Sharpening a ceramic swivel knife

[Gabriel Rasa]

Basically: is it necessary?

I keep seeing people on youtube and whatnot stropping their ceramic blades before use, but I've been using the same ceramic filigree blade for all the work I do for... eight years now? Haven't stropped or sharpened it once, and the only time I notice it dragging is when the leather is cheap and spongy and/or badly cased. Would I be getting better results if I did? Or are the youtubers stropping unnecessarily?

[DJole]

Good question -- if you have never stropped it, try the experiment: cut without stropping, then strop it and cut again, and see if it makes a difference.
The material differences between metal and ceramic might come into play here, but I'm just guessing. 

[Rhale]

I’ve only used one years ago and didn’t use a whole lot then but I remember that stropping seemed to help quite a bit!

[Gabriel Rasa]

7 minutes ago, DJole said:

Good question -- if you have never stropped it, try the experiment: cut without stropping, then strop it and cut again, and see if it makes a difference.
The material differences between metal and ceramic might come into play here, but I'm just guessing. 

I was never great at stropping even when I did use a metal swivel knife -- I was never sure which jeweler's rouge/compound I was supposed to be using, and couldn't actually tell whether it was making a difference. (Though if anybody can weigh in on that, I'm sure I've still got all the stuff kicking around somewhere.) When I'm sharpening razor blades I use a regular whetstone, and I've found that finishing it off with a ceramic whetstone makes a world of difference in how smoothly it cuts, but I'm guessing you can't sharpen a ceramic blade with a ceramic whetstone. =/

[YinTx]

I looked at my ceramic blade under a 10x loop, and could see grind marks from the factory.  I "sharpened" it (ie, removed the grind marks and got a nice polish on it) and now no drag.. at. all.  Strop once in a while if I feel like it, but with white rouge on a piece of cardstock, not leather.  I think I used a Cerax stone to hone, but don't remember.  Possible I used some sand paper because I didn't want to damage the stone.  But they will take a shine like glass if you work them.  Unfortunately, mine has an old crack, so I can only use the one side, which means I usually pick up a metal blade as a favorite.

YinTx

[Gabriel Rasa]

3 minutes ago, YinTx said:

I looked at my ceramic blade under a 10x loop, and could see grind marks from the factory.  I "sharpened" it (ie, removed the grind marks and got a nice polish on it) and now no drag.. at. all.  Strop once in a while if I feel like it, but with white rouge on a piece of cardstock, not leather.  I think I used a Cerax stone to hone, but don't remember.  Possible I used some sand paper because I didn't want to damage the stone.  But they will take a shine like glass if you work them.  Unfortunately, mine has an old crack, so I can only use the one side, which means I usually pick up a metal blade as a favorite.

YinTx

Aha, this is what I was after! What did you use to remove the grind marks? Was that the sandpaper? I'm assuming you used a super fine grain?

[YinTx]

yes, I probably started at 600 grit and worked all the way to 2000 grit before polishing with rouge.  It's been a while since I did it, but I was really happy with the outcome.  Use a high quality 3m paper if you can.

YinTx

[Dogwood]

Question for you, as the internet seems to be strangely vague on this - what are the advantages of ceramic vs. metal? I'm in the market to upgrade from my cheap, beginner no-name swivel and currently in the research phase. 

[YinTx]

1 hour ago, Dogwood said:

Question for you, as the internet seems to be strangely vague on this - what are the advantages of ceramic vs. metal? I'm in the market to upgrade from my cheap, beginner no-name swivel and currently in the research phase. 

Ceramic Pros:  Should already be sharp.  Should always stay sharp.  You will have to strop.  I found I had to sharpen and polish mine, so this pro went away.

Ceramic Cons:  Brittle.  Easy to chip or crack, once this happens, usually useless.  Mine has a crack, I can still use it though one side works better than the other for sure.

Metal Pros:  Easy to sharpen, easy to polish.  You can change the angle of the grind if you desire.  You will have to strop.

Metal Cons:  You will have to sharpen most common brand blades when you receive it.  The more expensive, high end brands will come already sharp, so this con goes away.  You may have to sharpen it again in your lifetime.  Usually stropping does the trick tho.

I have a small collection of swivel knives, and it is small compared to other's collections.  Everything I can do with an expensive blade I can do with my cheapest blade.  You could not have convinced me of this before I had my collection, because I was sure a great blade would change my world.  Yes, an expensive tool is wonderful to use.  Unless you just gotta have it tho, probably not worth the orders of magnitude price difference.  I still regularly pick up my old lower end Tandy swivel because I like the angle of the grind, and I managed to get a very good polish on the blade and it cuts very well.  Even Jim Linnell, who has an impressive array of vintage, collectible, and high end swivels always seems to pick up his Tandy Ergo swivel to teach his classes.

As an aside, Robert Beard will sharpen your blade for you for free for life (_his_ lifetime, not yours or the tool's!)  He has just done this for a blade that I picked up second hand that had  a bad regrind on it.  I have not put it to use yet, I am still hoping that it will change my world, so my assertion that no one can convince me that a cheap blade will do the trick even if it is true, still holds.

YinTx 

[JayEhl]

On 2/24/2021 at 11:23 AM, YinTx said:

As an aside, Robert Beard will sharpen your blade for you for free for life

@YinTx  Can you share what contact method is best to make this arrangement?  

