Looking for a Finishing Stone

[Philipp Jaindl]

Short Version: Looking for a slow wearing Stone to finish off after 3µm that can handle small narrow tools.

So yeah has probably been asked and answered often enough and if you ask 5 people how they sharpen you get 10 answers, i know been there done that. Most Info i could find was either somewhat old or not for the Grit range im after.

Now that we got that out of the way I'm looking for a Finishing/Honing Stone. I sharpen pretty much anything on Diamond plates, i got a full range from 150 up to 3µm,
some old Waterstones 120, 220, 400 and 1000 Grit FEPA, and a couple strops with different pastes to finish off.

I'm looking for a, slow wearing, Stone to finish off after the 3µm especially for things like small narrow tools or some carving knives since those tend to dig into softer stones and especially Strops. The grit number doesnt matter too much as long as i get a proper Edge right off the stone. Oh and it shouldnt break the bank im not gonna spend 200€ on one stone. Ceramic is probably the best bet right?

I have used a Belgischer Brocken/Belgian Chunk/Coticule at work before and really like it its a great stone however small tools can and do tend to "dig in" a little and the other problem with them is the good ones are ludicrously expensive for a proper sized benchstone. Theres also a German "Thüringer Wasserstein" i could get thats supposedly somewhere about 2500 FEPA i think thats about 10000 JIS grit, alot of people seem to really like that one for Razors but i have no clue if that one would work for what i need it .

So Spyderco ceramic, Shapton, Sigma? and in which Grit would you recommend.

[Jim Koepke]

if you ask 5 people how they sharpen you get 10 answers

That is likely because someone like me might have 3 or 4 answers.

So a stone that small carving tools will not dig in to the surface. You want a good edge right off the stone. Finally it shouldn't break the bank.

For my oilstone set up when a little more polish is wanted than a translucent Arkansas stone will provide there are a couple of jasper stones on my bench. This can often be found in a lapidary supply store. (gem and mineral supply)

A quick search on jasper stone hones found this:

WHAT GRIT DO JASPER NATURAL STONES HAVE?
Grit terminology is not applicable to natural sharpening stones, including Jasper. The behavior of a natural stone depends on its density and how good it was lapped. However, experts estimate Jasper as 8000 - 10000 JIS.

My two pieces about 2"X5" were less than $20. The ones processed specifically for sharpening will be a bit more. One of the interesting aspects of having a wife who is into gems and minerals is often finding some exotic stones useful for sharpening at found at a yard sale prices.

jtk

[Patrick Chase]

So Spyderco ceramic, Shapton, Sigma? and in which Grit would you recommend.

Given your stated preferences I'd lean towards the Spyderco.

Waterstone finishers tend to be soft, with the Sigmas being softer than the Shaptons in the very high grits. If you find that you have trouble with tools "digging into" a Coticule then any waterstone finisher will probably require an adjustment to your technique. The Spyderco is rock-hard by comparison, and the UF will cut more finely than 3 um diamond.

[Matthew Hutchinson477]

I have a Spyderco ceramic that I've come around to like quite a bit. At first I was a bit annoyed by how slowly it cut. I had been using it dry as per the instructions but a little birdie told me to try using it with water or soap and water. That helped a decent amount. I had also been jumping from a 9 micron diamond stone straight to the 1 micron ceramic stone which is quite a jump. After adding a 4 micron diamond paste to the routine I found that the Spyderco stone leaves a fantastic polish.

[brian zawatsky]

I have Shapton pro stones, and I do not like the 12000 grit stone. I usually go 1k, 5k, 8k. I can get a mirror polish off of the 8k and an edge where the hairs literally jump off my forearm. So anyway, if you go Shapton, I’d go with an 8k. It’s possible I’m just missing something on the 12k, but so far I find it pretty unnecessary.

[Warren West]

Given your requirements. Forget water stones.

Having been there and done that. Here is what I suggest.

