Using soap stone for honing?

[Legion]

Wdwrx, there are some interesting ideas you put forward here. I'm not sure I agree with everything, but I like that you are prepared to back the ideas with experimentation.

While I don't argue the point that a soft material can abrade a hard one, after all, given enough time even something as soft as water will cut a channel in stone. But can it do it in a controlled enough way to sharpen? In the case of the soapstone, the stone would work so slowly on the steel that the stone would Be worn into a hollow, and it would not be creating a flat bevel, but a rounded edge. I'm in bed writing this on my phone. I need to think about it some more.

An interesting mental exercise, as you said.

 

[honed]

For those inclined I saw that you can buy a good chunk of soap stone on eBay for a BIN price of 0.99 USD.

 

[wdwrx]

....But can it do it in a controlled enough way to sharpen? In the case of the soapstone, the stone would work so slowly on the steel that the stone would Be worn into a hollow, and it would not be creating a flat bevel, but a rounded edge.

ah ha! that is exactly the question. And I really don't know. I do agree that is exactly what will probably happen. Otherwise, we would all be bragging up our new soap-stone acquisitions.
I'm off to ebay to see what I can find, cheap. (Thanks Honed)

 

[Woodash]

Something like a solid talc in a smooth flat substrate might offer a high degree of polishing simply because of that function, but still allow one to keep a perfectly flat bevel.

It's not all about hardness of the minerals, per se. The hardness of the clay minerals that are dominant in many (most) Jnats and BBW are only slightly harder on the moh's scale. Hard soapstone is used all the time for polished countertops and woodstoves, etc. Soapstone is also similar to a BBW in many ways - both phyllitic, both dominated by relatively coarse clay mineral species.

I didn't think you were talking about creating a flat bevel Chris, just maintaining one during a polishing step, and for a high-grade talc phyllite (possibly a talc schist) that has been cut, polished, and lapped, I think it may well be possible. Who knows? I say go for it...

 

[wdwrx]

I hadn't envisioned actually creating a bevel either, Steve, rather a just few laps of an already finished edge. I have no doubt that it wouldn't be suitable for much more, for all the reasons Legion has pointed out.

I had no idea that counter tops were made out of soap-stone. Ya learn something every day... It's apparently a harder soapstone than the pieces I've seen carved into inuit art which seemingly has a higher talc content.

Ebay.ca wasn't a bonanza either; very pricey for large pieces, or too small, or already carved into a nice piece of art.
Honed, would you mind sending me a link to the auctions you found?
There is a rock and gem store here, locally; I'll make it a point to stop in there this week and see if they have anything close to about 1"x4".... cheap. Barring that, I know I can get welder's pencils made of soapstone, that would do to either prove or disprove the idea.

 

[Woodash]

I had a look over there. This may be what Honed was talking about:
http://cgi.ebay.com/High-Quality-So...697?pt=LH_DefaultDomain_0&hash=item4cf39d8701

Be aware of the fact that the seller mentions that "Photo's are an example of what the Soapstone looks like when finished," so you may be getting something pretty rough. You might want to have a look at the address that he puts in his auction (http://www.soapstone4carving.com/) and see if he'll sell you a cut block.

 

[honed]

I hadn't envisioned actually creating a bevel either, Steve, rather a just few laps of an already finished edge. I have no doubt that it wouldn't be suitable for much more, for all the reasons Legion has pointed out.

I had no idea that counter tops were made out of soap-stone. Ya learn something every day... It's apparently a harder soapstone than the pieces I've seen carved into inuit art which seemingly has a higher talc content.

Ebay.ca wasn't a bonanza either; very pricey for large pieces, or too small, or already carved into a nice piece of art.
Honed, would you mind sending me a link to the auctions you found?
There is a rock and gem store here, locally; I'll make it a point to stop in there this week and see if they have anything close to about 1"x4".... cheap. Barring that, I know I can get welder's pencils made of soapstone, that would do to either prove or disprove the idea.

I didn't see you were north of the border...
Maybe the can ship outside US?

