# Economical diamond lapidary paste as alternative to .1 micron CBN?



## phonecall (Apr 13, 2016)

Hi all.

I've had decent results playing around with some Richmond .5 micron diamond paste. It's a definite upgrade from green stropping compound. 

I'd like to take it down to .1 or .125 just to see what results I'd get. Richmond's paste doesn't go down that small. 

Not trying to open a can of worms, but I'm not keen on paying $50 just to try a .1 micron strop. I'm not sure my edges are to the point they'd even benefit. 

But I see that Amazon has .1 micron diamond lapidary paste for $12 or so. http://www.amazon.com/dp/B00I5B1JY2/?tag=skimlinks_replacement-20

Wondering if anyone has ever tried it. Does it hold a candle to .1 micron CBN from Ken? Or should I give it a miss and bite the bullet and get the good stuff?

Thanks


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## Nife (Apr 14, 2016)

It is not easy to get objective information about Diamond pastes and CBN. CKTG is generally pro stropping compounds. I believe that bladeforums is somewhat neutral, and might be a good site for information. The Amazon reviewers typically do not know much about knife sharpening, and the cheap diamond compounds sold online have a low concentration of diamonds; that is why they are cheap. Typically for Japanese knives, the top free hand sharpeners do not like to use ultra fine compounds. Some connoisseurs of straight edge razors use very fine particle diamond compounds, but (I am an avid fan of the electric razor).


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## Steampunk (Apr 14, 2016)

Sadly, you invoked one of this forum's evil spirits, otherwise this could have been an interesting topic.

I'll be the unpopular one, however, and say that in the hypothetical situation that I _was_ stropping to 1/10th of a micron for some reason and only had those two choices, I would go for the CBN. There are five different main factors that separate the compounds used in stropping: 

1. Abrasive concentration
2. Abrasive scale consistency 
3. Abrasive hardness
4. Abrasive shape
5. Carrier type (Water vs. oil, suspension vs. emulsion, etc.)

All effect the sharpening process. Ken's getting his gear from a known industrial supplier, possibly to his own specs for grit concentration and maybe consistency, and rebranding them/marking them up for retail sale. The compounds are decent quality, if expensive for what they are. If you do some research, you will find several industrial suppliers in the US making precision lapidary and polishing abrasives, and if you have the gumption you can buy compounds of similar quality to Ken's from them direct over the phone. It just depends upon who you want to give your money to, and if you want to learn more about abrasives and the companies that make them on your own. 

According to the straight razor sharpeners who have dabbled in the dark arts, CBN particles tend to result in a slightly smoother edge at the .1-.125 micron level than polycrystaline or monocrystaline diamond, and CBN is also more suitable for power stropping with a belt grinder or buffing wheels. This is good for shaving, maybe chisels or carving tools (Never stropped one of mine that high), and imaginably is acceptable for certain types of kitchen or pocket knives for parlor tricks (Although diamond tends to retain its toothiness to higher grits.). However, for most food prep, this level of refinement isn't necessarily ideal (Especially if your bevel isn't perfect to start with.). 

The suitability of compounds this fine depends upon your application, and how much you just want to experiment for the sake of it. I had a phase with strops, trying to see how far I can go. You can genuinely feel a noticeable increase in perceived 'sharpness' with each finer step, which feels cool for the first few cuts, but the problem comes when you use the knife for any period of time. Because the edge is so refined, there is no residual 'toothiness' to help keep the blade cutting into the food once corrosion or wear starts taking place, so it stops biting into the food very quickly. You can actually see this with a paper towel test... Roll up a paper towel, and try cutting into it. That highly refined stropped edge will only cut a short distance into the roll. A coarser edge - providing it is deburred - however, will saw deeper into the roll, and possibly all the way through. Throw some use into the equation, and that stropped edge will stop cutting into the paper towel long before the lower grit one. That coarser edge might not pass a shave test as well as a highly stropped edge, but will perform better on most types of food past the first few cuts, barring woody vegetables like carrots. 