In order of speed slowest to fastest
1. Translucent Arkansas
2. Spyderco Ultra Fine
3. Degussit Ruby Stone

In order of cost (cheapest first)
1 Spyderco Ultra Fine
2. Translucent Arkansas
3. Degussit Ruby Stone

The Degussit is the fastest, the finest and cleans easier than the Spyderco. Its 100% sinterered ruby. Many will pooh pooh it due to cost, but honestly if you start talking about 15k or 30k water stones which are in the consumables category vs a ruby stone which you will never wear out. You will wear a groove in the Spyderco if you can imagine that long before you will the Ruby stone. In normal use you won't even wear a groove in the Spyderco.

[Patrick Chase]

The Degussit is the fastest, the finest and cleans easier than the Spyderco. Its 100% sinterered ruby. Many will pooh pooh it due to cost, but honestly if you start talking about 15k or 30k water stones which are in the consumables category vs a ruby stone which you will never wear out. You will wear a groove in the Spyderco if you can imagine that long before you will the Ruby stone. In normal use you won't even wear a groove in the Spyderco.

Ruby is simply alumina with an impurity (Chromium) that make it red. Unfortunately for Degussit, that impurity does absolutely nothing for its hardness or abrasive properties. It's Mohs 9, just like bulk Alumina. In other words, it's the same abrasive as in the Spydercos and in most synthetic oil- and waterstones.

IMO the Degussit is mostly unique in terms of marketing and appearance. The notion that any Alumina stone could be used to sharpen carbide as they claim is risible, when you consider that commonly used carbides are quite a bit harder than Alumina (including Ruby).

It sure is pretty, though not several hundred dollars' worth of pretty IMO.

Of the stones you listed the "odd one out" is the Ark. That one is comprised of silicate, which is quite a bit softer, slower, and more limited in the steels that it can handle than either of the Alumina options.

[Stanley Covington]

Ruby is simply alumina with an impurity (Chromium) that make it red. Unfortunately for Degussit, that impurity does absolutely nothing for its hardness or abrasive properties. It's Mohs 9, just like bulk Alumina. In other words, it's the same abrasive as in the Spydercos and in most synthetic oil- and waterstones.

IMO the Degussit is mostly unique in terms of marketing and appearance. The notion that any Alumina stone could be used to sharpen carbide as they claim is risible, when you consider that commonly used carbides are quite a bit harder than Alumina (including Ruby).

It sure is pretty, though not several hundred dollars' worth of pretty IMO.

Of the stones you listed the "odd one out" is the Ark. That one is comprised of silicate, which is quite a bit softer, slower, and more limited in the steels that it can handle than either of the Alumina options.

Thanks for the insight, Patrick. Very enlightening.

Stan

[Warren Mickley]

I have used Arkansas stones for sharpening carving gouges for 40 years. It takes about 25 seconds to hone and strop a gouge. All of the other professional carvers I know use Arkansas stones also. We never grind a carving gouge.

[Philipp Jaindl]

For my oilstone set up when a little more polish is wanted than a translucent Arkansas stone will provide there are a couple of jasper stones on my bench. This can often be found in a lapidary supply store. (gem and mineral supply)

A quick search on jasper stone hones found this:



My two pieces about 2"X5" were less than $20. The ones processed specifically for sharpening will be a bit more. One of the interesting aspects of having a wife who is into gems and minerals is often finding some exotic stones useful for sharpening at found at a yard sale prices.

jtk

hm Jasper does sound interessting, even if its maybe a bit more unorthodox but i dont care as long as it works. Sometimes good tools dont have to be expensive after all.

Ruby is simply alumina with an impurity (Chromium) that make it red. Unfortunately for Degussit, that impurity does absolutely nothing for its hardness or abrasive properties. It's Mohs 9, just like bulk Alumina. In other words, it's the same abrasive as in the Spydercos and in most synthetic oil- and waterstones.

IMO the Degussit is mostly unique in terms of marketing and appearance. The notion that any Alumina stone could be used to sharpen carbide as they claim is risible, when you consider that commonly used carbides are quite a bit harder than Alumina (including Ruby).

