Surgical Black

[professorchaos]

Instead of caving to the incessant pressure to hone my razors on lapping film, which I find to be utterly soulless, I caved and picked up a surgical black Arkansas.

Having never used one, I'm interested in a few pointers. My understanding is that to get the most out of it, it will need to be lapped then the surface refined. So some questions ...

1. Can these be lapped under running water?
2. I was planning on "honing" a cleaver on it to refine the surface. Alternate suggestions?
3. Generally speaking, how slow are Surgical Blacks?

 

[SliceOfLife]

I've done it by rubbing two SB's together. Works but takes AWHILE to clean all the grit out (honing with oil and flushing a bunch), so probably doesn't save any time. Cleaver strat sounds like a better idea. You could lap under running water, but they are so hard I prefer to do it flat and rinse alot so you can use more pressure. They are slow, but not the slowest thing out there. With pressure they actually aren't terrible, but they cut like a midrange hone with pressure. Most razor honers seem to use em without much if any pressure just to burnish the bevels on already finished razors, they're very slow at that. Slow enough you never are really "done" with it. You could do a thousand laps and it'd still be improving. Probably ten thousand and it'd still. It's just BARELY more effective than honing on glass.

 

[Disburden]

When you lap it, be ready to spend a few days to get it flat and smooth. Mine is so hard it took four days of lapping at about 45 minutes a session. My arm was killing me, and I killed my DMTs in the process.

They are slow, I use oil on mine. It's true you can do 1000 laps and still see improvement. I have done 400 laps on mine before and still saw improvement being done. They are fun hones.

 

[oakeshott]

Henry,

I've lapped a couple of translucent and SB arkies this year and dramatically sped up the process by using SiC powder. I used 200 and 400 grit, but on reflection, I'd recommend starting with 400 and then going up from there. You'll get it flat pretty quickly with SiC powder and then go up a couple of grits to accelerate the smoothing.

The longest part is getting them to that degree of smoothness that makes them a real finisher. I use W/D up to 2k and the arkie eats it up like potato chips. The next phase of getting it smooth I've not really mastered so other people will have better advice. On the initial lapping for flatness though, I don't know of anything that works faster than the SiC powder.

 

[Gamma]

I lapped mine on DMTs until the stone was as flat as that was going to get it.
Then - I lapped on w/d starting at 100x, or 150x. I forget.
I used - ALOT - of w/d. I went all the way to 2k I think,
Then - I ran chisels, with pressure, over the top for a while.

I've used SIC powder recently - I find that it's not all that accurate. IF - I ever lap another Ark, I'd use it for the initial lapping to cut off as much material as possible but after that I'd move to w/d. It's way too easy to bevel the stone's top using that powder. But - it's way fast. It does a great job of wiping out DMT gouges so I might be inclined to try a 600x-1k SIC powder.

Maybe it's me, but I find that these stones have way less tolerance for being out of 'flat' that any other stone.

My SB Ark gets me 'there' after I hit around 300 laps or so. I don't count laps usually, but I did with that stone because 10 laps didn't do spit and neither did 50. So I just went for 300. The feedback at that point is sort of easy to identify, so subsequent honings don't need to be counted out. I use a tinge of Dawn dish soap on mine. I've also used Glycerine/water. I dislike using oil and I'm not convinced that using it does anything that good 'touch' on the stone doesn't provide. I would like to try that oil-free honing solution sometime though.

 

[Krodor]

That last bit of prep: was recommended that I use a flattened BBW to help polish it. That worked fairly well, but yeah, as has been said, once it's "done", the use of the rock as a finisher seems to be eternal. For fun, I've been giving the same blade 50-100 passes or circles every couple nights lately (GD66), and it just gets better.

 

[professorchaos]

Thanks gents.

It is an interesting hone. I've lapped it and run a cleaver over it a few hundred times.

My plan is to hone two razors similarly up to the finisher. Razor one will get the J-Nat finish. Razor two will get a couple of hundred laps on the SB. Then a test shave. I'll repeat the process with the second razor until it is smooth shaving sharp.

 

[PapaFish]

Henry,

I've lapped a couple of translucent and SB arkies this year and dramatically sped up the process by using SiC powder. I used 200 and 400 grit, but on reflection, I'd recommend starting with 400 and then going up from there. You'll get it flat pretty quickly with SiC powder and then go up a couple of grits to accelerate the smoothing.

The longest part is getting them to that degree of smoothness that makes them a real finisher. I use W/D up to 2k and the arkie eats it up like potato chips. The next phase of getting it smooth I've not really mastered so other people will have better advice. On the initial lapping for flatness though, I don't know of anything that works faster than the SiC powder.