The really nice thing about pasted strops, though, is how easy they make it to obtain a 'clean' edge, free of burr. This is great when you first start sharpening, and sometimes even after if you're in a hurry. However, as weird as this sounds, you might actually find it more beneficial - rather than go finer than 0.5 micron - to actually go coarser than 0.5 micron if your application is food related, and try a diamond or CBN paste between 1-3 microns. You'll still get the clean edge easily, but will find more toothiness, and since the coarser grits will cut faster (Providing the concentration is decent) you'll actually be able to use it for touch-ups when the edge starts to wear rather than having to hit your stones again... You won't get as much of that initial light-saber feeling, but in the long-run you might grow into this toothier type of edge. Most people do. 

However, if you just want to play, have a bash at 0.1 micron... The only reason why the cheaper diamond paste might be inferior to Ken's CBN is (A) - cutting speed, and (B) - grit consistency (Which means that the edge will never be a uniform 0.1 micron finish; there will be deeper, random scratches. Maybe not terrible for a kitchen knife, but unacceptable for a razor.). Because of this, the cheaper paste might not feel as fine or effective as the higher quality product, but whether or not this matters is up to you. If you want to truly experience 0.1 micron, I would also buy some 0.25 micron to fill the gap between this and your 0.5; fine strops are not fast cutters (Particularly at low abrasive concentrations), and need a tighter progression to fully erase the scratch pattern from the previous grit.

If the cheaper compound is oil based, it might also not be as easy to clean off the blade as a water-based compound. This isn't important for woodworking tools or pocket knives, but is important on kitchen knives or razors which are in contact with your food or skin.

Hopefully this helps...

- Steampunk


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## phonecall (Apr 14, 2016)

Very informative post, Steampunk. You nailed two things that apply to me. 

Firstly, the parlor trick aspect of a very refined edge- which if I'm being honest is what I'm searching for and at some level I knew it's not practical (though your post about the paper roll really drives that home). 

Secondly, how easy the strop is for me to use. I'm no expert and need to refine my freehand technique, and I suspect I'm not getting all the performance out of my waterstones due to my less than perfect freehand skills. My guess is the forgiving nature of the substrate (balsa in this case) compensates for my inability to hold a perfect angle on the stones, and that's why the edges really improve after stropping. (Not sure if anyone else has experienced this.)

In my defense regarding opening a can of worms -- I didnt really know about the different leanings of the various forums. I did know CKTG was pretty pro-Ken, so I wouldnt have asked there for a dissenting view.

I searched here, and saw Dave Martell mentioned a few years back buying CDN direct from the wholesaler at lower prices (they dont appear to sell direct anymore), so I thought this might be a good place to inquire about alternatives.

Searching around last night, I found some CBN .1 micron in a smaller quantity but at a lower price. (Not sure if its cool to post the link.) After reading STeampunk's post, I need to think again if i want to chase a .1 micrno edge. If i do, I'll buy that small quantity of .1 micron CBN rather than roll the dice on some paste of unknown quality and uniformity.

Thanks. Really didnt mean to open a can of worms. I was just trying to save a few bucks.


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## ThEoRy (Apr 14, 2016)

To be honest, I don't think you need to go any smaller than .25 micron. Lately I'm stropping at 1 micron however because I love the bite. Is there a difference? Marginally.


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## dough (Apr 14, 2016)

phonecall said:


> I searched here, and saw Dave Martell mentioned a few years back buying CDN direct from the wholesaler at lower prices (they dont appear to sell direct anymore), so I thought this might be a good place to inquire about alternatives.



When I read your post I thought back to that whole buying direct thing only to find it basically doesn't exist anymore. A site called us products was used by some members and still seems to offer decent prices but doesn't go below .25 microns atleast that I noticed. 
mostly useless two cents as you seem to be headed in the right direction goodluck and have fun. oh I'm also rather sure your good to post links or mention websites as long as you aren't soliciting for that business. heck the next member that comes along with a similar question might find it helpful.


