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Diamond Paste Concentration?

I see different concentrations of 0.1u and 0.25u diamond paste available:

  • (H) 50%
  • (M) 25%
  • (L) 10%

Which concentration would be best for a pasted balsa strop?
 
Often, the actual concentration is particle size dependent. There is no real standard here, so it gets confusing.
Finer 'grits' usually have a lower % than the heavier stuff. Reading the charts can be exhausting, esp when you're trying to map out one brand against another.

I 'think' HA uses 10 carats of diamonds in 2 oz of spray. I don't know what the 'percentage' would equate to - it would depend on whether or not your comparing volume or mass I think. Whatever it is - it works well.
I'm wondering what a 50% concentration of .1µm of diamond paste would be like - the last stuff I had was, I think, 10% and it worked fine.
The bigger part of the story, well - for me anyway, is PSD. A lot of the Chinese companies have wildly varying particle size distribution in their powders, which didn't make me happy.
Yeah - sure, that cheap stuff will work, but a material that's more consistent will, obviously, work best.
 
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I have found 0.1 micron paste, all the same grit (200,000), but I am still confused as to which concentration to purchase. I know Slash McCoy had recommended this paste for my balsa strops for maintenance after each shave, but at the time I didn't know that different concentrations were even an issue.
 

David

B&B’s Champion Corn Shucker
Slash recommended you strop on diamond paste after each shave? Makes my face burn just thinking about that
 
Yeah, back in a thread about refreshing a straight:

As many as it takes.

Might be a lot if your edge is really going off. If you hit the pasted strop after every shave you won't see your edge go north like that, at least not as frequently. I use diamond on balsa and I never have to re-hone. YMMV.
 
Which exact product are you looking to purchase? I'll see if I can decipher what you're looking at.
 
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Yuri sells by weight - 50% concentration is 1/2-1/2 carat weight of diamonds vs carat weight of medium/carrier.

10% will be fine. Higher concentrations will, most likely, only reduce your lap count.

His product is for lapidary purposes - doesn't have a very tight PSD.

You'd do better, dollars to carats, to buy the powder and mix your own.
 
Yuri sells by weight - 50% concentration is 1/2-1/2 carat weight of diamonds vs carat weight of medium/carrier.

10% will be fine. Higher concentrations will, most likely, only reduce your lap count.

His product is for lapidary purposes - doesn't have a very tight PSD.

You'd do better, dollars to carats, to buy the powder and mix your own.

Thanks! Your answer really helps a lot.
 

Slash McCoy

I freehand dog rockets
Gamma is right. 10% will give you better distribution. 50% is sure to give either spotty coverage or way too much diamond.
 
Honestly, even 10% is overkill - IMO - 3% is all you really need. Hence the 'mix yer own' concept.

Higher concentrations increase the incidence of the number of larger particles on the strop.
Then tend to 'clump' a bit also, so that's where you get the uneven action from, and that's the last thing you want to introduce here.

That grade diamond in .1µm will have a fair amount (relatively speaking) of particles ranging up to 1µm and possibly larger also. So -a 50% concentration will increase that variable by a significant margin.
It's a numbers game - hitting the sweet spot isn't hard but shooting for it might pay off.

HA used to sell .1µm poly spray, was a very very good mix. I don't recall having a single instance of problematic rogue scratches and that's after going up to 250 laps on a 6" paddle.
 

Slash McCoy

I freehand dog rockets
Sure that works. Or glycerine. Add alcohol or water, whatever, depending on your substrate and what you hope to accomplish.

Me, I just use Ted Pella paste, or Chinese ebay paste. And yeah particle size variation technically is a problem but once you get to sub sub micron grit, even a 2x variation is no big deal, when it comes to honing/stropping razors. If it seems too concentrated, thin it with whatever. I use lighter fluid or methanol or ever clear or even wd40. You aren't eating it. Just rubbing some steel on it. The most important factor besides nominal grit value is the flatness of the substrate. Iow, balsa or paddle. I don't like a hanging strop with abrasive. If you convex the edge as much or more than the natural hanging strop curvature, then the clean hanging strop doesn't have as much to go on. Just my conjecture... Do it like u feel it. This is just what seems to work for me and my razors.
 