Anyway, this was the one I reffered to first:
http://tinyurl.com/36e6aw4


There also a bunch of other sellers, selling soap stone w/ BIN

 

[honed]

I had a look over there. This may be what Honed was talking about:
http://cgi.ebay.com/High-Quality-So...697?pt=LH_DefaultDomain_0&hash=item4cf39d8701

Be aware of the fact that the seller mentions that "Photo's are an example of what the Soapstone looks like when finished," so you may be getting something pretty rough. You might want to have a look at the address that he puts in his auction (http://www.soapstone4carving.com/) and see if he'll sell you a cut block.

Yes it was.

 

[wdwrx]

Thanks guys.
I'll fire him off an email. I'd buy that for a buck!

 

[Munxcub]

While emailing with Terry about other things, I mentioned to him an idea I had for this. What about using it like a balsa strop with CrOx or something. If it it soft enough, perhaps you can get the CrOx embedded in the material and then use it like a Soapstone/CrOx hone?

There was doubt that it was soft enough to embed CrOx into.

 

[TedK]

Something like a solid talc in a smooth flat substrate might offer a high degree of polishing simply because of that function, but still allow one to keep a perfectly flat bevel.

Uh, no.

Soapstone is sold as soapstone because it feels slick. The slickness is talc (Magnesium Silicate Hydroxide). If the soapstone isn't pure talc, then the stone will not feel so slick. Only the contaminating stone can be a number of mineral hosts or relatives all with different levels of hardness.

The quote above, deals with whether talc will ever reach a hardness sufficient to scratch steel not to mention whether the grit size involved will polish steel. The answer is no! Talc has a MOHS hardness of 1; the mineral variants that are called soapstone are Saponite and Steatite. Steatite is basically pure talc, Saponite chemically is very similar to talc (Ca0.25(Mg,Fe)3 (Si,Al)4 O10 (OH)2· nH2O ) and has a hardness of 1.5 - 2.

At these levels of hardness, soapstone will never scratch or polish steel. If the soapstone is partially composed of other minerals, say quartz, then yes, it could scratch steel. Only the scratches will be based on the size of the quartz inclusions which will most likely be random sizes.

Quartz is silicon dioxide. Arkansas stone (Novaculite) is a kind of sandstone comprised of fossilized diatoms. What makes novaculite so useful for sharpening are the evenness silica dioxide skeleton sizes and their fossilized (opalized, silicon doxide) connections to each other so that they wear evenly (water stones use a similar even wear modus operandi). The hardness of silicon dioxide (quartz in mineral form) is just enough so that it abrades most steel alloys and temperings, though not necessarily all.

All of the preferred polishing/sharpening agents:
Rouge (ferric oxide, rust) hardness 6.5,
Alumina (aluminum oxide) hardness 9,
corundum hardness 9,
silicon carbide hardness 9.5,
cerium oxide (usually the white bars sold for polishing) hardness 8,
Green Rouge (Chromium Oxide) hardness 8.5,
Infused Alumina (hydrate-calcined) hardness 8.5 - 9 (better for polishing steels than plain alumina) and finally
Diamond (crystal carbon) hardness 10.
Are harder than plain steel, many are far harder. Personally I prefer diamond and arkansas stones for basic sharpening and cerium oxide an diamond pastes for final polishes.

The rub, high carbon steel refers to the Widmanstätten and other carbides formed along with the steel crystal structures during the heat treating (tempering) process. An effective sharpening polishing compound must be hard enough to evenly wear down all of these blade components simultaneously. Avoid the soft stuff if you want flat even bevels.

If you want a final test; rub the back of your fingernail across the soapstone. If it won't polish your fingernail, it certainly won't polish your razor.

Just my opinion,

TedK

 

[TedK]

I see the thread moved on while I was compiling my post...

Some more comments (opinion statements in other words)

Check your phone book! Soapstone is common and can often be found sold nearby.

Soapstone is heavy! Those $1 ebay pieces can not be large if they're being shipped expedited (priority mail) for $4. Kind of tough to lap a 4" blade on a 2"X3" block.

Soapstone used for counters is not harder. In fact the sellers will often tell you that you can use any part of the counter as a cutting board and that it will not damage the knives. They will tell you that cutting on the counter will leave scratches, but refinishing is just a sanding and wipe with mineral oil.

