Buffing compounds for super steels?

dkb45

dkb45

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Dec 16, 2012
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I've had some recent threads that lead me to find out that my black buffing compounds aren't very effective or ideal for shoer steels, namely high vanadium steels like S30V and M390.

I know most standard buffing compounds are either emery (corundum) or AlOx, neither of which are effective on carbides harder than chromium. I found that SiC is hard enough to abrade most carbides, as is diamond, but diamond is very expensive. Are there affordable diamond compounds I haven't found or SiC compounds that I can use to refine after my DMT EEF (3 micron)?

I should add that I do have Flexcut Gold.
 
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Leevalley has diamond Lapping Films that are some what affordable.. Not sure of the cost to performance ratio between the norm, I've not used them before.
 
I totally forgot about diamond lapping film, but the Lee Valley films jump from 3 micron straight to under 1, my finest stone is 3 micron and I don't want to jump under 1.5-2 without a progression (and sub-1 is just way more fine than I could ever need).

I did get to use my 3.5 and 2.5 cheap diamond pastes and they are effective, albeit unsurprisingly slow cutting. The size seems to be about right on what the grit they claim is, but the pastes are pretty low on grit.
 
dkb45 said:
I totally forgot about diamond lapping film, but the Lee Valley films jump from 3 micron straight to under 1, my finest stone is 3 micron and I don't want to jump under 1.5-2 without a progression (and sub-1 is just way more fine than I could ever need).

I did get to use my 3.5 and 2.5 cheap diamond pastes and they are effective, albeit unsurprisingly slow cutting. The size seems to be about right on what the grit they claim is, but the pastes are pretty low on grit.
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Why do you think you need a progression to move from 3 micron to 1 micron? Have you examined the edge closely to see if the 1 micron is unable to remove the scratch pattern of the 3 micron? If so, have you tried using a lighter touch on all your sharpening, but especially at the 3 micron and lower level?

I ask because most makers of DLF follow the same progression: 30-15-9-6-3-1-.5-.1 . In fact, I don't know of a source for a DLF between 1 and 3 microns.'

FWIW, I've found that 1 micron DLF removes the scratch pattern from 3 micron just fine. That's why I have all these questions.
 
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You can also moderate the effect of any given grit by varying the hardness of the substrate used underneath it. This is why a 3-micron diamond paste used on a wood strop will produce a much higher polish (mirror) than the same 3-micron grit embedded onto a nickel & steel diamond plate (hazy near-mirror). For sandpapers or lapping films, adding a single layer of plain paper between the film/sandpaper and the hard backing will lessen the aggressiveness of the abrasive and therefore produce a finer finish. The caveat is, it'll work a bit slower as well. And you'll need to keep the pressure applied very light as well, so the 'softer' substrate under the grit won't compress excessively and round over the edge.

The above probably isn't really necessary though, in bridging the gap from 3-micron to 1-micron. But it's an option that can make a difference, if you want to pursue it.
 
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Diamond lapping film is a good option.

The compound I make for my Washboards has some diamond in it, mixed with a blend of Silicon carbide.

You can get some bulk graded diamond powder from lapidary supply shops and put some on top of a thin application of the flexcut. It all depends on what sort of finish you need or if are just looking to maintain a bright finish on your super steels.
 
You might want to check out the vast selection of compounds that "JapanWoodWorker" has as well as "Garrett Wade Co." The last buffing compound I used restoring an old fixed blade knife that I found at one of the local lakes recently was some dark green stuff that a woodworker friend of mine gave me.

I've also wondered if some of the "jeweler's rouges" would work with these newer/better blade steels. I have a couple of knives with M390 myself and it is a different animal for sure.
 
About 5 to 6 months ago, switched to CBN and happy with the results. Check out Gritomatic and Bark River cbn compounds in a range of µ sizes. For a list of other cbn options, check out https://www.chefknivestogo.com/strops.html. CBN is not cheap, but it'll abrade any steel type and is a great all purpose choice for stropping, in my case.
 
JD Spydo said:
You might want to check out the vast selection of compounds that "JapanWoodWorker" has as well as "Garrett Wade Co." The last buffing compound I used restoring an old fixed blade knife that I found at one of the local lakes recently was some dark green stuff that a woodworker friend of mine gave me.

I've also wondered if some of the "jeweler's rouges" would work with these newer/better blade steels. I have a couple of knives with M390 myself and it is a different animal for sure.
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JD, if the jeweler’s rouges is for polishing gold/silver, most likely it won’t work on steel, especially the high vanadium carbides type, IMHO.
 
I read that Flexcut Gold has titanium oxide in the compound, which is supposed to be harder than most all carbides. Does that mean that it should be effective for vanadium carbide steels? Are there other titanium oxide stropping compounds?
 
dkb45 said:
I read that Flexcut Gold has titanium oxide in the compound, which is supposed to be harder than most all carbides. Does that mean that it should be effective for vanadium carbide steels? Are there other titanium oxide stropping compounds?
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TiO2 (titanium oxide, or sometimes called 'titanium dioxide') isn't anywhere near that hard. On the Mohs scale, it's generally in the 5.5 - 6.5 range, which would be inadequate for even some plain low-alloy cutlery steels, much less the hard carbides in more wear-resistant steels. As a polishing abrasive, it's generally recommended for softer materials.

Titanium carbide approaches the hardness of vanadium carbide, but is still slightly less hard.
 
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dkb45 said:
I read that Flexcut Gold has titanium oxide in the compound, which is supposed to be harder than most all carbides. Does that mean that it should be effective for vanadium carbide steels? Are there other titanium oxide stropping compounds?
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IIRC it has titanium oxide added (and is fired at higher temp) to make the individual abrasive grains tougher. Overall Mohs value is the same but the abrasive bits stay sharp longer, this makes them hold up better to high carbide steel but only on less hard carbides than Vanadium.
 
The more I read and the more stuff I read turns out to be incorrect, the more I realize I just need to find some diamond wax based compound available in stick form, use that, and never look at buffing compounds again. This stuff makes my brain hurt.
 
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