Resources and stones to move past sharpening

[hainew]

Hello all,

I've promised myself that before I spend any more money on knives, I will lift my game in terms of maintaining them. I'm happy with the performance of my edges, but am looking for resources on moving past just sharpening the edge, into flattening the blade road, polishing, adjusting edge geometry, etc.

My project knife is a Teruyasu Fujiwara Nashiji Gyuto. As many of you know, the fit and finish on these knives leave something to be desired. Early attempts to polish have revealed definite highs and lows in the grind. But some of the visual effect is probably also just my crap polishing technique. So I'm hoping to be able to flatten it with confidence, so I know I've succeeded, and thus know what's the result of my polishing technique. Ultimately aiming to be able to both reproduce the factory finish, and create a reasonable kasumi with a strong contrast. But despite the wealth of information about technique for sharpening the edge, I've found virtually nothing laying out actual technique for doing these things.

I'm also pretty sure I'll need new stones. I currently use an AI1000 (which is just a Shapton pro, and cuts more like an 800 in reality), then an Arashiyama 6000, then a relatively cheap Yaginoshima Suita. The Suita leaves a high contrast kasumi finish, but the other stones don't lay a good foundation for it. I'm thinking to replace them with a JNS 800 and JNS red synth aoto, but would really welcome all suggestions. Maybe the Morihei Hishiboshi 1000 and 4000 instead?

Where would you guys read/watch up and what stones would you turn to in my position?

 

[bsfsu]

Maybe add in a couple of stones between the 1000 and 6000 tO smooth the progression?

 

[besserbissen]

The Suita leaves a high contrast kasumi finish, but the other stones don't lay a good foundation for it. I'm thinking to replace them with a JNS 800 and JNS red synth aoto, but would really welcome all suggestions. Maybe the Morihei Hishiboshi 1000 and 4000 instead?

If you want to flattening the blade, I would start with much coarser grindstones. I use Atoma 140 and 400 for thinning. Then Naniwa pro 800 or Shapton 1000 to remove the coarse scratches.
Kasumi is not my business, others know JNats much better than I do
BTW: I finish the blade with sandpaper ;-)

 

[bsfsu]

I think @besserbissen is right with the lower grit suggestion.

 

[Kawa]

Your goal is ambitious. Nothing wront with that. I even encourage it. But simply put, you are saying: I want to become very very good at knive polishing.
Don't think you will get there by buying a few new stones. It needs lots of practise. You need to get a feeling of grinding and polishing, working with the right pressure, mud, paste. Knowing how different steels feels on all of your stones.

It's a new journey. You need to learn and practise a lot. So to say, you stop buying new knives before you master this, seems a bit strange. Those are 2 different things in life. A nice kasumi has nothing to do with thinning/maintaining your knive.

Having said that. Getting a good end results gets decided by the ability to remove the scratches from the previous stones. So you need a whole lot of steps.
Your 6000 will never remove the 1000 scratches.
Neither will your 1000 ever flatten the high and low spots.

It's up to you to decide which stones you want to try out. I suggest you start in the 100-200 range. Or even better: start with 80-140 gritt sandpaper for the initial grinding.
After that you want something like 200->400->700->1000->1500->2000->3000->4000->6000->8000->
The gaps get bigger the further you go. And don't let the stone number fool you. Some 6000 stones are actually 4000 or 8000. I'm talking actuel gritt in my example. 3M sandpaper is king for that. Widely available up tp 2500.

 

[hainew]

Sorry @besserbissen, I should have clarified I do also have a 400 grit diamon plate I use to flatten the other plates, so I have that available for thinning also.​

In your lovely photos, I see that initially you have a scratch pattern running orthogonal to the edge along the blade road, and at 45 degrees closer to the bevel. Then in the second photo the scratch pattern runs parallel to the edge. Is this sort of thing purely a matter of preference? When thinning with the diamond plate should I aim for anything in particular?​

 

[hainew]

It's a new journey. You need to learn and practise a lot. So to say, you stop buying new knives before you master this, seems a bit strange. Those are 2 different things in life. A nice kasumi has nothing to do with thinning/maintaining your knive.

They are indeed different things, but i want to get good at them both Seems like in terms of polishing everyone so far agrees smaller grit steps will be necessary. Thanks

 

[Kawa]

What helps remove the previous scratches, flip the direction when you go to the next grit.
So start north/south and the next grit you do east/west.

Make sure you finish in the direction you want.

Also beware that both directions give you different results. For example, when your direction is spine/edge (in contrast of heel to tip), you will round off your primary bevel somewhat (if there is one) or convex the transition area somewhat more.

The main thing to keep in mind, you grind the most where you put your fingers, but also in which direction you put pressure to with those fingers.

 

[riba]

https://youtube.com/@milangraviercoutelier6162

 

[besserbissen]

In your lovely photos, I see that initially you have a scratch pattern running orthogonal to the edge along the blade road, and at 45 degrees closer to the bevel. Then in the second photo the scratch pattern runs parallel to the edge. Is this sort of thing purely a matter of preference?

Picture 1 shows the process of thinning with the Atoma 140 and 400, resulting in the 45 degree scratches.

The 2nd picture shows the intermediate state of the sandpaper finish by hand. I start with grit 80 and go up to 400. The picture shows the status at grit 240.

 

[hainew]

What helps remove the previous scratches, flip the direction when you go to the next grit.
So start north/south and the next grit you do east/west.

Make sure you finish in the direction you want.

Also beware that both directions give you different results. For example, when your direction is spine/edge (in contrast of heel to tip), you will round off your primary bevel somewhat (if there is one) or convex the transition area somewhat more.

The main thing to keep in mind, you grind the most where you put your fingers, but also in which direction you put pressure to with those fingers.

Thank you! That makes perfect sense.

 

[hainew]

https://youtube.com/@milangraviercoutelier6162

This is gold, thank you.