Stone collection, next step in usage (and possibly purchases?)

Kitchen Knife Forums

Help Support Kitchen Knife Forums:

Joined
Nov 27, 2016
Messages
345
Reaction score
416
Location
Sweden
This is a long-ish stone multiple part question, partly to gather my own thoughts, but also to get any feedback from you wonderful experienced people. I am an amateur and mainly sharpen my own knife so unless I do something stupid I don’t expect any one stone to be worn out in my lifetime.
The collection below is collected over the past five years or so. This far I have been focusing on edge sharpness and I can now reliably get a good cutting edge with my various knives. My knives are mainly carbon (shirogami, aogami) but the odd stainless (AEB-L, VG-10) is also in the collection, as are some cheaper stainless beater knives (IKEA FTW!)

Now I want to dive into your experiences with what I have and possibly if something could be handled differently as I also am planning to try thinning and polishing knives. People have said that sharpening is 90% technique and 10% equipment and the more I grind, the more I tend to agree with this. Therefore I really want to get the most out of the stuff I have before buying more. On the other hand, buying is fun :)

Current inventory:

Atoma 140, 400
Shapton Glass 500, 2000, 4000, 6000 (last one is HC, the others HR versions)
Naniwa Pro 600, 1000, 2000, 3000
JNS Matukusuyama 300 (current version), 800, and synthetic Aoto (blue speckles).
JKI Gesshin 6000 speckled blue.
And a natural, an Aiiwatani (number three in this ad)

(and some strops too, of course)

(jeepers, how did I get so many?)


Stone care:

My JKI Gesshin 6000 has been soaked and dried by the previous owner, now sealed and mounted on base after that owner discovered small cracks, and it is since then used as splash & go. From the JKI website: “The Gesshin 6000 splash and go stone is a resinoid based stone with a white alumina oxide abrasive”. Either permasoak or splash & go. I guess this is still a smart thing to do - to not soak any more?

All other stones were purchased new or in new-like condition and are used only as splash & go with the obvious exception of the JSN 800 which I currently permasoak.

Especially for the Naniwas and the JNS Synthetic Aoto, my understanding is that I will not gain anything by soaking, better kept as splash & go. Correct? Is there any use in sealing and/or mounting either of these stones on a base?

Next steps - thinning and polishing

Efter learning to get the cutting edge right, the next step is obviously thinning and then getting the finish/polishing right. I’m thinking here of both kasumi and more mirror-like polishing eventually. I have gathered up a long list of threads here and youtube videos on the subject that I’m going through, but everyone has their own favorite stones… and as I said, I’d like to start with what I have if possible.

Do you have any direct recommendations for stone use here - should I be good to go with what I have, or is there a recommendation for e.g. different coarse stones to start thinning? I have tried some “relief bevels” on the stainless beaters using the Atomas, but I’m a bit scared to put good knives on these kind of coarse diamond stones.

In other threads, I’ve read Dave Martells praise of the King 800 for starting kasumi finishing but he also mentioned that the JNS 800 can do a good job?

At some point I guess I also need to look at sand papers and finger stones… but that’s probably a bit later in the game. :)

That was a long posting, and any feedback to my ponderings is appreciated. :)
 

Lars

Founding Member
Joined
Mar 9, 2011
Messages
2,450
Reaction score
11,548
Location
Denmark
I soak my JNS synthetic Aoto and love the way it feels. It's my finishing stone roughly 96,87% of the time..
 

Benuser

from The Netherlands, EU.
KKF Supporting Member
Joined
May 3, 2011
Messages
8,253
Reaction score
2,949
You probably may start your first thinning with the SG500. Proceed by little steps. Any sharpening at a lower angle than the one you use for the very edge, is thinning. A first goal may be to easen or remove the shoulders — where bevel and face meet. A next step is going on at that same angle until you've almost reached the very edge, and the bevel is reduced to a hairline. A permanent marker and a loupe — 10x perhaps — are very helpful to show where you're actually abrading steel. Later on you may go further and remove more thickness behind the edge. A few figures to give an idea of what you could aim for: a general purpose knife as a chef's or a gyuto, which encounters a lot of board contact, can safely be thinned up to 0.2mm behind the bevel, and 0.5mm at 5mm upward. At 10mm a thickness of 1mm is a good value, but thinning there isn't the first thing you will be doing.
For maintenance thinning, the SG320 is an excellent stone. It provides even some tactile feedback, which isn't that evident with such coarse a grit. For larger thinning projects, even coarser grits are available, as the SG220, SG120 and the Norton Crystolon. We will discuss it in another thread. For now, if you were to use very coarse stones, make sure to stay away from the edge. And don't use your Atomas for thinning, as they leave deep grooves and are likely to get damaged themselves.
Once you have a knife with the geometry you like, let thinning be a part of the sharpening routine.
 

