Thread: washita confusion

Oh they can still put in a little work, but if you try removing much steel you'll be there a very long time without a whole lot of progress. A modern synth will absolutely destroy a natural stone for heavy cutting on some of the tougher steels. The Washitas and Arks can still put a finishing touch on most steels though. There are certain steels that even synths won't cut very well as far as heavy work. These are things like High Speed Steels and S30V, etc. at very high hardness levels - and even when they do cut the edge will be pretty ragged on the microscopic level if using a coarser stone, with a lot of pulled out carbides. I recently made a razor from HSS and a Chosera 1k would barely touch it when I was setting the bevel. It just skated on a Washita. I ended up using diamond plates and that worked great.

Originally Posted by eKretz

Oh they can still put in a little work, but if you try removing much steel you'll be there a very long time without a whole lot of progress. A modern synth will absolutely destroy a natural stone for heavy cutting on some of the tougher steels. The Washitas and Arks can still put a finishing touch on most steels though. There are certain steels that even synths won't cut very well as far as heavy work. These are things like High Speed Steels and S30V, etc. at very high hardness levels - and even when they do cut the edge will be pretty ragged on the microscopic level if using a coarser stone, with a lot of pulled out carbides. I recently made a razor from HSS and a Chosera 1k would barely touch it when I was setting the bevel. It just skated on a Washita. I ended up using diamond plates and that worked great.

Interesting. I guess I don’t own a knife or razor like that. I figured the Vanadium knife would have been pretty hard steel. I didn’t have any problems but it must not have been steel like you are talking about. I’m sure someday I will run into something similar but I just haven’t yet. Thanks.

I never really thought much of it either until hitting some of the harder steels with carbides. The razor I made recently was from T15 HSS, so should have been tungsten carbides - hardness was probably about Rc65 - 66 if I had to guess. The Chosera 1k couldn't even pull enough swarf to turn black when used with a DMT slurry. Tough stuff indeed.

Reading this thread has convinced me that two white stones that I have are lily whites. I love them for knives. Thanks to everyone for this helpful thread.

The geologist in me wanted to look deeper.

Arkansas stones are novaculite:
Wikipedia has this paragraph...

"Novaculite is a form of microcrystalline or cryptocrystalline quartz. The color varies from white to grey-black and the specific gravity shows an increase from 2.2 to 2.5. The very hard dense rock is used as a whetstone; whetstones of this material are described as Arkansas stones. It has been mined since prehistoric times both as material for use as arrow and spear points and as sharpening stones.[2] Moreover, the upper strata of Arkansas Novaculite, known as tripoli, has found a niche within the coatings, adhesives, sealants and elastomer industry as a performance additive or filler. Tripoli is mined just east of Hot Springs, Arkansas by Malvern Minerals Company.[3]

"The word novaculite is derived from the Latin word novacula, for razor stone."

The microcrystalline or cryptocrystalline bit means the crystals are too small to "see" with the eye or
even a hand magnifying glass. It also implies that the crystals are in a random distribution.
Hardness... hardness is listed as 7: not scratched by knife. This implies that steel can be scratched
by quartz. Hardness varies with direction... HARDNESS, Penetration is 30.8X103 kg/cm2 parallel to
the 'long' Z 22.9 perpendicular to Z. This hardness feature implies that the surface of a dense mass
of crystals will wear slightly unevenly.

The density of quartz (how tightly packed) and the size distribution is what makes for the different grades
of Arkansas stones. Densely packed tiny crystals will give the finest scratch pattern after the surface is burnished
to remove the scratches left by the saw or lapping process.

Quartz is not hard enough to directly abrade carbides but can deform the steel around tiny carbides
even pushing them back into the steel or abrading the quartz.

Hardness of steel before tempering is apparently harder and more brittle than quartz
and plastic deformation is limited. A steel file is about 6.5 mohs hardness. Steel
untempered is brittle like glass and will chip rather than deform gracefully in the sharpening process.

https://micro.magnet.fsu.edu/primer/...litesmall.html

The denser and smaller the micro crystals the better (finer) the hone.
It is not a slurry friendly hone. A rough surface from lapping can haunt these hones
for months.

They are natural and will vary...
The good ones with the right steel makes believers...

Consider finish burnishing with Bon Ami 1886 Original Formula and mild steel.
The feldspar is softer than the quartz and breaks down nicely.

I got my first 'arkie' about the same time Buck stainless steel knives came out
in the mid and late 60's. They were almost worthless at 'sharpening' the
new stainless buck knives.

Recommendation... lap flat with a DMT or grit in a steel pan.
Eliminate scratches with something like 3M wet or dry paper
down to 3000 grit or finer then gently burnish with a bit of flat mild steel
stock. Use water, lather or oil and a light hand for razors. The good ones
will possibly finish a razor better than sharpen it.

