Diamond spray/paste medium

[crazywednesday]

My first post here! I have been buying from cktg for a long time and just today I noticed a forum.

I have seen a few videos of diy diamond spray. Seems like most use rubbing alcohol and/or water. What other mediums would be good for suspension? What are they using in the gels and pastes? Any suggestions would be great. I plan to use these on leather strops.

Cheers,

Justin

[XexoX]

My first post here! I have been buying from cktg for a long time and just today I noticed a forum.

I have seen a few videos of diy diamond spray. Seems like most use rubbing alcohol and/or water. What other mediums would be good for suspension? What are they using in the gels and pastes? Any suggestions would be great. I plan to use these on leather strops.

Cheers,

Justin

Welcome Mr. Justin! Great to have you here.

[Radar53]

Hi Justin and welcome to the forum.

There is plenty on this subject in the "Sharpening" thread here viewforum.php?f=4 as it applies to freehand sharpening as well. There is a current post there already being discussed. Search & hunt for other stropping threads there as well, because it's a subject that gets discussed regularly.

[taz575]

I think it would be hard to make your own suspensions. I bought some diamond powders for finishing blade surfaces (not edges), but haven't used them yet. They are crazy expensive! I got some in the 400-500 range and 800-1000 grit IIRC? I was using SiC powders to help with hand sanding knife blades and wanted to try the diamonds on more wear resistant steels.

The liquid needs to be able to suspend the particles, dry quickly and not mess up the strop itself. If the particles are super light, they may float on top of the liquid and not get picked up when spritzing a strop, or may sink to the bottom and spray a big glob of the particles. Also, the grading of the particles can be an issue with how tightly they control that! The alcohol helps dry the spray quicker, but it's a balance of alcohol and water or oil and how they mix and interact with the particles.

It's easier and less headaches to go with a store bought spray/emulsion.

[Kekoa]

I didn't even know you could try to make your own. Interesting thought, but I would think taz is right on this one.

[aporigine]

I don’t remember where I read it, but various fluids were tested to use a way to sort diamond powders into various grit classes by settlement speed — with coarser grits settling out sooner.

Agglomeration of the diamond particles was a colossal pain, with the solvents I thought would be winners (hydrocarbons) turning in poor results. Iirc diamonds are real good at holding onto electrostatic charges, which in dielectric nonpolar solvents messes up the separation.

I’m a retired chemist, and I don’t have a handle on how to make stable, monodisperse (narrow particle size range) diamond suspensions.

Though I do have a hankering to buy some 100-grit diamond and a bit of mildly detergent gun grease and see how that works on a big thinning job …

[taz575]

I moved the topic to the Sharpening Forum to hopefully get more traffic to it!

Gun grease and diamond compounds will work to lap a surface, but you need something backing it to really remove metal. With being diamond, it may be hard to get something to lap it against since the diamond may wear it as well? I use SIC powders, mineral oil or rapid tap cutting fluid and SiC sandpaper on foam or popsicle stick backers to use as "fingerstones" for a kasumi finish and it's a neat way to do it. I picked up some diamond powders to try out using the same technique, but haven't used them yet!

You may be better off using cheap, coarse diamond plates than the grit itself?

[crazywednesday]

Interesting stuff here. I appreciate everyone's input. The Ken Schwartz cBN emulsion smells and has the consistency of rubbing alcohol. I will probably start with that.

If its an oil based medium, would the lubricity reduce the effectiveness of the diamonds on the leather?

Justin

[taz575]

The oil is the carrier and would make the leather oily, but shouldn't effect the diamonds? The pastes I have used are waxy and soak into the leather and dry, but leave the leather a bit waxy. I can scrape the leather with the spine of a knife and pull a lot of wax/residue off. Not sure if the oil would "treat" the leather and change the draw of the leather itself? I also don't know what concentration to do with the diamonds, either to get a nice coating?

[Diemaker]

I use demineralized water to make my stropping compounds. None of the diamonds float, they all sink so you need to shake the bottle before dispersing. You want 1 gram of abrasive per oz of water at the most, remember less is more when stropping. I have made my own from 40 microns to .1 and have seen no issues with the diamonds clumping. The only problems I have had are with the spray pumps dying quickly so I am still figuring out what to use to dispense them.

I want my strops to have the least amount of friction when I run them across my knives to reduce convexing and edge damage for harder blades so stay away from oils or waxes. I started out using Saddle Soap for the carrier, since it is good for leather, but between hearing someone say they get sharper edges with water-based carriers and seeing damage to a Maxamet edge I then switched to water years ago. The only problem I have had with water is it makes the leather shrink causing the edges to curl up.