tcmx3

Senior Member
Joined
Feb 5, 2015
Messages
1,954
Reaction score
2,540
yeah I agree dont use the Atomas to thin.

from my perspective Id say a Suehiro debado 180 grit stone or some other course sub 200 grit stone would probably be a good investment.

you say it's 90% technique, well yes and no. it is ABSOLUTELY true that if you dont make good shaped bevels (technique) you are unlikely to ever get good results. so you must do that first. for final polish though I find that it's mostly about the stone, again assuming you've made your bevels well shaped.

I will be honest the number of knives Ive gotten that could go on a SG500 out of the box is quite low. you could try though.
 

tcmx3

Senior Member
Joined
Feb 5, 2015
Messages
1,954
Reaction score
2,540
Thanks @tcmx3



I'm sorry, I didn't really understand that bit. Can you please elaborate what you mean?


SG500 is quite hard, especially for it's grit. so you will only hit the high spots on most bevels because they aren't as consistent as their finishes make them look. and because it's not really that coarse, grinding the high spots down to make an even bevel will takes you AGES.

IMO it's better to use some <200 grit stone and like a 300-400 THEN you use SG500. if you have done a good job prepping the bevels SG500 is amazing and if your knife comes off it looking good the chances you can make a good final finish are very high.

if you can find the time, I would watch this whole video from Milan Gravier:
 
Joined
Nov 27, 2016
Messages
345
Reaction score
416
Location
Sweden
Thank you @Benuser and @tcmx3 for your elaborate replies. I have much studying to do, and probably even more practicing. :)

Benuser, you mention Shapton Glass stones in the lower ranges. I do have the JNS 300 - do you think this stone has a place here?
 
Joined
Nov 27, 2016
Messages
345
Reaction score
416
Location
Sweden
I soak my JNS synthetic Aoto and love the way it feels. It's my finishing stone roughly 96,87% of the time..

Lars, two questions:

- How much do you soak it, and how careful must one be to try it? On the JNS web page is says that it is best used as a splash & go?

- When you say finishing, to you mean final stone on the edge or finish as in polish the side of the blade?
 

Lars

Founding Member
Joined
Mar 9, 2011
Messages
2,450
Reaction score
11,548
Location
Denmark
Lars, two questions:

- How much do you soak it, and how careful must one be to try it? On the JNS web page is says that it is best used as a splash & go?

- When you say finishing, to you mean final stone on the edge or finish as in polish the side of the blade?
I permasoak all my stones. It's never given me any problems.

As the final stone on the edge.
 

Lars

Founding Member
Joined
Mar 9, 2011
Messages
2,450
Reaction score
11,548
Location
Denmark
Do we know how the JNS Synthetic Aoto (blue speckles) reacts to soaking in this aspect?
It's a resinoid stone so no problem. Just dry it slowly in case you don't want to store it in water.
 

tcmx3

Senior Member
Joined
Feb 5, 2015
Messages
1,954
Reaction score
2,540
Saw this video last night and remembered this thread...



No firsthand experience but thought it was worth sharing.


I was going to buy some to try it out but unfortunately shipping to the US cost more than the vial itself and I already have big chunks of uchi around I can just grind up.
 
Joined
Nov 27, 2016
Messages
345
Reaction score
416
Location
Sweden
Well... in addition to the sharpening pics I posted in the other thread I actually made my first attempt at grinding above the edge on a cheap knife now using the same stones as in the other (JNS 300, 800, blue synt aoto)... looked... not good. And made not much difference in profile. But I got a screaming sharp edge at least. :)

As I did this on a really cheap massmade knife (Kanetsune KC 331 if memory serves me right) with stainless cladding over carbon core I'm not sure how representative this is.. but at least I started getting some finger feel for this process.

Result so far, first grinding above the edge, and then sharpening the edge:

DSC_0519.JPG

DSC_0518.JPG


When I look at the knife grind, it looks like the left hand side (with logo) is much flatter thus creating a high line of core steel exposed, while the right hand side has cladding going much closer to the edge, and then a high angle for the actuall grind of the cutting edge. This MAY have been caused by my initial sharpening lessons five years ago. :)

Hard to take a coil shot with my phone but perhaps it explains more what I mean:

DSC_0520.JPG


It was fun seeing the cladding getting different between the stones. After the 800 stone, it got really dark, then lighter grey again after the aoto.

Thank you all for input, now I have much more to go on. And much grinding to do.
 
Top