Am I thinning it right?

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Briochy

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I'm thinning my 240mm Watanabe Carbon gyuto. However, I'm pretty new to thinning. From this picture, can you tell me if I'm doing it right? I basically just try to lay it on the 'shinogi' plane of the knife (although not a well-defined one) and I just go up and down the blade. The 'shinogi' on this knife doesn't seem to be straight.
 

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The way I'm seeing the scratches in your photo, most of the thinning seems to be going on higher up the blade face. I'm not seeing many scratches right near the edge.
Give the marker trick a try. This'll help you see where your scratches are.
There's more than one type of thinning, too... (1) Thinning behind the edge and (2) general thinning.
(1) You'll want to remove metal from as close to the edge as possible, as this is where the edge gets thicker over time due to repeated sharpenings. Think of this like maintenance thinning. Keep the spine off the stone.
(2) This said, there's also nothing wrong going for much more aggressive: thinning--removing metal from behind the edge all the way up half (or two thirds) of the blade face, if you're trying to thin the knife out more in general. Basically lay the knife flat (or close to it) and see what's happening.

Regardless of what you're after, more scratches would help :)

This shows (1) Thinning behind the edge and (2) general thinning. Red lines help show angles.
thinning.jpg
 
The way I'm seeing the scratches in your photo, most of the thinning seems to be going on higher up the blade face. I'm not seeing many scratches right near the edge.
Give the marker trick a try. This'll help you see where your scratches are.
There's more than one type of thinning, too... (1) Thinning behind the edge and (2) general thinning.
(1) You'll want to remove metal from as close to the edge as possible, as this is where the edge gets thicker over time due to repeated sharpenings. Think of this like maintenance thinning. Keep the spine off the stone.
(2) This said, there's also nothing wrong going for much more aggressive: thinning--removing metal from behind the edge all the way up half (or two thirds) of the blade face, if you're trying to thin the knife out more in general. Basically lay the knife flat (or close to it) and see what's happening.

Regardless of what you're after, more scratches would help :)

This shows (1) Thinning behind the edge and (2) general thinning. Red lines help show angles.
thinning.jpg
Yes, my plan is to do the former followed by the latter. I just found that the area that's touching the stone is kinda uneven, that's why I'm asking. And about sharpie, I was planning to use it in the latter stage where scratch wouldn't tell me anything anymore.
 
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Yes, my plan ia to do the former followed by the latter. I just found that the area that's touching the stone is kinda uneven, that's why I'm asking. And about sharpie, I was planning to use it in the latter stage where scratch wouldn't tell me anything anymore.
Judging from the picture, basically I think waaaaaay more scratches would help :)

I like the marker trick when thinning because it helps you check finger placement/pressure when starting. Even though the knife is flat on the stone, finger placement/pressure can still make a noticeable difference.

See if you can find @stringer thread(s) on thinning. He's done several really helpful threads on thinning and with photos of progress.
 
There's also a really good chance to ruin the nice convex grind like this, especislly if you are inexperienced.
 
There's also a really good chance to ruin the nice convex grind like this, especislly if you are inexperienced.
Yeah I agree I might have, but I don't really know. It's now pretty thin behind the edge, but still kinda hesitates on the potato a lil bit (I guess that's partly due to it being a WH). Still need to polish it though
 

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Your thinning it wonderfully. (In my opionion)
Your hitting Cladding steel throughout blade, just make sure to put more pressure on the core steel. It abrades slower than the cladding. -- the whole goal is to raise that cladding line.

There are a few ways to go about this thinning.

Thinning directly behind the edge, Really (to me) though you are just sharpening at an extremely steep angle. ( i consider this thickening of the knife)
Thinning the core steel only -- basically what your doing with pressure purely on the core steel.
Thinning the knife ... laying that sucker flat and turning into what looks like a Fujiyama. Raise that Shinogi line - raise that cladding line.

After that, use the blade, then repeat the thinning untill your happy. once you can go a few sharpenings with your thinned blade, use sand paper to give a nice even finish... 400-1000k i would recommend. Give it its first sharpening (sand paper kills the edge) --- and presto its new knife day yet again.
 
Thanks, a lot. I love your work on Shig Santoku too, that was pure amazing

Thanks, can’t truly learn until you do it, right? I am still not done, the mouse Beveler sets a nice clean border but it became a horizontal line once I am done with the stones. Going back to thin it further & raise the shinogi line again for a more natural transition to KU.

It’s still not as sharp cut as I wanted. Darn it, for a moral victory, I need the Shig. Funayuki to beat Kurosaki.
 
You got a nice finish on there now, how is it feeling?
FYI the handle is just on with wax so you can knock it off if it gets in the way.
Food penetration feels great now. I think I haven't compromised the food release, which is good. The only flaw now is that the balance is too forward. Given it's already a heavy WH blade, I don't feel like it needs to be that (5 cm from the handle) blade heavy. The handle lacks taper + too small for my hand. After I do a quick run to KnS for a new handle, it'll be a perfect knife for me. Also, likely a forever keeper. ;););) Next station: Patinaland
 
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