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160,000 grit Knife Edge!- CBN emulsion on kangaroo

Thu Feb 14, 2013 5:19 am



In this video I demonstrate two products - a Kangaroo leather strop mounted on glass and a brand new product - CBN or Cubic Boron Nitride in a new formulation. This formulation is an EMULSION that is water soluble. CBN - the second hardest substance - nearly as hard as diamond and harder than the Vanadium carbides found in many abrasion resistant steels. Even harder than Boron carbide. Under certain conditions CBN is even harder than diamond. CBN also has the property of giving a more comfortable shave than diamond for straight razor users.

The grit is a 0.1 micron particle. This is a 160,000 grit abrasive! Superb to use on both knife edges and straight razors. I find it particularly nice following a 15,000 grit Nubatama Bamboo stone, a combination I recently did on a Black steel Nubatama yanagi, but you can use this following any high grit natural or synthetic stone or following coarser sprays like 0.25 micron diamond or CBN sprays. The edges produced exhibit superb cutting action, fulfilling the needs of someone requiring a 'toothy feeling' yet still giving superior push cutting performance.

I begin by putting on a cheap exam glove (available at Costco by the box). This keeps the emulsion from absorbing into the skin (harmless), letting you spread it around further until it absorbs into the leather. Absorption is very fast and lets you immediately begin using it. The compound adheres VERY firmly to the leather, making this formulation particularly good for powered applications like leather belts (belt grinders) and buffers. It also works quite nicely on nanocloth and linen. I designed this formulation specifically for Kangaroo leather, however it works remarkably well on all the surfaces I mentioned. On nanocloth it lays down a very heavy coating. You could use it on felt or balsa, but Kangaroo and Nanocloth are the finest surfaces.

After applying the emulsion and letting it dry - almost immediately - I strop a Spyderco Manix 2 with a CMP-M4 steel blade that has been sharpened to 10 degrees per side - convex grind - my EDC. I'm using this strop to 'touch up' the edge. I demonstrate the edge both for slice cutting and push cutting performance.

The Kangaroo leather (and nanocloth) are available at Chefknivestogo.com . The 0.1 CBN emulsion formulation is available directly from me. Contact me at ksskss@earthlink.net

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Ken

Re: 160,000 grit Knife Edge!- CBN emulsion on kangaroo

Thu Feb 14, 2013 6:04 am

Ken, any idea when Mark will have the kangaroo strops back in stock? He's been out for quite a while now.

Re: 160,000 grit Knife Edge!- CBN emulsion on kangaroo

Thu Feb 14, 2013 6:47 am

Sent them out today to Mark. Should be in in 2-3 days. Check the box to get email when they come in. Both 3x8 and 1x6. Hmmm 2x6 is out of stock. Well if you need that size let me know. I got them. I'll mention it to Mark. Sent several other things out with it too :)

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Ken

Re: 160,000 grit Knife Edge!- CBN emulsion on kangaroo

Thu Feb 14, 2013 11:09 am

Ken, it's great, all of these high-quality stropping compounds you and Keith are putting on the market. However, the amount of options regarding compound and micron sizes dazzels me.

How should I select a compound for a particular purpose without trying them all? The only guideline I have is that the compound should be finer than the last stone. But how much finer? And what's the practical difference between mono crystlline diamond, poly cristalline diamond, CBN and BN?

There's a few situations in which I strop regularly:
- a straight razor (stainless, it seems) after 10K Choseras
- kitchen knives (both carbon and fairly soft stainless) after a 15K Shapton
- the odd knife (usually a pocket knife or a carbon kitchen knife) I have fed to a 30K Shapton and I want to get even sharper for "showing off purposes" (cutting paper, HHT, shave my face)

Which compounds or even succession of compounds would you suggest for these situations? I usually strop on bovine leather (>= 1 mu), balsa (0.5 - 1 mu) or roo/nano cloth (< 0.5 mu).

