JNats for the budget conscious beginner

**Seraphim** · 08-03-2012, 02:18 PM

That being said, I have theorized many a time that the whole reason guys dig Jnat edges and coticle edges is simply because they are not ultra-refined. A slightly larger grit size than the 0.1um will not refine the edge to such a degree that is will lack self-support. I find a pretty good stopping point for me is about 1um.

The typical "hazy" finish of a Jnat itself would seem to indicate a >1um or so particle size is grinding around on there. And so it will abrade off that last hairy bit of the edge. I prefer to do that via a pasted strop, but the end result may be more similar than not.

**SliceOfLife** · 08-03-2012, 02:42 PM

After shave post strop?

Also, those "After" pics aren't any different to my eyes, except light angle. One has light reflecting at the lense off the teeth, the other (your stropped) has it diffracted (Or more appropriately reflected away from the lense). It's really just playing with angles. Your "damaged" edge has white points on the edge. The "A-ok" has Black points that are still different enough from the background to tell it's edge, not background". Just a matter of where the material is directing light.

And your theory doesn't mesh with my jnat. My jnat produces razor fine edges no different from your 0.1micron at 400x. Coticules you could be right at... of course that's third person here. I find them a bit on the dull side of things. If your theory is true, the only way forward honing would abrade that "hairy bit" is through cutting it back which would leave a toothy edge. You can't argue that they recess an edge through convexing the bevel the way a flexible substrate does. Now there may not be a lot of Jnat edge images out there, but there are enough you should have no problem proving to yourself the edge isn't toothy.

**Seraphim** · 08-03-2012, 02:55 PM

I can't argue Jnat edges, as I don't have one to analyze.

I was trying to reply to your assertion:

I don't think anyone feels pastes improve on a really quality edge

Personally, I think pastes, properly used can definitely improve an edge. YMMV

**SliceOfLife** · 08-03-2012, 03:00 PM

An edge refined to let's say the same grit as the paste? For instance your opinion of shaptons or any other high grit stone in and of itself aside. Do you feel an edge refined without user error, on a whetstone or flat surface impregnated with abrasive particles of any sort @ say 0.5micron would be improved by following that finish with a loaded linen strop with 0.5micron charge?

**Seraphim** · 08-03-2012, 03:08 PM

Originally Posted by SliceOfLife

An edge refined to let's say the same grit as the paste? For instance your opinion of shaptons or any other high grit stone in and of itself aside. Do you feel an edge refined without user error, on a whetstone or flat surface impregnated with abrasive particles of any sort @ say 0.5micron would be improved by following that finish with a loaded linen strop with 0.5micron charge?

Yes, I think so.

I haven't done extensive testing in that regard though. Perhaps I will!

**Kentos** · 08-03-2012, 03:20 PM

I will say the abrasive used makes a big difference. Also the supposed convexing of the edge when using a hanging strop and abrasives adds a lot too.

Someone needs to figure how small the tomonagura slurry breaks down as a razor is honed. I wouldn't be surprised if it is smaller than 1 micron. .05 CBN on a Jnat gives a mirror polish to both the bevel and somewhat to the stone, so I am suspecting the actual grit of a Jnat could be small.

**SliceOfLife** · 08-03-2012, 03:23 PM

I'd love to see it. I myself am a bit biased against convex edges in razors. The difference in cutting ability is quite apparent on a larger scale (knives), and while convex edges have their uses (boning knives, though since it's so much easier I usually triple bevel rather than truely Convex), I myself find a convexed chefs not only immediately recognizable upon use, but rather difficult to work with (A thick spine convexed chefs is MASSIVELY duller feeling). Seeing these properties at that scale I dislike the prospect of shrinking it down to my daily shave. However, given a sufficiently refined edge, no doubt it can be overcome, but then it becomes an issue of does the increased refinement outweigh the durability gain from convexing. Really gets back to preference at that point. I have yet to refine an edge sufficiently to where I found any issue in edge durability. And I am rather certain I have a fairly large breadth of edges at the top end of what I use where detecting an increase or decrease in cutting power is out of my capability.

