is this knife?

 

[hso]

Have you tried cutting with it or are you just testing the blade? Ceramics can feel different and still cut like a razor though the materials they're designed to cut.

As to sharpening, like AG said you can't use a stone or ceramic rod. You'd have to use diamond. The recommendation with all ceramic blades is to send them to the manufacturer for sharpening.

 

[NoAlibi]

ArfinGreebly - It's a Boker.

The instruction sheet does state to send it back for sharpening, but I didn't want to be without it during turn around time.

I have a diamond wheel - any recommendations?

hso - I tried cutting a tomato (the cat hauled butt when she saw the gleam in my eye) with it and it was noticeably inferior to a micro-serrated blade designed for the task. Should I wait for dinner and try it on a steak?

Just so I'm not being too picky, what would be a good test for blade sharpness?

 

[hso]

If a ceramic knife won't cut a tomato cleanly and nearly effortlessly then it should go back to the store/manufacturer for exchange.

 

[Gordon]

Ceramic knives are almost impossible (never say never!) to get shaving sharp. But they can be plenty sharp enough to cleanly slice tomatoes! A Diamond EZ lap board does it with a little time, but don't think you are gonna reprofile the blade!

I have an older Boker folder from about 20 years ago and a couple Mad Dog Mirages that I have successfully sharpened with a Diamond EZ lap board.

 

[NoAlibi]

Gordon - I don't want to reprofile it, I just want it as sharp as I've heard stories about them. I also didn't want to shave with it, but I wanted to be able to! So goes another ceramic knife myth???

Where can I find the Diamond EZ lap board? Do you use the same technique of moving the blade into the board as a steel knife into a stone?

Do you think a slowly rotating diamond wheel would do the job?

 

[hmphargh]

Just send it back or in the very least have it professionally sharpened by someone with experience with ceramic knives. Ceramic knives don't sharpen like steel, the ceramic kind of chips/flakes off and if you sharpen it incorrectly, you can easily make a blade useless and difficult to nearly impossible to repair. I learned this the hard way albeit with a cheap ceramic knife that probably shouldn't have been purchased in the first place.

 

[militaryknives]

There are few things more frustrating and dangerous than working with a dull knife. Ceramic material has the hardness of glass which is much harder than steel. But unlike glass, ceramic is abrasive. And it is this combination of abrasive hardness that makes ceramic such a good knife sharpener.

 

[mete]

The ceramic blades have to have a larger angle than you can get on a steel blade. Sharpening a ceramic is possible but not worth the trouble send it back. The edge must be polished so there are no scratches as scratches may cause fractures ! I'll stick to steel .

 

[NoAlibi]

The knife has been packed and shipped back to Boker.

As several of you have suggested - I'll stick to steel.

Thank you all for your input.

 

[HoosierQ]

Ceramic knives seem to be a solution to a problem that wasn't there.

By almost all accounts, flint knives, when new and done well are actually much sharper than steel but they are not nearly as durable. In America, the native people wanted steel knives not because they were sharper but because they were more durable and could be resharpened.

In the amazon, they used split bamboo knifes. When first split, the slivers of bamboo are as sharp as razors. Of course after cleaning one fish or skinning one possum or whatever it is dull and they throw them away...lots of bamboo in the jungle right at hand.

So I am sure that a ceramic knife can probably be made sharper at the factory but after that...

 

[nalioth]

The instruction sheet does state to send it back for sharpening, but I didn't want to be without it during turn around time.

So buy another one and alternate them in your usage patterns.

 

[NoAlibi]

nalioth -

So buy another one and alternate them in your usage patterns.

I thought about what you said and if I was truly enamored with the knife your solution would be the way to go.

The knife was a gift and I liked the novelty of it, but truthfully it doesn't handle, have the looks or functionality of my steel knives. When I get it back it will probably see only occasional use and reside in the dresser as a "draw queen".

 

[highorder]

Ceramic knives seem to be a solution to a problem that wasn't there.

I agree. They aren't sharper, cheaper, more durable, more useful, better looking...

All they are is different. And not in a good way.

 

[CWL]

Was this a Boker folder or a Kitchen knife?

A ceramic kitchen knife should be able to slice tomatoes thin-enough so that you can lay it on a newspaper and be able to read the type underneath. (Doesn't mean that this makes it a better kitchen knife than steel though.)

I don't think a folder would be able to do it as easily because the angle of the grind is much higher. You will need to develop a light sawing motion with such a short ceramic knife to be able to cut soft materials like fruits & veggies.

 

[NoAlibi]

CWL - It's a folder. I used a tomato as a test because I expected it to do as well as the paring knives I seen used. Thanks for your input.

 

[nalioth]

Ceramic knives seem to be a solution to a problem that wasn't there.

I agree. They aren't sharper, cheaper, more durable, more useful, better looking...

All they are is different. And not in a good way.

Oh, I wouldn't be so quick to discount them. They have a property no steel knife can match - they're non-reactive.

This means they don't cause brown spots on fruits and other items.

 

[Gordon]

ANDthey make a heck of a neck knife!

 

[highorder]

This means they don't cause brown spots on fruits and other items.

I understand the concern, but I've never had a problem.
I don't use carbon steel knives, and my stainless knives don't seem to react.

Mom got me one of those plastic lettuce knives. I used it once to cut some lettuce.
Maybe I should eat more lettuce?

 

[7X57chilmau]

Carbon steel knives will discolour some veggies and fruits.... If you cut quickly enuf, not much of a problem!

SS knives don't suffer from it, in my experience... Can't see a reason for a ceramic knife, so I haven't bought one. Some people love'em. All is as it should be

J

 

[DAVIDSDIVAD]

I reprofiling a ceramic knife on a belt sander once, only to have the section I was doing explode.


Lucky I was wearing a heavy canvas apron, goggles, and mask.





I said the same thing 7x57, but those ceramic knives are just FUN!

They feel strange in the hand, in a good way.

 

[7X57chilmau]

Yeah, I really want one, but can't seem to want one quite enough to actually buy one.....

Until then, I'll illustrate my jealousy by scoffing at'em at any opportunity

I'm a weak man.

J

 

[nalioth]

Well, you guys know that Harbor Freight Tools sells fixed blade ceramic knives (most likely the same kitchen knives sold under "name brands") at their thousands of stores. .

 

[7X57chilmau]

Didn't know that.... Never been to an HF.... Princess Auto, near as I can tell a similar store, doesn't offer one...

I figure a 9.99 knife is probably worth that, though.....

J