Balsa wood will hold the polish, but the cellular structure of the wood may not give best results (hold a lot of polishing agent, but expose only a little to the blade). Copper, tin, plexiglass, felt and leather are often used in the jewelry trade for polishing stones (faceted and cabochon). The idea is that the polishing agent will imbed into the softer surface but be exposed at that surface.

TedK

 

[binowatch]

the leather in a strop isn't what does the edge ruining, its the silica in the air that embeds itself in the leather that does it. Technically speaking the hardness of things is what either abrades or not. Wood will never in a million years cut steel and much less something like a diamond. Hence since nothing is harder than a diamond except maybe nano tubes, nothing will ever scratch a diamond except another diamond. Even our hands are abrasive when particles of other hard minerals embed themselves in them. Some dude from my home town, a barber, used to go to a place where they literally wash sand for concrete, he said all the minerals that come out of the sand were good for treating strops??? So I went there and there is literally a river of very very fine sediment got a sample rubbed some on a strop and voila works like a charm. Turns out that most of that sand is none other than.... SILICA!

My organic chem prof recalled a professor of his who taught crystallography. Whenever he couldn't get things to precipitate/form crystals he would gently stroke is long, dense, red Scottish beard and poof-it would go. He carried all nature of micro crystals in his beard, they would fall into solution as a nidus of crystalization and start the process! This raises question of where we should hang strops etc. Great discussion.

 

[rambus007]

Wow I'm glad my thread has raised so many questions and ideas. I have been to Lee Valley and have seen a block of soapstone for $9 (or was it $19). I'll see if I can pick up a piece and give it a try. My original idea was actually to use the soapstone for polishing, not for setting a bevel because I knew that soapstone was soft. I discussed this with Munxcub and he suggested putting a bit of CrOx on the smooth surface and treat it as a strop; similar to a balsawood strop. The problem is I don't have any 0.5 micron CrOx. I am trying to order 2 micron CrOx but the company hasn't replied to my email. Is there someone willing to send me a small sample of CrOx for this experiment please?

 

[Legion]

Wow I'm glad my thread has raised so many questions and ideas. I have been to Lee Valley and have seen a block of soapstone for $9 (or was it $19). I'll see if I can pick up a piece and give it a try. My original idea was actually to use the soapstone for polishing, not for setting a bevel because I knew that soapstone was soft. I discussed this with Munxcub and he suggested putting a bit of CrOx on the smooth surface and treat it as a strop; similar to a balsawood strop. The problem is I don't have any 0.5 micron CrOx. I am trying to order to 2 micron CrOx but the company hasn't replied to my email. Is there someone willing to send me a small sample of CrOx for this experiment please?

Here is the problem I see with this idea. I suspect putting CrO on a piece of flat soapstone will work for polishing a blade. For a while. Then the soap stone will get dished and you will have to lap it, which will wipe all the CrO off the stone.

This is like saying if you put CrO on a slice of apple it will polish a razor. Yes... possibly... but it is the CrO polishing, not the apple. Why bother using something as a platform for the polishing agent that is going to be less suitable than ones we use already?

On the other hand, go ahead and try if you want. I could be wrong (it's happened before ) and this could work better than anyone hoped. Probably worth a try if someone locally can pif a bit of CrO your way. You can always carve the soapstone into something later.

 

[rambus007]

Here is the problem I see with this idea. I suspect putting CrO on a piece of flat soapstone will work for polishing a blade. For a while. Then the soap stone will get dished and you will have to lap it, which will wipe all the CrO off the stone.

This is like saying if you put CrO on a slice of apple it will polish a razor. Yes... possibly... but it is the CrO polishing, not the apple. Why bother using something as a platform for the polishing agent that is going to be less suitable than ones we use already?

On the other hand, go ahead and try if you want. I could be wrong (it's happened before ) and this could work better than anyone hoped. Probably worth a try if someone locally can pif a bit of CrO your way. You can always carve the soapstone into something later.

Yes indeed. I guess I can make some sort of stand to hold my razors if this doesn't work out. It might take me many months though. I haven't used a balsawood strop for very long. I made some but I don't have any polisher to put onto the surface so they are collecting dust now. If the soapstone is expected to dish, can't we say the same for balsawood? I haven't used mine long enough to know this so I'm hoping someone with a balsawood strop will chime in and comment. If balsawood can stay flat then I would imagine soapstone would too if you are only stropping and not honing as I originally planned for this experiment.

