Diamond paste

[aikon2020]

So I tried Poltava diamond paste, extra high concentration 1 micron (15k grit) från Ukraine. It seem to work on the edge, it gets sharper, and do it's job, but it doesn't make the paste/strop go black as other diamond compounds I tried, I though it goes black because the steel from the knife grinded off and stuck to the strop. I have mixed it well and as I said, it seem to work for the edge. But when I tried to polish the side of the blade just to try, it seemed to do nothing. I have used THK 1 micron from ebay before, but maybe it's much coarser and that's the reason it seemed to get black faster? I stopped using THK because the quality was not very god, 90% of the small can didn't seem to have any diamond in it at all. Is it that it just takes a lot longer for finer compund to turn black? I use leather strops and not the suede side (I prefer the shiny side)

Anyone having any idea why that might be?

 

[Mr.Wizard]

Is this paste waxy stuff that sits on top of the leather? You may want to try using a hair dryer to melt the carrier into the leather which I hypothesize will leave the diamond grain more exposed. I think 1 micron diamond should still take off enough metal to color the strop, even if not quickly.

It is certainly possible you've been using a "1 micron" compound that has coarser particles.

 

[aikon2020]

Is this paste waxy stuff that sits on top of the leather? You may want to try using a hair dryer to melt the carrier into the leather which I hypothesize will leave the diamond grain more exposed. I think 1 micron diamond should still take off enough metal to color the strop, even if not quickly.

It is certainly possible you've been using a "1 micron" compound that has coarser particles.

This is funny, because I JUST thought about "maybe I need to heat the "waxy" stuff so that it sinks in to the leather and the diamonds can "grip" in to the leather instead of maybe riding and rolling around on top of it"

I just had the though literally like aa minute ago!
But it feels great that other more experienced people had the same thought! I will try it!

 

[aikon2020]

That absolutely made a difference!

 

[Mr.Wizard]

Great! Not every paste behaves the same way. Some will not melt but instead need to be thinned. They make specific diamond-thinning "extender fluid" but you should be able to use water, rubbing alcohol, or light mineral oil depending on solubility, which should be specified with the product i.e. oil, water, or universal.

 

[aikon2020]

Great! Not every paste behaves the same way. Some will not melt but instead need to be thinned. They make specific diamond-thinning liquids but you should be able to use water, rubbing alcohol, or light mineral oil depending on solubility, which should be specified with the product i.e. oil, water, or universal.

I might try a little bit and cut it with some white spirit/mineral spirit, which I have had good luck with previously with other wax/oil based compounds!

 

[kayman67]

The struggle of adapting various products. As mentioned, both with diamond and cbn, they use something that requires heating after being applied. Other methods might work as well, depending on the surface. It's not possible to make such products to work best on anything. Experiment until you get close to what you want. Custom paste is a rare thing.

 

[aikon2020]

One interesting thing I found with this compound is that it seem to leave a bity edge, almost as if it leaves a micro burr, very sharp but very bity, not as smooth of an edge as previous compunds I have tried. I have no idea why this is, anyone have any idea

 

[aikon2020]

And also, I was thinking about testing to add more diamond powder to the compound, maybe it isn't enough? Poltava extra high concentration has 20 carat (4 grams) per 40 gram package. Is it enough or should I try to add more diamond powder of the same micron size?

 

[aporigine]

And also, I was thinking about testing to add more diamond powder to the compound, maybe it isn't enough? Poltava extra high concentration has 20 carat (4 grams) per 40 gram package. Is it enough or should I try to add more diamond powder of the same micron size?

Difficult to answer. I read somewhere that in hydrocarbon, diamond tends to clump. Since diamond is naturally hydrophobic and hydrocarbon is a good match on basis of its very low polarity, the only mechanism by which this counterintuitive clumping occurs (in my largely ignorant opinion) is by electrostatic effects.*

How important this is on a preparation that goes onto a strop (and thus likely shears and distributes any abrasive clumps) I cannot say.

I’d push the diamond concentration (weight in volume) to 20% and see how it performs.

*which makes me wonder if a smidge of tetraalkylammonium salt (a charge carrier soluble in alkanes) might electrically discharge the grains …

 

[aikon2020]

Difficult to answer. I read somewhere that in hydrocarbon, diamond tends to clump. Since diamond is naturally hydrophobic and hydrocarbon is a good match on basis of its very low polarity, the only mechanism by which this counterintuitive clumping occurs (in my largely ignorant opinion) is by electrostatic effects.*

How important this is on a preparation that goes onto a strop (and thus likely shears and distributes any abrasive clumps) I cannot say.

