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rbscebu
Girls call me Makaluod
I'm in no rush. Will get around to trying this stone sometime after Christmas.How is the edge? That's all that matters
I'm in no rush. Will get around to trying this stone sometime after Christmas.How is the edge? That's all that matters
I'm in no rush. Will get around to trying this stone sometime after Christmas.
I very much doubt that that will happen. I am now rather put off natural whetstones.
Thank you. You are right. I needed your words to get back on track.I think everyone appreciates predictability in an abrasive. Natural whetstones can frustrate a person that expects a particular scratch pattern from a new natural. The only way naturals work for anyone is if they learn the nature of the stones in front of them.
@ables and @cotedupy helped to adjust my perspective about a particular stone a few months ago. There was a disconnect between what I expected the stone to be and what the stone actually was. I've adopted a much different attitude now, and not just toward that one stone, but towards all of my stones. I no longer expect a particular abrasive behavior out of any of them based solely on a rock's geological identity.
I've been going through all of my stones, one at a time, obtaining a better understanding of what I should expect each one of them to do. I vary the surface prep, pressure, and honing fluid with each rock. Don't even bring up slurries; that can of worms is staying shut for now. My learning rate is slow. There is usually little time during the week for honing and the weekends can be tough for that as well.
There are no grit ratings or labels. There are only abrasion rates and scratch patterns. When I'm done learning about my rocks' abrasive characteristics, the path to a pleasant straight razor shave will be much more predictable.
You've got a new rock and it likely does something very well. It is up to you to discover what that something is and then use that knowledge to your advantage.
I don't believe that I have been stung. I have since learnt that my black Arkansas was originally sourced from RH Preyda in the US through the Australian importer. Genuine black Arkansas whetstones have a SG of generally around 2.6 to 2.75 although some can be higher and others down to almost 2.0. Two gemologists have rated my whetstone as having a Mohs hardness of 6~7 (being closer to 7) and believe it is Novaculite. In their opinions, the stone is definitely not slate.The path to the top of the mountain is not always smooth and predictable. Sometimes you just have to pause, lick your wounds and pull yourself back up by your bootstraps. The good news is that you learned something after being stung by the unknown.
You would be surprised what sic powder on glass or granite (starting out with 80 grit) will save you time and money to get your ark flat and clean. Would not go higher than 1200 grit though. With usage will come finesse.Hopefully, I will only have to lap this black Ark once. It's a lot of hard work for an old(er) man. My current thoughts are to take one side up to a 600 grit W&D finish and the other side up to a 1k or 2k grit W&D finish.
I have an hard black Arkansas which I bought over Ebay Japan, a superb finisher. The whole wrapping of the stone looked very cheap, so I was not sure what I was gonna get. Did finish a couple of razors on it and the shaves were very nice. The SG I measured was more than 3? Question myself if this is even possible? Under my small microscope I noticed some golden pyrite? inclusions. Maybe it is even traces of gold, which could explain the higher SG that I would expect from a black Ark.I don't believe that I have been stung. I have since learnt that my black Arkansas was originally sourced from RH Preyda in the US through the Australian importer. Genuine black Arkansas whetstones have a SG of generally around 2.6 to 2.75 although some can be higher and others down to almost 2.0. Two gemologists have rated my whetstone as having a Mohs hardness of 6~7 (being closer to 7) and believe it is Novaculite. In their opinions, the stone is definitely not slate.
I am very contented with the whetstone I have bought as a black Arkansas. Others here may not believe but that is there problem. I will continue down my path in learning more about this whetstone in my own way.
@Tomo suggest 160 grit SiC powder to me for lapping flat. That was not readily available to me so I settled on 180 grit for lapping my black flat. Fortunately the two surfaces were already reasonable flat so it didn't take too many hours with my 180 powder on a granite slab and sheet of worn W&D.You would be surprised what sic powder on glass or granite (starting out with 80 grit) will save you time and money to get your ark flat and clean. Would not go higher than 1200 grit though. With usage will come finesse.
The case for my black Arkansas is all finished. Western red cedar treated with multiple layers of polished beeswax.
All is now ready to go. The white side has been finished on 1.2k grit W&D while the other side has been finished on 600 grit W&D.
I have two identical Titan ACRM-2 T.H.60 SRs available. They have both been finished and maintained on 0.1μm diamond pasted balsa strops. All bevels currently have a mirror finish. As far as I can tell, they shave identically. One has been marked in black nail polish on the tail and that SR will be used on the black Arkansas.
A well thought out response, probably more than mine, based on the basic evidence.Nice box R, you're good at those eh!
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Just to explain a bit about some things above, as there can be slightly confusing and sometimes contradictory information out there, and might take a long time to wade through. All of what I'm about to say though I can basically guarantee you is true, apart from the final paragraph which is an educated guess.
The stones that people here generally refer to when talking about 'black arks', are a kind of very pure, hard and fine novaculite, extremely similar to translucent arks, but black. And the best of them in terms of razor honing have tended to come from Norton or Dan's. They have SGs from about 2.60 to about 2.70 tops, with most probably falling in the 2.63 - 2.68 range.
It'd be rare, but you could have a black coloured Arkansas novaculite with an SG below that. However it wouldn't be what we tend to call a 'black ark'. Lower SG in Arkansas stones comes from having more porosity in the stone, literally like a microscopic sponge, this is why Washitas absorb oil and people degrease them. More porosity in the stone means it will cut faster, but finish lower. A black coloured Arkansas novaculite with an SG below 2.50 will absolutely not be the level of razor finisher that a 'black ark' will be.
Now your stone has an SG a little higher than 2.70, and it seems to be the kind of black Arkansas stone that Preyda sell, which some people call slates. I've never had one of these stones, but if you asked me to guess what the SG of a novaculite with some slate-like characteristics I'd say it'd probably come in something like 2.72 - 2.75.
Note though that having some slate character does not make it a slate. As David pointed out above: novaculites can have slate-y character. In fact the very first description of novaculite (the term was invented in the late c.18th) mentions their 'slatey and splintery fracture'. This is noticeable particularly in Llyn Idwal stones, which have SGs in the low to mid 2.7s. Whereas true slate honestones tend to go from about 2.77 - 2.90 ish.
Long story short... my guess, which everything so far in this thread seems to support, is that the Preyda Black Arkansas is a novaculite, just perhaps a little less pure, and less tightly bonded at a macro and crypto crystalline level than the black arks from Dan's or Norton. And the difference in effect is likely to be very small indeed, you will still probably be playing at the very upper echelons of how sharp you can make something using a whetstone.
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Anyhow, look forward to hearing the results!
A well thought out response, probably more than mine, based on the basic evidence.
Reminds me of our discussion on my Glanrafon, which seemed to me resembled a novaculite for practical purposes, but apparently is not. But is something close.
Where it gets confusing is there is a huge range of different novaculite. And slate. And at what point do they intertwine and how?