Edited August 4, 2021 by JayEhl

[YinTx]

If you find his facebook page, I think they list a phone number there for him.  I have found that to be the best way for me to reach him.

Also, I put it to use, many times since the last post.  It is phenomenal, I love it.  Still pick up my old Tandy on occasion, but I do enjoy using my Robert Beard swivel knife.

YinTx

[mrwatch]

Of ceramic knives, yes they are brittle, drop it once or hit something hard it may become useless. Only a very fine diamond hone will sharpen ceramic however you may find a leather strop on a piece of wood with compound could remove unseen micro particles of  leather or paper material stuck to the ridges. The original ceramic kitchen knives were undetectable by airport XRAY machines so they required them to have metal particles in the material. Your blade may not have them and I do not know the year this change came about. 

[YinTx]

5 hours ago, mrwatch said:

Only a very fine diamond hone will sharpen ceramic

I must say my experience differed from yours.  I did manage to sharpen mine with a high quality sand paper.  Just takes some patience.

YinTx

[mrwatch]

15 hours ago, YinTx said:

I must say my experience differed from yours.  I did manage to sharpen mine with a high quality sand paper.  Just takes some patience.

YinTx

Thanks, I was going by the best of kitchen cutlery like the Kyocera  Company brand which is more for cutting produce. The swivel knife may be made of a lot different materiel and I assume you meant wet or dry auto body sand paper and not flint sand paper for wood? 

[YinTx]

9 hours ago, mrwatch said:

I assume you meant wet or dry auto body sand paper

Yes, and with a lubricant (soapy water).  Takes some time and diligence, but it'll get er done.  Much smaller surface area to polish vs. a kitchen knife, too, so that helps.

YinTx

[TwinOaks]

Here's an older conversation that might be found useful...

 

 

[Garyak]

On 2/9/2021 at 7:05 PM, Gabriel Rasa said:

Basically: is it necessary?

I keep seeing people on youtube and whatnot stropping their ceramic blades before use, but I've been using the same ceramic filigree blade for all the work I do for... eight years now? Haven't stropped or sharpened it once, and the only time I notice it dragging is when the leather is cheap and spongy and/or badly cased. Would I be getting better results if I did? Or are the youtubers stropping unnecessarily?

Bought mine in 93. Still use them. Never stropped neither. 

[Frodo]

seek out a Swivel Knife Blade Sharpening Guide 8126

it will take the guess work out of keeping your blade sharp.

 

you mentioned you did not know which rouge to use

I like the green or the white.. either is fine.  

 

[Garyak]

On 10/19/2021 at 12:05 PM, Garyak said:

Bought mine in 93. Still use them. Never stropped neither. 

Same here, Same year. Bought two. Only used one. Still have the other, as well as The extra needle for my badger airbrush gun. I’ve never used the extra of either. Never had to strop or “sharpen”, and it’s never chipped on me. Crazy, when you take care of stuff it last, like the edge of a ceramic blade……. 

Edited November 15, 2021 by Garyak

[patmcf1]

On 2/9/2021 at 9:56 PM, YinTx said:

Use a high quality 3m paper if you can.

3M, at one time, made opthalmic sandpaper for use in polishing lenses for glasses, etc.  Maybe you can score some online somewhere.

[patmcf1]

Here's one place to purchase 3M polishing sandpaper...

https://www.stewmac.com/luthier-tools-and-supplies/supplies/sanding-and-polishing/sandpaper-and-finishing-papers/3m-flexible-polishing-papers/?utm_source=google&utm_medium=shopping&utm_campaign=2021-12-gp&gclid=Cj0KCQiAqbyNBhC2ARIsALDwAsBvtL1IcZSJKgs6hifG7l7ixBRXWPKPmHAaW_8Xlj1vwx3d-zgFT-UaAqpTEALw_wcB

 

[Davm]

I also make knives and use a green chrome rouge to polish to a mirror finish, so...I applied that to my strop.  IMHO if you are drawing the edge toward you when stropping the idea is to remove tiny burs and sucjh and the angle doesn't have to be quite as precise as when actually honing on a stone. Texas Knife makers Supply should have the green chrome.

[JayEhl]

Hi,

 

While here, I have a question about the polishing compound, more specifically what is the consistency supposed to be like? 

I know a few will cringe when I say I am still using the white compound from my starter kit from Tandy.  It is hard as a rock and I have to rub kind of aggressively to get it on my cardboard backing (what I normally use).    Should it be that hard?  And I've read somewhere that different colors offer contains different material used for the sharpening, but what color is best for ceramic v metal blades?  And what should the consistency be like out of the box, meaning, if it's supposed to be hard as a rock.

Thanks in advance.

[tsunkasapa]

I have three colors, white, red and green. And they are all fairly hard. Personally, I like the green. It is what my friends that make knives use.

[DrmCa]

What material are ceramic blades made of? (Please, do not say, ceramics!)

If they are made of anything like alumina then they can be stropped with tungsten carbide or boron carbide compound. If they are made of tungsten carbide then they can only be stropped with diamonds.

It would be a waste of time to try to strop an alumina blade on alumina-based or chromium oxide compound because their hardness is pretty much the same, and there will be nearly zero grinding effect.

TC tool bits can only be re-sharpened on a diamond wheel. They would chew through anything else.