It sure is pretty, though not several hundred dollars' worth of pretty IMO.

Of the stones you listed the "odd one out" is the Ark. That one is comprised of silicate, which is quite a bit softer, slower, and more limited in the steels that it can handle than either of the Alumina options.

So i suppose the Spyderco is in the lead for now, just gonna wait a bit longer maybe someone else has some suggestions.

[Patrick Chase]

I have used Arkansas stones for sharpening carving gouges for 40 years. It takes about 25 seconds to hone and strop a gouge. All of the other professional carvers I know use Arkansas stones also. We never grind a carving gouge.

Same here. All of my carving tools are Pfeil, and sharpen very nicely on Arks.

[Pat Barry]

Ruby is simply alumina with an impurity (Chromium) that make it red. Unfortunately for Degussit, that impurity does absolutely nothing for its hardness or abrasive properties. It's Mohs 9, just like bulk Alumina. In other words, it's the same abrasive as in the Spydercos and in most synthetic oil- and waterstones.

IMO the Degussit is mostly unique in terms of marketing and appearance. The notion that any Alumina stone could be used to sharpen carbide as they claim is risible, when you consider that commonly used carbides are quite a bit harder than Alumina (including Ruby).

It sure is pretty, though not several hundred dollars' worth of pretty IMO.

Of the stones you listed the "odd one out" is the Ark. That one is comprised of silicate, which is quite a bit softer, slower, and more limited in the steels that it can handle than either of the Alumina options.

As I recall there are lots of grades of Alumina (ie: 85% pure to 99.8% pure) and correspondingly there are lots of variation in hardness. Commercially available sapphire / ruby are specific grades containing alumina that might be on the higher end of the hardness scale. You'd have to know the sources for both to know for sure what grades they use. I don't know what grades are being used with the Spyderco versus the Degussit examples mentioned but if the Spyderco used 85% pure alumina for example, and the degussit used 99.5% pure alumina there will be a huge difference in hardness.

[Patrick Chase]

As I recall there are lots of grades of Alumina (ie: 85% pure to 99.8% pure) and correspondingly there are lots of variation in hardness. Commercially available sapphire / ruby are specific grades containing alumina that might be on the higher end of the hardness scale. You'd have to know the sources for both to know for sure what grades they use. I don't know what grades are being used with the Spyderco versus the Degussit examples mentioned but if the Spyderco used 85% pure alumina for example, and the degussit used 99.5% pure alumina there will be a huge difference in hardness.

It's easy to tell that isn't the case by color alone. Impurities change the color of Alumina, with Degussit's stones being "exhibit A". They're red because they're doped with Chromium, which does nothing for the material properties.

Spyderco's fine stones are (very obviously) made of white Alumina, which is the highest purity grade used in abrasives (>99%). Ditto for most of the better waterstone makers like Naniwa, Shapton, Imanishi, and Sigma.

[Pat Barry]

It's easy to tell that isn't the case by color alone. Impurities change the color of Alumina, with Degussit's stones being "exhibit A". They're red because they're doped with Chromium, which does nothing for the material properties.

Spyderco's fine stones are (very obviously) made of white Alumina, which is the highest purity grade used in abrasives (>99%). Ditto for most of the better waterstone makers like Naniwa, Shapton, Imanishi, and Sigma.

Sure

How do you KNOW what actual grades of alumina are being used? You can't tell just by color for example because there are lots of grades of whiteness in the alumina if you didn't have some known material to compare to.

[Patrick Chase]

Sure

How do you KNOW what actual grades of alumina are being used? You can't tell just by color for example because there are lots of grades of whiteness in the alumina if you didn't have some known material to compare to.

Yes, but at some point it doesn't matter for a simple abrasive like this. AFAIK all white alumina are >99% purity, and the hardness/toughness differences become very small as you go beyond that IIRC. You're right that we don't know if Spyderco's WA is 99.8% pure or 99.5% pure, though it's likely of higher purity than the Degussit stone :-).