Coming from that, I wonder if perhaps I should adapt my claim to the idea that you won't find any high end stone users who feel that pastes are necessary. Because I somewhat suspect your interest in achieving the thinnest (and most consistently so) edge possible (Correct me if I'm wrong but it seems that's the reasoning behind films use) may be more served by increased durability from a convex bevel, as the bevel angle falls out of the realm of what you monitor and indeed at these levels quite likely is undetectable.

Of course, no doubt if I did that, the one fellow with a $4000 Jnat who wipes its edge out on chromox would show up to tell me how wrong I am.

In the end, I still would sooner finish a razor on a 16k Shap or 1micron film and clean strop versus going from the previous stone to a 1micron impreg strop. And that's based on the mechanics of each sharpening method giving me an edge that I am positive cuts better through the first method than through the second, and I would have no doubts about the durability of either edge. Someone who approaches it another way would see it as being certain that the pasted strop gives him an edge he's positive is more durable and he has no doubts about the sharpness of either edge. So in the end it's perhaps moot.

**Kentos** · 08-03-2012, 03:50 PM

I followed Iwasaki's paper on Jnat honing, where after the tomo slurry he does a few laps on cromoxed wool felt, then does parallel mini laps on water.

I don't like felt, so I instead do 5-10 laps on .1 and .05 on hanging leather, and skip laps on water. After stropping on clean leather I get HHT root in and I don't see any difference in edge longevity. TBO the .1 and smaller sprays are so small they polish more than cut, so it may not be convexing the edge very much at all. I really have no idea what is going on at the edge, and only know I get smooth almost too sharp edges in this way.

**Proinsias** · 08-03-2012, 05:58 PM

Slice: I'm rather new to the knife sharpening world but a convex edge feeling MASSIVELY duller than a v-bevel would to me be more an indication that my convex edge skills were a bit shit and from what I gather if I'm free handing knife sharpening then I'm gonna end up with a convex edge unless I'm the terminator. Perhaps more degree of convex edge is the issue on razors, if you've established a V bevel at a high grit is little bit of convex likely to make a difference at 30k+?

**linguist** · 08-03-2012, 06:29 PM

Kent i hone on my coticules and get HHT4-5 root in easily. so many honers agree that jnats are finer. somebody should improve the tests and add HHT-6-7-8 maybe :)

**Drybonz** · 08-03-2012, 07:04 PM

Originally Posted by linguist

Kent i hone on my coticules and get HHT4-5 root in easily. so many honers agree that jnats are finer. somebody should improve the tests and add HHT-6-7-8 maybe :)

HHT8 would be you hold up the razor and the hair runs away screaming.

**Woodash** · 08-03-2012, 08:37 PM

Originally Posted by Kentos

I will say the abrasive used makes a big difference. Also the supposed convexing of the edge when using a hanging strop and abrasives adds a lot too.

Someone needs to figure how small the tomonagura slurry breaks down as a razor is honed. I wouldn't be surprised if it is smaller than 1 micron. .05 CBN on a Jnat gives a mirror polish to both the bevel and somewhat to the stone, so I am suspecting the actual grit of a Jnat could be small.

It is. On balance, the particles in Jnat finishers are <1-2 u before any breakdown occurs.

**Kentos** · 08-03-2012, 08:41 PM

After it pops root in its hard to go any further IMO.

You coticule guys with root-in pops have saw tooth edges :(

Just Kiddin!!

**Gamma** · 08-03-2012, 08:47 PM

Interesting - I was under the impression that the abrasive particles in Jnats were 2-3 microns.

**linguist** · 08-04-2012, 02:53 AM

if jnats also have novaculite particules as abrassive material -like arkis,thuris, CF, cretans- then as i know novaculite is 2-3 micron, which defines the cutting properties as the finer is the density.

**Puerco** · 08-04-2012, 03:18 AM

You all talk too much about microns en theoretical stuff, I'd rather look at what happens when I put the blade to my face. For me it comes down to this:

JNAT: incredibly sharp and very smooth, you have to be very careful with a blade this sharp but in experienced hand this gives a very smooth and close shave, great for though beards and sensitive skin. Honing on a JNAT is a zen like experience.

Coticule: this gives the smoothest most forgiving edge of them all, even though the blade is very sharp it feels like shaving with a butter knife. It's hard to cut yourself with a coticule edge, almost as if the blade knows the difference between skin and stubble. Finishing on oil kicks it up a notch. Great for light/medium beards and very sensitive skin and also great for gents who recently made the transition to straight shaving, very forgiving. Like JNATs it's nice to finish a razor in the old traditional way.