I'll echo the SiC. I got a tablespoon or so amount of 200 grit and used it to get a couple large Arkansas Hones most of the way flat. I have ordered 200 grit, 600 grit, 5 micron, and 1 micron. There should be way more than I need to finish the job, and take me to a much higher polish than needed, but I would rather error on the side of caution, and plus, the goal is to have all the sides of 4 of the stones (a full progression) flat .
The fastest method that I have found (that keeps the hones flat) is to take some 220 w/d, secure it to a flat substrate (I use binder clips to hold it down to a custom sized marble tile, spray adhesive on a tile might work better), add some powder, and lap away. I keep things dry, I find it prevents lots of problems. Keep adding powder long after the grit is all gone from the paper. The paper protects the tile from dishing, and allows you to just keep working. I tried a lot of things, but this seems to have worked the best. I plan to use:
200 powder on 220 w/d,
600 on some 500 w/d,
5 micron on some 1200 w/d,
once two stones are flat and good up to this level, I will use the 1 micron in a wet slurry between them until they absolutely gleam like glass. Well, that's the plan anyhow. Perhaps I will have some flat, smooth hones for the holidays .
After the 1 micron slurry, I will most likely need to still break the hones in. I have been told SEVERAL razors can do it, or several hours of trying to remove a chip, or set a bevel on a razor might do it. Make sure your cleaver can get to all the edges and corners. A straight edge will help I am sure. I have 3 razors with straight edges lined up that all need a bit of work, so that's my plan.
Depending on the size of the hone, I have heard several hundred to 1000 strokes being needed. I think the small ones (4"x2") need a lot more passes, and the larger 8"x3" (or bigger) types need just 2-300 .

 

[Gamma]

Thanks gents.

My plan is to hone two razors similarly up to the finisher. .

What stone are you using as a 'pre-finisher'?

 

[Alum of Potash]

I've [. . .] run a cleaver over it a few hundred times.

Then you're probably good to go.

I have a question, what makes it a "surgical" black? I use my Arkansas stones with honing oil, finding it neater than water as it doesn't have a tendency to splash everywhere. Just enough to thinly cover the surface does the trick for starters. Nitrile gloves allow the tactile sensation to remain, while cutting down on the "icky" factor.

Pressure is good with Arkansas stones. I go with the way things feel. Rather than use a count-based approach, a time-based approach may be easier. 15 mins. here, 15 mins. there, 5 mins. here, 5 mins. there, etc.

 

[oakeshott]

Then you're probably good to go.

I have a question, what makes it a "surgical" black?.

They were marketed as hones to sharpen surgical instruments.

 

[SliceOfLife]

Word from the mine I spoke with is that they determine a surgical black vs a black hard based on how hard it is. Told me it once took 3 hrs to make a single cut on one piece of surgical black. By contrast your standard hards, which can be found in black, are relatively easy to cut.

 

[professorchaos]

What stone are you using as a 'pre-finisher'?

That remains to be determined. Any suggestions? I am considering Shapton Pro 12K.

 

[Oscroft]

I find the idea of rubbing for ages for slow and gradual improvement quite appealing. Where would one obtain these Surgical Black stones? Would something like this be the real deal?

 

[professorchaos]

I got mine from Dan's.

 

[Seraphim]

What does rubbing the cleaver do for the hone?

 

[Steve56]

Most likely knocks the tops off the grit and smooths the grit edges out, like a worn Atoma or worn sandpaper vs fresh.

Cheers, Steve

 

[PapaFish]

From what I've gathered, the good ones are all super dense, and a good indicator of density is that the stone is translucent to some degree. It's the easiest way to make sure the density is super high. There are Black Translucent stones, but I think other places just call them Black, or maybe Surgical Black. You can check for translucency with a flash light around one of the edges. You don't have to light up the whole stone, just have some.
Rubbing the clever after smoothing the stone as much as you can just continues to smooth the stone. I'm not exactly sure, but I see it as filling in voids with steel, removing unwanted grit from the pores, and knocking high points off what remains. All three of these might be wrong, I just understand that it works .

 

[Oscroft]

I got mine from Dan's.

Thanks!

(Interestingly, that Amazon seller seems to be offering them cheaper than direct from Dan's)

 

[Seraphim]

Anybody compare a surgical black to say, a Spyderco Ultra Fine?

They sound similar (extremely hard, hundreds of laps for very slow refinement)

EDIT: or a Chinese 12K for that matter.

Whats the difference?