I was wondering if one can use a Zulu Grey (or any other natural stone) the way one uses a Coticule. Meaning diluting the slurry down to plain water just like in a Dilucot. Any ideas?
Diluzulu?
- Thread starter Thomas Martin
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I do it - I just assumed that was the way to use the Zulu Grey. I don't try to bevel set, or even do much to improve bevel, with the Zulu - too hard. My current process (changes as I learn more every day) is to set bevel on King 1K, go to Coticule, light slurry on the Zulu Grey, then a few laps on 0.25 diamond spray on felt, then back to the Zulu adding soapy water (diluting the already skim-mike slurry) with very light strokes until "done". Sounds wierd with the pasted strop, but I get good results!
I do the same thing as Chuck. I will set the bevel on a 1kC, then do a lot of the mid-range work on a coticule. When I am 'most of the way' there, I will raise a slurry on the Zulu & do 30ish x strokes, then dilute, & do 30 more. I will keep diluting until I get down to slurry-tinged water and finish on that....Works very well!
I haven't found diluting slurry on all stones to be consistently beneficial. I got no reward on the Zulu, negative results on welsh slates, and some success on some Eschers.
I get consistently good results on Jnats with diluting slurry though.
The alleged reasoning behind diluting on a Coti might not apply to other stones, but if the technique proves itself after several comparisons then that's that. Gotta test, test, and test again.
I get consistently good results on Jnats with diluting slurry though.
The alleged reasoning behind diluting on a Coti might not apply to other stones, but if the technique proves itself after several comparisons then that's that. Gotta test, test, and test again.
The reason dilution on coticules is a good idea is because the garnets in the slurry do not break down. Jnats thuringians, etc break down.
A lot of people seem to think that slurry's primary purpose is to speed up cutting directly by abrading the edge itself. The use of slurry from every historical text I've ever read references its purpose to increase the rate at which the stone abrades (effectively lapping the stone with the slurry being pushed around by the tool you're honing) and consistently expose fresh abrasive particles. This applies to both naturals and synthetics. Exceptions I'm aware of being Jnat Nagura and of course coticules. The impression given is that in the majority of cases, the abrasion done by the slurry itself is insignificant compared to the abrasion done by the fixed particles because the slurry is simply pushed along before, rather than cutting the edge. Coticules seem to be an exception because their particles tend to only expose and cut with a very small part of their area when fixed to the stones surface. Also I recall some theorizing that the garnets in a coticule slurry tended to become wedged against surfaces of the stones fixed garnets due to their shape, causing the aggressive cutting of a slurried coticule.
So essentially. Yes, the vast majority of stones will cut faster used with slurry... not necessarily for the reasons you think, but they will. Will they perform similarly to your typical coticule? Not really. Yes, you can and people have dilu-thuri'ed and even dilu-norton8k'ed. It works in as much as it doesn't totally not work. But you could also prove that you can hone a razor start to finish on 0.1micron film... if your time really had so little value.
So essentially. Yes, the vast majority of stones will cut faster used with slurry... not necessarily for the reasons you think, but they will. Will they perform similarly to your typical coticule? Not really. Yes, you can and people have dilu-thuri'ed and even dilu-norton8k'ed. It works in as much as it doesn't totally not work. But you could also prove that you can hone a razor start to finish on 0.1micron film... if your time really had so little value.
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That's a most interesting piece if information. Thank you. Would you say that honing an edge on water only on a finisher would further refine an edge as compared to finishing on slurry?
Thuringian slurry breaks down? Has that been confirmed?
Many feel that they do - I am not convinced, but I won't rule it out either.
I don't 'feel' that sensation when using a Thuri - but that isn't a perfect read of what's going on.
I don't 'feel' that sensation when using a Thuri - but that isn't a perfect read of what's going on.
Everything breaks down. Hell, Diamonds in plates break down. The distinctions are how easily they break down. Jnat slurry is famed for breaking down, so I feel it's safe to assume its particles break down quickly. Coticules are known for the garnets not breaking down, so I'd assume they break down slowly enough it has no use as a consideration in honing. Thuringians? They were traditionally used with or without slurry, and with VERY limited passes, so I'd expect any breakdown was not significant enough to be noticed back in the days when they were a very common stone, so I doubt it's significant enough it's viable to adjust technique around it.
Thomas. With some stones it does. With some stones it does not. "Slurry Dulling" is a catch-all term for the damage done to the very edge of the tool (essentially, the abrading slurry does), so in general it would be logical to assume that in the majority of cases it will be true. Of course, with stones that are very hard but with very readily broken down abrasives (for example, very hard and fine jnats), there would seem to be a compromise, as the stones surface abrasives may wear down beyond the point of usefulness faster than the stone exposes new abrasive particles... in cases such as this, finishing on a slurry will cause the stone to finish finer than finishing without slurry. Then of course there is the interest now from the recent SEM images from Fuzzy in the potential of the "dulling" effect of the slurry (they focus on the convexing of the bevel specifically) causing the edge to be more able to sustain a higher level of refinement, so the end result if their opinions are accurate would be that the slurry-finished edge could be finer (The average thickness at a chosen line between the minimum and maximum expanse of the blades depth would be lower on the slurry-finished edge). This would be difficult to argue with certainty one way or the other, even if it is the case, as that measure, while significant to sharpness, is not equivalent to sharpness.
Thomas. With some stones it does. With some stones it does not. "Slurry Dulling" is a catch-all term for the damage done to the very edge of the tool (essentially, the abrading slurry does), so in general it would be logical to assume that in the majority of cases it will be true. Of course, with stones that are very hard but with very readily broken down abrasives (for example, very hard and fine jnats), there would seem to be a compromise, as the stones surface abrasives may wear down beyond the point of usefulness faster than the stone exposes new abrasive particles... in cases such as this, finishing on a slurry will cause the stone to finish finer than finishing without slurry. Then of course there is the interest now from the recent SEM images from Fuzzy in the potential of the "dulling" effect of the slurry (they focus on the convexing of the bevel specifically) causing the edge to be more able to sustain a higher level of refinement, so the end result if their opinions are accurate would be that the slurry-finished edge could be finer (The average thickness at a chosen line between the minimum and maximum expanse of the blades depth would be lower on the slurry-finished edge). This would be difficult to argue with certainty one way or the other, even if it is the case, as that measure, while significant to sharpness, is not equivalent to sharpness.