Re: 160,000 grit Knife Edge!- CBN emulsion on kangaroo

Thu Feb 14, 2013 10:48 pm

ken123 wrote:Sent them out today to Mark. Should be in in 2-3 days. Check the box to get email when they come in. Both 3x8 and 1x6. Hmmm 2x6 is out of stock. Well if you need that size let me know. I got them. I'll mention it to Mark. Sent several other things out with it too :)

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Ken


Story of my life. I want an 11 inch. :( I have a 2x6 for the EP already.

Re: 160,000 grit Knife Edge!- CBN emulsion on kangaroo

Fri Feb 15, 2013 2:47 am

Mmm .. Mark (@CKTG) is out of that too. Well just send me a PM if you can't wait until the next reorder I get from Mark. I got them in stock now in 3x11 - both nano and 'roo.

Mark (Mark76), this is an excellent and large topic. I'll send you a PM about it before I post a detailed response here.

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Ken

Re: 160,000 grit Knife Edge!- CBN emulsion on kangaroo

Fri Feb 15, 2013 10:23 pm

I was asked this question on another forum:

"How does this compare to the cbn .10 slurry spray.
Also is the nano cloth a good choice for this? "

and I thought I'd post my response to it here as it is a useful piece of information:

This is a NEW formulation. It is an Emulsion. Previously - and still - I have 0.1 micron CBN in a slurry, a paste and - in coarser grits - a clear water soluble suspension.

So the spray is simple, CBN particles in a deionized water based formula. The most generally used formulation available up to 4 microns. The smaller the particles, the quicker they settle out. These are in a spray top bottle.

The clear suspension permanently suspends the particles in the liquid. I've had some bottles sitting on the shelf for over a year and they don't ever seem to settle out. For particles 2 microns and smaller, they stay suspended long enough to not need this suspension. Drying time on the clear suspension takes a bit longer when put on a strop (any kind), but when added to a stone slurry suspension drying time is not relevant. Perfect for waterstones. Comes with a 'Ketchup' top to dispense in droplets.

The paste formulations are not water soluble, but oil based and best used on leather belts. A permanent suspension as well. DO NOT use these on waterstones. Comes with a 'Ketchup' top to dispense in droplets.

Now the Emulsion. This is the first of my emulsion series. I will be expanding it to include poly diamond, with the next one being shipped to me in 0.025 poly emulsion formulation.

I will also be adding other sizes of CBN and Poly as well as possibly some other compounds that are still in development. I'm so impressed with this formulation!

Why am I impressed with the emulsion? This formulation is the result of a LOT of experiments during this last year to develop exactly what I want. Well, it's water soluble. It's a permanent suspension. IT absorbs quickly. It spreads much more easily than paste formulations out there, including my own paste formulations, yielding a much more uniform application. And it GRIPS the leather very strongly, making it perfect for powered applications like leather belts, buffers, etc. It's ability to be applied easily really sets it apart from anything else I've seen, including my own pastes and the multiple formulations I've tested in developing this product. It also lays down a denser coating that a spray formulation.

I also tried it on nanocloth. Very interesting result compared to kangaroo. It absorbs quickly into the nanocloth. Wicking is a term I'll use, like water drawn up by a candle wick. So it doesn't spread as far. You use more to cover the same amount of surface area. Maybe double or triple the amount. Still one bottle will last a very long time. The benefit of this heavier coating is straightforward - more particles to abrade. So you get a faster cutting action, but the same finish level. You don't get the leather draw that you get with 'roo, which I feel provides a burnishing effect too. But you do get a draw effect from the compound itself, due to the heavy coating of particles - a pure 'particle draw' effect, with possibly some draw from the emulsion itself.

I'm anxiously awaiting my shipment of 0.025 poly to see how it works with both 'roo and nanocloth.


All of these formulations have the same amount or concentration of CBN. They have all been tested for particle agglomeration or clumping of particles that you see in lower quality products on the market. No agglomeration!



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Ken
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