Your advice has been very valuable, Slash, and I am using most of what you've said to construct my pasted basla strops:

Quarter inch thick balsa glued to 4x12inch polished marble edge tiles. I will be lapping the balsa with sandpaper glued to another edge tile.

I am also gluing veg tanned leather to the opposite sides of the tile from the pasted balsa, for use until I get a proper leather hanging strop.
 

Slash McCoy

I freehand dog rockets
Slash recommended you strop on diamond paste after each shave? Makes my face burn just thinking about that

Its all about the grit size. About .5u is sort of a sour spot which can give a harsh edge. At .1u or finer it is pretty hard to make a harsh edge. Especially on balsa or some other resilient substrate. Oh, and don't put too much. Thats the other secret. If you think you got enough, you got at least twice the correct amount. You want the diamond embedded in the balsa and not just sitting on top. So use very very very very very sparingly, rub it in good, and use plenty of light laps and bobs yer uncle. Seriously, this works great for me. But don't try it if you just don't feel the vibe. More than one way to gitter done.
 
A good edge can definitely be mucked up beyond repair on .1µm, and even a moderate variation in the PSD can be felt quite easily.
Well - I can tell quite easily. Someone else? Who knows. Some people think a Norton 8k edge is good. So - there's that.

Of course, you'd have to compare the effects of each side/by/side - and if your edge is whacked or subpar or the razor isn't one to take a fine fingerprint well - then you might not notice. It also depends on how well you can finesse the touch when using the paste.

Back when I was digging into the diamond paste stuff, Pella's office wouldn't give up concentration info or PSD data - so I passed over his products just because I don't have the time to deal with that type of buffoonery. It's a freaking abrasive, even the low-end dealers from China will pony up a PSD chart. One has to wonder about the accuracy though.

The Chinese diamond paste off fleapay - the stuff I tried - I wouldn't use it to polish a spittoon.. but that's just my take on things. Way I see it, if I can buy crap or good stuff, I'll buy the good stuff. I"m not the kind of person that tries to fool myself into thinking that the crap is 'just as good' when there's a world of science proving that's not the case. Lot's of things 'work' - but lots of other things work better.

But - if you don't go side-by-side, there's no way to tell the difference.

Best part of using a paddle with diamond paste is it removes the variable of slack, give, stretch, etc.
With diamond - I find those variables to be excruciatingly painful to deal with.
Convex bevels? Who cares? That's why we have bevel setting hones.

Thick mineral oil is fine to use as a medium. You can also get thinners and mediums from lapidary supply hgouses.
What you don't want is clumping - anything you do, just mix it slowly and very well. If it's very fluid, then shake it up a lot before using it.
I tried beeswax - I think a mix of that with mineral oil might do well, on its own its too thick for me.

For a substrate - I found a heavy-nap leather paddle to be beyond excellent, like nubuck but a bit nappier even.
Heavy weave cotton webbing glued to a board was pretty close enough to that though.
 
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Its all about the grit size. About .5u is sort of a sour spot which can give a harsh edge. At .1u or finer it is pretty hard to make a harsh edge. Especially on balsa or some other resilient substrate. Oh, and don't put too much. Thats the other secret. If you think you got enough, you got at least twice the correct amount. You want the diamond embedded in the balsa and not just sitting on top. So use very very very very very sparingly, rub it in good, and use plenty of light laps and bobs yer uncle. Seriously, this works great for me. But don't try it if you just don't feel the vibe. More than one way to gitter done.

Would it be best to rub it in by hand?

Or is there a pic showing a better method. I get the idea of using the least amount needed, just want to keep from mucking it up.
 
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