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## phonecall (Apr 14, 2016)

dough said:


> When I read your post I thought back to that whole buying direct thing only to find it basically doesn't exist anymore. A site called us products was used by some members and still seems to offer decent prices but doesn't go below .25 microns atleast that I noticed.
> mostly useless two cents as you seem to be headed in the right direction goodluck and have fun. oh I'm also rather sure your good to post links or mention websites as long as you aren't soliciting for that business. heck the next member that comes along with a similar question might find it helpful.



http://www.oldawan.com/sharpen/shar...sories/kme-cubic-boron-nitride-cbn-emulsions/ It comes out to about $24 shipped for 7 grams. I just did the math, and 7 grams is only .25 ounces. Not a great per ounce price.


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## chinacats (Apr 14, 2016)

I've bought from USProducts, they are legit and inexpensive...


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## Steampunk (Apr 14, 2016)

phonecall said:


> Firstly, the parlor trick aspect of a very refined edge- which if I'm being honest is what I'm searching for and at some level I knew it's not practical (though your post about the paper roll really drives that home).
> 
> Secondly, how easy the strop is for me to use. I'm no expert and need to refine my freehand technique, and I suspect I'm not getting all the performance out of my waterstones due to my less than perfect freehand skills. My guess is the forgiving nature of the substrate (balsa in this case) compensates for my inability to hold a perfect angle on the stones, and that's why the edges really improve after stropping. (Not sure if anyone else has experienced this.)



Parlor tricks are fun sometimes ... In this case, however, I think that the notable edge improvement you are experience is possibly more due to the _existence_ of the pasted strop in your sharpening progression than necessarily the _fineness_ of it. 

Balsa also isn't the finest stropping substrate (I mostly use balsa with compounds 1-micron and over.), so you might even notice a difference just by stropping with your 1/2-micron compound on a piece of leather following your balsa strop. If you're jumping to 0.5 micron from a 6-8K stone (Which would typically be around 2-3 microns), you might want to also consider adding a 1-micron compound into your progression to fill the gap and fully convert the scratch pattern. An edge's quality comes from what precedes your finisher (Stone or strop) more than the finisher itself. 

Hopefully this helps...

- Steampunk


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## Nife (Apr 15, 2016)

An outstanding, mature, unbiased, and informative post. Perhaps you should post this on the KS sponsored sites to help educate some people about the stropping products, and possible alternative sources of the products. In my opinion, the diamond compounds and CBN can be used to maintain edges, but there are other options for kitchen knives that do not involve the hassle, expense, and necessity of using expensive novelty strops (Kangaroo and Nano Cloth). Perhaps fortunately, I don't have the funds to buy those products. 

I am a food guy. I don't understand why some people want the perfect close shave using atomic sized particles on strops to get the razor sharper than a scalpel. The whiskers will start to grow back within a couple of hours. Electric razors are relatively cheap to use and do a reasonable job. Modern razors do a reasonable job of shaving, but the blades are expensive. Carter allegedly just uses Kings and paper stropping to hone his razors. KS has a gold mine from the "Shavers" seeking the holy grail, but they are purchasing fools gold. In gathering information about sharpening and maintaining kitchen knives, I am biased, and I am more trusting of the JKI and JNS approaches. That is not to say that some of the compounds don't have some value and use for some people, but in my opinion, they are over priced, and little objective information about their effectiveness on Japanese knives is available. Nano cloth strops, oh boy, and I know of only one person who sells them. Stropping corrects some errors in sharpening on stones which is probably why some people love them. I am not a good sharpener, but I am hoping to get better on stones, and avoid the strops with compounds.


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## Nife (Apr 15, 2016)

phonecall, I am pretty sure that KS sells the compounds to KME and KME sellers, WE, and WE sellers which might explain why the price is not so good.


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