Stropping Compound Question

[Dr Rez]

So I have a quick question I could not find a direct answer to when browsing bladeforums/reddit. To give you some background I am pretty proficient with whetstones and for most knives up to beginning supersteels like s30v I go up to a 6000 grit stone, then go to my leather strop and use a black compound then finally to the green compound. This gets my knives about as sharp as I want, able to push cut paper, shave, etc...

So my question is in which compound I should buy to reapply to my strops. The old compound they came with is finally almost completely worn off. Do you simply just go based off color? What I mean is will all green polishing compound be the same, and all black buffing compound work? I also do not understand if I would want to just finish with black then green as I see many other colors like red and white which I assume are different grits.

Any clarification on this would be great. I have a 1 pound chunk of green polishing compound and a pound of black buffing compound picked out online should I just go ahead with those since I seems to be working well so far?

 

[Gvard]

The one rule would be not to apply a higher grit compound finish on a strop that had been treated with a lower grit finish. The colours don't always indicate what the particle size is. The green compound usually contains chromium oxide though, so any green compound should give you the same finish. If you know where you bought the strops from, you could ask what compound they used or, my preferred method, buy some leather, make your own strops and apply the compounds you want on a fresh strop.

 

[Obsessed with Edges]

For S30V and similar steels with vanadium at/above ~ 3% or so, you'd be better off with a diamond or cbn compound. Green compound does OK with the 'matrix' steel in such blades (excluding the very hard vanadium carbides), but won't add much refinement to the carbides themselves. Diamond & CBN will be the only compounds actually hard enough to shape & refine those carbides.

Green compound works best with simpler carbon and low-alloy stainless, like 1095, CV, 420HC, 440A.

The black compound will work with simple and mid-high wear-resistant steels (up to 440C, 154CM, D2, etc) usually leaving a somewhat coarser finish than green.

Might also look into 'white rouge' (aluminum oxide) for essentially the same steels listed above for the black compound. I like it better for higher, finer polish on such steels, and it's great for burr cleanup on steels with known tenacious burring issues (VG-10, etc).

 

[Mo2]

I would.not mix other compounds on your strops. You don't want to contaminate them. Either find the same compound it has on it or get some new strops. You can probably just get some new leather and remove the old and put a new one on.

You can also find some really cheap diamond paste that I would suggest for s30v.

 

[Dr Rez]

Thanks for all the advice I will buy a second one for a diamond compound. So on the website for my strop they had this "black (3, 000 grit) and one side is green (6, 000 grit)" Anyone know any good place/company to get these compounds from?

Also I can not find any diamond compound to purchase, and points int he correct direction?

 

[Bill DeShivs]

Most black emery compounds are actually about 300-400 grit, and the green compounds 600-800 grit.

 

[Obsessed with Edges]

Thanks for all the advice I will buy a second one for a diamond compound. So on the website for my strop they had this "black (3, 000 grit) and one side is green (6, 000 grit)" Anyone know any good place/company to get these compounds from?

Also I can not find any diamond compound to purchase, and points int he correct direction?

Many here have used & liked the spray emulsion compounds from Ken Schwartz (for diamond, cbn) and DMT, for example. I've used DMT Dia-Paste, and it works fine. But there are LOTS of options out there; might take some time to read more here on the forum, to see what people are trying out and finding useful.

Bark River seems to be pretty popular for the standard compounds in green, black, etc. But again, there are LOTS of options for those too. Even hardware store-type buffing compounds (made for bench grinder-driven buffing wheels) can work pretty well. I've used such compounds from Ryobi (my white rouge) and Sears, for example, and have found them useful. I like using them on hard-backed denim/linen strops, which take and hold these wax-bound compounds more easily than with leather.