Synthetic: They are easy and fast to hone on and give a very sharp edge that's more polished then naturals but it's not my favorite as it lacks that special feeling only naturals give, call it mojo or whatever but it will cut through anything. Great if you have to hone a lot of razors fast or followed by a natural finisher.
I never tried those completely mojo-less films but I think it will be more or less the same.

Cnat: Somewhere between a Coticule and a JNAT, somewhat sharper then a coti and still very smooth, nice finisher for a low price.

Pasted strop/convex bevel: (crox) Although it can be sharp, smooth and forgiving it doesn't give me that feeling only a freshly honed blade does. I think it's forgiving because the round part of the bevel rides on the skin with the edge touching the skin in the same way it touched the strop when it was sharpened, some may like it but personally I don't as I rather have that feeling of a freshly honed straight edge on my face and this just doesn't do it for me.

Now this is all just my opinion based on my experiences and preferences, your mileage may and will vary.

**paco664** · 08-04-2012, 03:24 AM

i must say i only have one synthetic left.... i use it for bevel setting......

say what you want about norton 4k8k .... i found the one i had to be a pain in the ass to keep lapped... and the edges while sharp were harsh and unpleasant to shave with...

**Puerco** · 08-04-2012, 04:33 AM

Yes, harsh is a good way to describe it, synthetics have their use as it is easy and fast to get a sharp edge but I would always follow it with a natural. I found that as little as 30 X strokes on a Coticule with water (or better yet, oil) will tame the harshness considerably without losing sharpness, much faster and easier then doing the whole dilucot procedure (which I still prefer).
My bevel setter is also a synthetic chosera 1K, fast, easy and accurate and followed by a whole progression of other stones so it doesn't matter much what the bevel was set on as long as it's done well.

**paco664** · 08-04-2012, 04:44 AM

Originally Posted by Puerco

Yes, harsh is a good way to describe it, synthetics have their use as it is easy and fast to get a sharp edge but I would always follow it with a natural. I found that as little as 30 X strokes on a Coticule with water (or better yet, oil) will tame the harshness considerably without losing sharpness, much faster and easier then doing the whole dilucot procedure (which I still prefer).
My bevel setter is also a synthetic chosera 1K, fast, easy and accurate and followed by a whole progression of other stones so it doesn't matter much what the bevel was set on as long as it's done well.

another thing that drives me up the wall......

the ONLY stone that matters in a progression is the LAST STONE that touched the edge....

it doesn't matter if the bevel was set with a chosera or a king or a 2$ harbor freight special.... as long as the bevel is truly set and even....

once someone progresses to the next stone then anything done prior doesn't matter....

if someone sets bevel then goes to a coti then finishes on a JNAT... it is a JNAT edge they will shave with... if they finish on a thuri... its a thuri edge... arkie = arkie... etc ad nauseum....

i personally set bevels with a 1k king water stone.... cheap... effective... cheap...My bevel setter is also a synthetic chosera 1K, fast, easy and accurate and followed by a whole progression of other stones so it doesn't matter much what the bevel was set on as long as it's done well
then..
i use a coticule and take it as far as i can with the coti... sometimes i use oil... sometimes i use diamond spray.... sometimes i stop there and shave with it...

but...

sometimes i finish on a JNAT or welsh slate or surgical black or translucent or or or or or...

/rant *(sorry.. its double shift saturday and i am a bit grumpy)

**Gamma** · 08-04-2012, 06:28 AM

Originally Posted by linguist

if jnats also have novaculite particules as abrassive material -like arkis,thuris, CF, cretans- then as i know novaculite is 2-3 micron, which defines the cutting properties as the finer is the density.

Average particle size of abrasive particles in an Arkansas stone is 10 micron.

Jnats from Kyoto also have quartz silica particles, but those stones are not novaculites.

Originally Posted by paco664

the ONLY stone that matters in a progression is the LAST STONE that touched the edge....

Not in my experience. What I've found is that an edge is the sum of its progression, and while a specific finisher will change the edge significantly, that finisher does not have the same end result when different stones are used before it.