I’d push the diamond concentration (weight in volume) to 20% and see how it performs.

*which makes me wonder if a smidge of tetraalkylammonium salt (a charge carrier soluble in alkanes) might electrically discharge the grains …

I will try to add another 20 carat (4 grams) to see if it cuts better. If it works I might do that to the other cans as well.

I also thought that maybe mixing a bit with som mineral spirit/white spirit to make it more loose and maybe making it easier to sink in to the leather. Good idea?


I ordered some paste and diamond powder from ebay, I will try to experiment with the concentration.

 

[aporigine]

I will try to add another 20 carat (4 grams) to see if it cuts better. If it works I might do that to the other cans as well.

I also thought that maybe mixing a bit with som mineral spirit/white spirit to make it more loose and maybe making it easier to sink in to the leather. Good idea?


I ordered some paste and diamond powder from ebay, I will try to experiment with the concentration.

If you can replicate something soft but not fluid, like petrolatum or even lip balm, that might be a sweet spot.

If I try some diy, I have lip balm base (beeswax plus mineral oil) and empty tubes. That might be a super convenient format — solid enough to stay homogeneous, but soft enough to condition the strop without heat.

Dang I should patent it. But I’m gonna open-source this idea. Anyone who plays with it, share your observations with me please.

 

[aikon2020]

If you can replicate something soft but not fluid, like petrolatum or even lip balm, that might be a sweet spot.

If I try some diy, I have lip balm base (beeswax plus mineral oil) and empty tubes. That might be a super convenient format — solid enough to stay homogeneous, but soft enough to condition the strop without heat.

Dang I should patent it. But I’m gonna open-source this idea. Anyone who plays with it, share your observations with me please.

Well, the problem is that it is already in an oil based paste. So my ideas right now is to make it work, maybe not making my own paste from the ground up! Sorry! And thanks for the input.

 

[aikon2020]

Difficult to answer. I read somewhere that in hydrocarbon, diamond tends to clump. Since diamond is naturally hydrophobic and hydrocarbon is a good match on basis of its very low polarity, the only mechanism by which this counterintuitive clumping occurs (in my largely ignorant opinion) is by electrostatic effects.*

How important this is on a preparation that goes onto a strop (and thus likely shears and distributes any abrasive clumps) I cannot say.

I’d push the diamond concentration (weight in volume) to 20% and see how it performs.

*which makes me wonder if a smidge of tetraalkylammonium salt (a charge carrier soluble in alkanes) might electrically discharge the grains …

Another observation is that I have seen others use 10 carat per 40grams on other forums and succeded to use it to polish edges and the strops became black from the metal. I think that guy was using balsa. Maybe I should try to use abother type of strop? Like suede leather maybe, ut should be closer to the grain of the wood with the furriness of the suede maybe.

 

[aikon2020]

Well, I tried the suede on another strop I have with no different result. So what I don't understand is why the strop don't turn black, it gets slightly darker and after several knives the small amount of paste seem to clump up and look like eraser "dust" or whatever you call it, the mini "sausages" you get after erasing pencil writing (sorry English isn't my first language). My hypothesis is that the paste gets saturated with steel dust even if it don't turn black, only a bit darker. It seem to cut really well though, and fast and it leaves a bite to the edge. I ordered several cans and they all behave the same.

Previously I have only used THK paste from ebay, it cuts MUCH slower and leaves a moore smooth edge, or smoother apex.

Maybe the diamonds in this new Ukrainian paste cuts much better and more aggressively, more like ultra fine sharpening rather than only polishing

Since it actually seem to cut extremely fast, just a couple of drags on each side, maybe it is not the dismond concentration, maybe it just behaves differently?


Anyone have any thoughts on this?

 

[aporigine]

Well, I tried the suede on another strop I have with no different result. So what I don't understand is why the strop don't turn black, it gets slightly darker and after several knives the small amount of paste seem to clump up and look like eraser "dust" or whatever you call it, the mini "sausages" you get after erasing pencil writing (sorry English isn't my first language). My hypothesis is that the paste gets saturated with steel dust even if it don't turn black, only a bit darker. It seem to cut really well though, and fast and it leaves a bite to the edge. I ordered several cans and they all behave the same.

Previously I have only used THK paste from ebay, it cuts MUCH slower and leaves a moore smooth edge, or smoother apex.

