Diamond pastes stropping explanation/advice

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Motega

Motega

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I am posting this info because it took me a while to get here when I was first learning the very basics (still am), this was from a particular seller that doesn't sponsor (I don't think he does, but it's definitely possible and I am too lazy to look right now).

But I have removed references to the seller only keeping the facts. Hopefully this will help someone else move forward a little faster... bold emphasis was added by me.

The main abrasive component of diamond paste is diamond powder. Depending on the grain size of the diamond powder, the abrasive properties of the diamond paste are manifested.
We produce pastes with grain sizes from 0.25 microns to 63.0 microns. In some cases, by order of consumers, we made a paste with a grain size of 125.0 and even 200.0 microns.
When sorting diamond powder, it is impossible to separate the grains with an accuracy of one size (cells of special sieves do not allow), therefore, according to Ukrainian standards, the upper and lower grain values are written. For example, paste 5/3 has a powder with an average size of 4 microns.
The higher the grain size, the rougher the paste. For example, 60/40 pastes are used for rough grinding. Conversely, 0.25 paste is necessary for superfinishing polishing.
The next important parameter of diamond paste is concentration, that is, the amount of diamond powder per 1 kg of diamond paste. We make a paste of three types of concentrations: normal, increased and high. The higher the concentration of the paste, the faster you can achieve the desired result. (note: not sure why you would want medium concentrations... I get high and low...)

The choice of paste always depends on the preferences and experience of the customer. Our increased concentration paste works well with all types of steels. My opinion is that you can start with 5/3 paste for high-quality knife sharpening. In rare cases, very blunt knives (but I don’t think you have one) with paste 14/10. And further move towards a decrease in graininess. And of course, if you want to achieve very fine polishing without a 0.25 paste, you definitely can not do it. (a bit of subjectivity here, but I think he means mirror finishes)
That is, based on my sales experience for knife sharpeners, the standard set looks like this: (here is the progression I have been using with good results) increased concentration of 5/3, 3/2 (or 2/1), 0.25/0.


miror polish knife edge.jpg
 
Motega said:
I am posting this info because it took me a while to get here when I was first learning the very basics (still am),
Click to expand...

Without learning, then polishing an edge is merely repetively rubbing of rocks on metal. I hope that day never comes for me. Your edge looks beautiful. Why not tell us the manufacturer? I just read the forum rules, and there's nothing that says you can't share. After all, if it helps someone advance their skill a little quicker...

For my "pretty" work, I like Ken Schwartz' CBN emulsion on his nanocloth. His stuff is a little more expensive, but there's the benefit of getting the guidance in choosing the best tools for whatever you're trying to achieve.

I also use Venev diamond paste on kangaroo. The finish provided by a particular grit is finer than I would expect when viewing under magnification, when compared to similar grit stones. Frankly, I don't know if this is the way things are supposed to be and my expectations are off. Regardless, a little experimentation has taught me where this product is useful, so it's part of my kit.

The product that left me unsatisfied is Kent Supplies. They're inexpensive, so I bought a selection. The effect of their products is less than I'm accustomed to.

Here's an edge I did last week. It's an old beater from my sister-in-law's kitchen that I finished with 0.25μ CBN. I'll probably not put a pretty edge on this one again, but I felt like doing it this time around.

[Hmmm... weird... can't figure out how to post a picture. Oh well...]
 
The diamond paste is from Ukraine.
The blade is a Zero Tolerance in 20CV.
I have Wade and Yaxel to thank for getting me this far.
I use a TSPROF and variety of stones, finished with a 10k Suehiro and then the progression of diamond paste mentioned.
 
R RustyIron If you want to learn more about the diamond paste me a Motega use email me at wadenorton2008@yahoo.ca

Most diamond paste's from 3 micron and lower are 4 carat weight per 40 grams on most standard paste,the guy I deal with also sell's 10 and 20 carat weight paste as well for 28 to 32 bucks per 40 grams.
Once you start going higher micron numbers then the carat weight goes up to keep the particle ratio somewhat the same.

He has oil and water base paste's but the oil is better because it dry's to the strop better then water base,his oil base use's oilec acid for the oil and is petrol free.
 
Has anyone tried getting scratches out of the blade using diamond polish? You can see some tiny ones behind the edge here.
They look bad because this shot is macro but aren't that bad with naked eye
 
wade7575 said:
R RustyIron
Most diamond paste's from 3 micron and lower are 4 carat weight per 40 grams on most standard paste,the guy I deal with also sell's 10 and 20 carat weight paste as well for 28 to 32 bucks per 40 grams.
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Thanks, Wade.
I put your contact info into my notes. I'll get ahold of you after the new year. I'm playing with some other stones right now, and I only like to introduce one new variable at a time into my process.
 
Motega said:
Has anyone tried getting scratches out of the blade using diamond polish? You can see some tiny ones behind the edge here.
They look bad because this shot is macro but aren't that bad with naked eye
Click to expand...
1. depending on actual roughness and grain size you may get scratches
2. diamond is not recommended for steel, CBN is recommended. although most are not aware of it and reply: we always use diamonds.
 
as the hardest material, diamond will work anywhere
I am talking about "recommendations", based on natural properties of both materials.
the same is true about sharpening stones.

the other thing is that you can not feel/see it at once, unless using wheels.

OK
nobody uses wheels for knife sharpening
:)
 
Diamond is much harder and 1/5 the price of CBN, what's not to like?

I believe the "recommendations" you speak of are for powered grinding, as in 1000 feet per minute or more, which has nothing to do with our hand powered grinding. For argument's sake, if you could keep the diamond crystals cool, they conduct heat about 4 times better than pure copper, then no one would use CBN for nearly anything.
 
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diamond and cbn stones with similar dimensions and concentrations cost nearly the same price
CBN pastes are a bit more expensive, but not 5 times

yes, for powered grinding CBN wheel for steel is a must
 
I am talking about the price of diamond or CBN, not products made from them.
 
for small orders like 20cts CBN powder is just twice more expensive than diamond powder, 16usd vs. 7usd per 20 for bigger manufacturers difference is much smaller and difference is about 20%, simply because synthesis volumes are uncomparable
 
When I am buying kilos of quality diamond powder here in the U.S. the difference is 5 fold, the difference would be much bigger if compared to low quality diamond. In what country is the price difference so close?
 
Mr.Wizard said:
I see that your profile reads "Seller of CBN stones and diamond pastes" -- do you have a website?
Click to expand...

A abrasivetools cannot advertise his business on this site unless or until he has the proper membership level.

Sorry, but the rules apply to all.

This thread is now closed.
 
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