CBN Rods

[Cliff Stamp]

Grams or pounds?

[AKWolf]

Here is a link to the CBN rods, I don't know if it is erroneous or not.

http://www2.knifecenter.com/item/SP204C ... s-set-of-2

[SolidState]

Here is a link to the CBN rods, I don't know if it is erroneous or not.

http://www2.knifecenter.com/item/SP204C ... s-set-of-2

They are definitely listed in my dealer catalog, so they're real.

[Cliff Stamp]

It would be interest to see as people get these :

-the kind of effect it makes on the initial sharpening time
-are they used in the regular sharpening

I have been carrying one in the tube as a utility file/sharpener, it works maybe better than you might think.

[Cliff Stamp]

Update :



The knife on the right is a custom from Kyle Bettleyon :

-CTS-XHP at 63 HRC/Peter's

The edge was a little uneven, less than 20 dps on one side, less than 25 dps on the other. The edge thickness is between 0.002" to 0.008" (it gets thicker towards the tip). The blade has a deep hollow primary grind, relief style not "T" style.

This would not be trivial to sharpen on the medium rods because even the 20 dps setting will not hit one side and thus all that would happen is that a burr would form strongly on one side and never get removed on the other until you did thousands and thousands of passes. Most people would simply not sharpen the blade, however it is easily tamed by the CBN rods. It took 330 passes total to get both sides of the edge cleanly apexed at 15 dps, at that point it can be sharpened / maintained on the 20 dps setting with the medium/fine rods and as required just use the CBN at 15 when the 20 dps bevel gets so wide that sharpening slows down.

[sal]

Thanx Cliff,

Are you using water on the rods?

sal

[Mike157]

Good, straight forward, useful information. Thank you Cliff. Mike

[Cliff Stamp]

Are you using water on the rods?

Sal, I used to use water on diamond stones and used to recommend it, but I got some feedback about rusting when people would leave the stones wet and if you are not careful this can damage the surface of finer stones especially. As of late I have been using WD40 on diamond stones and the CBN. The main reason is to control the dust released, but as well to prevent damage to the edge in extremes by providing a slight lubricant. There are lubricants made especially for diamond abrasives but I have not used them, feedback in general is +/- on them (some people complain they are too thick/gummy).

[Bill1170]

Thanks, Cliff. Very useful information in this entire thread.

Bill

[Cliff Stamp]

As an aside, glass cleaners are often recommend when people discuss using the commercial products such as the Trend lapping fluids because the glass cleaners cost 1/10 the price and in general have positive feedback. I have used glass cleaners to clean diamond stones and remove rust and grime, but not use them extensively as a lapping fluid. No matter what you use, care has to be taken to watch the bond because many plate type stones can become unbonded when exposed to various chemicals.

[Blerv]

Hi Cliff,

Like the foaming non-ammonia kind? Great tip, thanks :)

[Robert Ptacek]

In what way is the CBN rods superior to the diamond?

[Cliff Stamp]

In what way is the CBN rods superior to the diamond?

In industrial applications, diamond is not used to grind ferrous metals (like steel) because it generates too much heat and suffers from diffusional (carbon) wear. There are claims that the same thing happens in regular hand honing, however I have not seen any evidence of this and the claims are often just assumed to be from the industrial results. However the industrial grinding is done with far more speed/force than using a diamond stone by hand so it isn't obvious that extension is true.

[Mjc1973]

What is diffusional carbon wear?

[Cliff Stamp]

What is diffusional carbon wear?

Diamond is made of carbon, in high speed/force grinding, the carbon from the diamond actually moves directly into the iron as carbon will dissolve into iron.

There is growing research into making steels which are resistant to that because if you could eliminate it then diamond would be a very nice abrasive for steel as it is so hard. For example : http://aspe.net/publications/annual_201 ... a/3011.pdf

[sal]

So Cliff,

What do you think of a "Double Stuff" (1" X 5") CBN on one side and ultra fine ceramix on the other side?

sal

[Cliff Stamp]

What do you think of a "Double Stuff" (1" X 5") CBN on one side and ultra fine ceramix on the other side?

Sal, I am not sure if CNB in the same grit as used here can transition to a UF ceramic even if using a micro-bevel, I will check the weekend. I know you can jump from the CBN to the medium rods easily with micro-beveling, even on hard to grind steels. I would wonder about the practicality of a triangle rod (CBN, medium, UF ceramic) or a square one with all four grits.

[JNewell]

Diamond is made of carbon, in high speed/force grinding, the carbon from the diamond actually moves directly into the iron as carbon will dissolve into iron.

There is growing research into making steels which are resistant to that because if you could eliminate it then diamond would be a very nice abrasive for steel as it is so hard. For example : http://aspe.net/publications/annual_201 ... a/3011.pdf

Wow, even at the sort of (non-)speeds that you'd get with, say, diamond rods on a Sharpmaker?

[Chris_H]

So Cliff,

What do you think of a "Double Stuff" (1" X 5") CBN on one side and ultra fine ceramix on the other side?

sal

Sal, I am not sure if CNB in the same grit as used here can transition to a UF ceramic even if using a micro-bevel, I will check the weekend. I know you can jump from the CBN to the medium rods easily with micro-beveling, even on hard to grind steels. I would wonder about the practicality of a triangle rod (CBN, medium, UF ceramic) or a square one with all four grits.

What about a double-sided pair -- mix the Double Stuff and 701MF designs? You'd have four grits on two stones in a leather slip case to hold both stones.

[Mjc1973]

Thanks Cliff. I used to work in the refractory industry and am still interested in the material sciences.