Maybe the diamonds in this new Ukrainian paste cuts much better and more aggressively, more like ultra fine sharpening rather than only polishing


Anyone have any thoughts on this?

Those sausages are bad news. I’d definitely hit the strop with a bit of mineral spirit, preferably higher-boiling so it lasts through a use session.

 

[aikon2020]

Those sausages are bad news. I’d definitely hit the strop with a bit of mineral spirit, preferably higher-boiling so it lasts through a use session.

Please explain!
It only becomes."sausages" when I use alot of paste and only after a while.
If I use very little paste, it wont develop those "sausages"

 

[aikon2020]

Those sausages are bad news. I’d definitely hit the strop with a bit of mineral spirit, preferably higher-boiling so it lasts through a use session.

Do you think it's better to use spirits on the strop after applying the paste? Maybe dab it on, or before applying the paste or just mix spirits with the paste and store it in an air tight container so it wont evaporate during storage?

 

[aikon2020]

And also, I am considering just leaving it and accepting it. It DOES work, just not in the way I am used to.

 

[aporigine]

Please explain!
It only becomes."sausages" when I use alot of paste and only after a while.
If I use very little paste, it wont develop those "sausages"

so use just a bit of paste! The working amount should spread out micron-thin.

The sausages introduce macroscopic roughness to your strop. The edge will go bumpity bump like a Porsche on a bad road. Cannot be good for consistent results on the apex.

 

[aporigine]

Do you think it's better to use spirits on the strop after applying the paste? Maybe dab it on, or before applying the paste or just mix spirits with the paste and store it in an air tight container so it wont evaporate during storage?

After.
A few drops*; massage it in with a fingertip.

*or however much is needed for that perfect state between dry (uneven distribution) and wet (abrasive might be squeegeed by the blade.)

 

[aikon2020]

After.
A few drops*; massage it in with a fingertip.

*or however much is needed for that perfect state between dry (uneven distribution) and wet (abrasive might be squeegeed by the blade.)

You dont think that the finger will remove the diamonds?

 

[aporigine]

You dont think that the finger will remove the diamonds?

Too few to matter.

To add some quality handwaving:
assuming even area distribution, your loss will be (area fingertip)/(area strop + area fingertip) which ought to be in the range of 1% or even less.

 

[aikon2020]

Maybe I am just an idiot and should leave it be and use it, since it is working. Even if the strop don't turn black, it is actually going darker after use AND the strop does start smelling like metal.

I just looked and Poltava diamond tools claim that their 1 micron paste is 15k grit.

The ebay stuff if you look at diamond powder that is made in china claim that "1 micron" is 5k grit.

So maybe Im just lot used to the dismonds being that small and removing material slower than the bigger diamonds.

I feel like an idiot that OCD's over stuff line this, especially when it actually works well.

 

[aikon2020]

Difficult to answer. I read somewhere that in hydrocarbon, diamond tends to clump. Since diamond is naturally hydrophobic and hydrocarbon is a good match on basis of its very low polarity, the only mechanism by which this counterintuitive clumping occurs (in my largely ignorant opinion) is by electrostatic effects.*

How important this is on a preparation that goes onto a strop (and thus likely shears and distributes any abrasive clumps) I cannot say.

I’d push the diamond concentration (weight in volume) to 20% and see how it performs.

*which makes me wonder if a smidge of tetraalkylammonium salt (a charge carrier soluble in alkanes) might electrically discharge the grains …

If I were to add more diamonds, .I was thinking that I would weigh them, add a couple of drops of white spirit for them to dispers in and then add it to the paste

 

[aporigine]

… I feel like an idiot that OCD's over stuff line this, especially when it actually works well.

You are in good and plentiful company.

 

[M1k3]

As for the strop not turning black, I have 2 strops, one loaded with 3 micron, the other with 1 micron. Both are CKTG branded. The 3 micron one started to turn black after the first use. After a month it pretty much completely turned black. The 1 micron has some black on it, but not much and it's been like 2 years since I started using that one.

 

[aikon2020]

As for the strop not turning black, I have 2 strops, one loaded with 3 micron, the other with 1 micron. Both are CKTG branded. The 3 micron one started to turn black after the first use. After a month it pretty much completely turned black. The 1 micron has some black on it, but not much and it's been like 2 years since I started using that one.

Thank you, then I am not imagining things at least! Puh

 

[aikon2020]

I think I will just use it and trying to stop OCD over things

 

[aporigine]

I think I will just use it and trying to stop OCD over things

To butcher the DeBeers slogan:
OCD over diamonds is forever.