 

[Woodash]

​

Uh, no.

Soapstone is sold as soapstone because it feels slick. The slickness is talc (Magnesium Silicate Hydroxide). If the soapstone isn't pure talc, then the stone will not feel so slick. Only the contaminating stone can be a number of mineral hosts or relatives all with different levels of hardness.

The quote above, deals with whether talc will ever reach a hardness sufficient to scratch steel not to mention whether the grit size involved will polish steel. The answer is no! Talc has a MOHS hardness of 1; the mineral variants that are called soapstone are Saponite and Steatite. Steatite is basically pure talc, Saponite chemically is very similar to talc (Ca0.25(Mg,Fe)3 (Si,Al)4 O10 (OH)2· nH2O ) and has a hardness of 1.5 - 2.

At these levels of hardness, soapstone will never scratch or polish steel. If the soapstone is partially composed of other minerals, say quartz, then yes, it could scratch steel. Only the scratches will be based on the size of the quartz inclusions which will most likely be random sizes.

Quartz is silicon dioxide. Arkansas stone (Novaculite) is a kind of sandstone comprised of fossilized diatoms. What makes novaculite so useful for sharpening are the evenness silica dioxide skeleton sizes and their fossilized (opalized, silicon doxide) connections to each other so that they wear evenly (water stones use a similar even wear modus operandi). The hardness of silicon dioxide (quartz in mineral form) is just enough so that it abrades most steel alloys and temperings, though not necessarily all.

All of the preferred polishing/sharpening agents:
Rouge (ferric oxide, rust) hardness 6.5,
Alumina (aluminum oxide) hardness 9,
corundum hardness 9,
silicon carbide hardness 9.5,
cerium oxide (usually the white bars sold for polishing) hardness 8,
Green Rouge (Chromium Oxide) hardness 8.5,
Infused Alumina (hydrate-calcined) hardness 8.5 - 9 (better for polishing steels than plain alumina) and finally
Diamond (crystal carbon) hardness 10.
Are harder than plain steel, many are far harder. Personally I prefer diamond and arkansas stones for basic sharpening and cerium oxide an diamond pastes for final polishes.

The rub, high carbon steel refers to the Widmanstätten and other carbides formed along with the steel crystal structures during the heat treating (tempering) process. An effective sharpening polishing compound must be hard enough to evenly wear down all of these blade components simultaneously. Avoid the soft stuff if you want flat even bevels.

If you want a final test; rub the back of your fingernail across the soapstone. If it won't polish your fingernail, it certainly won't polish your razor.

Just my opinion,

TedK

Uh...We’re talking about soapstones here, not hydrothermal talc deposits, and certainly not saponites. There are plenty of hones out there dominated by micas that polish a bevel quite well.

 

[binowatch]

I think I still remember the hardness scale from 7th grade earth science-talc/gympsum/calcite/flourite/appetite/feldspar/quartz/topaz/corundum/diamond! Is that right- if so talc is a far distance away from corundum and diamond which are typical abrasive stones. As indicated above I suspect the abrasive power of some of the stones mentioned is really from minor components of quartz and on up.

 

[Woodash]

I think I still remember the hardness scale from 7th grade earth science-talc/gympsum/calcite/flourite/appetite/feldspar/quartz/topaz/corundum/diamond! Is that right- if so talc is a far distance away from corundum and diamond which are typical abrasive stones. As indicated above I suspect the abrasive power of some of the stones mentioned is really from minor components of quartz and on up.

Correct, but (natural) hones are not pure phases, right?

 

[binowatch]

aren"t pure phase minerals minerals with a fixed composition? Ah, natural hones will have varying compositions, presumably including minerals/elements with a higher Mohs score, yielding variable hardness. Wouldn't this be a problem with a natural vs synthetic stone when used for razor honing? If your really want to know the fineness off the hone and its hardness would'nt a sythetic be better. I ask because I have made the leap to start using a straight and was thinking about what hones to get and have gotten more confused the more I read. I have about 10 straights that were my Dads and his uncle's (who was a barber)-all used, most in really good shape but most have not responded to just a stropping, so I think I need to hone them. I'd like to learn to do it myself. thanks