Originally Posted by niftyshaving

I got my first 'arkie' about the same time Buck stainless steel knives came out
in the mid and late 60's. They were almost worthless at 'sharpening' the
new stainless buck knives.

Truer words have never been spoken. Man, I spent hours on my 110 and 112 trying to get those hairs a poppin'.

Originally Posted by niftyshaving

Recommendation... lap flat with a DMT or grit in a steel pan.
Eliminate scratches with something like 3M wet or dry paper
down to 3000 grit or finer then gently burnish with a bit of flat mild steel
stock. Use water, lather or oil and a light hand for razors. The good ones
will possibly finish a razor better than sharpen it.

My experience as well.

Originally Posted by kelbro

Truer words have never been spoken. Man, I spent hours on my 110 and 112 trying to get those hairs a poppin'.



My experience as well.

Washitas will actually pull the carbide out of alloy steel with big carbide. I have pictures that I took here somewhere (I have a metallurgical scope). A trans stone follow up will help mitigate some of the damage, but you still have to get the wire edge off of a knife without damaging the edge.

The other issue is hardness. Washitas will cut soft steel deeply, and depend on properly hardened steel to mitigate that to some extent. Stainless in older knives was soft for a variety of reasons.

I have literally honed hundreds of razors on NOTHING but Washita stones and Arkansas. I started my honing with synthetics, then went to synthetics/naturals (Guangxi, Coticule, oil stones, etc,) and then for the last 2+ years I have been honing exclusively on Washita/Arkansas stones. I am not talking about theories or possibilities here. They are very capable of finishing a razor and setting a bevel. I have done it hundreds of times with razors. What a wonderful edge they produce too! You just have to know what you are doing and then practice.

Here is a Lie Nielsen A2 Iron that has been sharpened with a washita stone.

https://postimg.org/image/9bmy99vy57/

(this doesn't load on my work PC, but it's probably my filter). I can trim the image and put it up here via another host if needed. At any rate, if you can see it, you see the little holes at the edge. I believe those are carbides being pulled out. It happens on the chisel bevel itself, too, but it's exacerbated at the edge. This is fully and freshly sharpened, and would be far finer carbides (it's cryo treated) than old stainless. I think it was probably a losing proposition to sharpen those old knives with stones that have a bit of "grip" but won't cut into chromium carbides.

Here is a japanese chisel sharpened with the exact same stone.

https://postimg.org/image/3zvaaebq4r/

Apologies for not finishing the edge and then taking a picture. This is a chisel that I use to cut plane mortises, so it takes a lot of damage and then just needs to get back to this shape to work. It doesn't need to be perfect, because it won't be for long once the bashing starts. Important point, other than the edge damage that's left, no carbides are coming out.

My dad has two knives that i'd compare, results would be similar to the above:
1) an unbranded stainless knife from the 1960s
2) a surplus camillus air force knife (without blood groove)

He also has a washita and a crystolon type stone. He doesn't like the former because it's "too slow", and he doesn't like the stainless knife because the edge doesn't get refined no matter what. i'm sure that whatever is at the edge of the old stainless knife is a combination of bent metal and chunks missing vs. the camillus knife (which just has deep grooves on it, but is otherwise plenty sharp to minute of deer standards - and that's the only thing he uses it for).

Anyway, here is the same lie Nielsen iron after a trans ark:
https://s1.postimg.org/19oi8u4f5b/LN...ark_honing.jpg

(doesn't rip carbides out and the edge is refined, despite the fact that the actual scratches are not much finer - just a little)

The washita is my favorite stone, but reality isn't always as simple as "this stone works with everything", pretty much for anything. You can fall back to synthetics, but they're not nearly as productive in a shop setting as a washita is. Here's the mortise chisel from above before, after a mortise (a plane mortise is fairly large). 15 strokes on a washita and you can do the next one, and the next, and the next.

https://s1.postimg.org/5jvihj2cj3/Ja...er_Mortise.jpg

Ekrets mentioned above that there are alloys that are too hard to hone on naturals and I believe that even if I haven’t experienced it. I am just tired of all the misinformation on the web about these stones by people who just haven’t put in the time or don’t know what they are doing. If someone can’t get a nice Shaving edge off an 8k or their coticule that doesn’t mean it is not possible. Just not possible for them at their level of experience or with their stones. 5 years ago people were all over the forums saying you could never use an Arkansas stone to finish a razor. Many people have proven that statement false. Not only is it possible but it isn’t even that hard once you know what you are doing. How far our knowledge has come in the past few years regarding these stones and razors. If you can’t manage to get an amazing edge with these stones maybe, just maybe, it’s you and not the stones especially if others are able to do it.
DaveW- thanks for the pictures. They are very telling and interesting.