First thinning and polishing project. Mazaki 240 Gyuto

[user 50275]

I'm a bit intimidated but hey you gotta start somewhere.

Trying to convex that thing. Gotta borrow a digital cantilever to measure thickness at different heights.

Progression I have in mind:

Random SiC block (feels like 200 at max)
The next jump will be painful to Chosera 1k or Aoto got nothing in between.
Aizu/naniwa Hayabusa
Naniwa SS 10k
Finally try to kasumi on an uchigumori.

Wish me luck

 

[Cliff]

Consider something like SG500 or Chosera 400 in between. That is a big jump.

 

[user 50275]

Handle is off. Let's go.

 

[user 50275]

Hello wavy shinogi my old friend..
I have come to buy new hands

I'm thinking about cheating a straight shinogi line with polish. Was insanely wavey at the start. Now I'm somewhat happy. My hand hurts thinking there is one more side to go

 

[ethompson]

Controlling shinogi placement on gyuto is exceedingly challenging and often not possible. Embrace the wave or use a method like your tape for cosmetics.

 

[Choppin]

love these threads, watching

just some thoughts:

- you could use sandpaper to erase the 200 grit scratches. for convex grinds I often use a SG220 to shape the knife and after that only sandpaper to refinish

- one way to approach the shinogi issue: erase it. like people do with Heijis, just blend it with the blade face. you’ll change the looks of the knife but will gain extra convexity and possibly less wedging

 

[Pie]

Yeah. Yeah the shinogi on my maz post thinning is crazy.

Looks like you’re doing a better job than me tho!

 

[Nemo]

I'm a bit intimidated but hey you gotta start somewhere.

View attachment 227690

Trying to convex that thing. Gotta borrow a digital cantilever to measure thickness at different heights.

Progression I have in mind:

Random SiC block (feels like 200 at max)
The next jump will be painful to Chosera 1k or Aoto got nothing in between.
Aizu/naniwa Hayabusa
Naniwa SS 10k
Finally try to kasumi on an uchigumori.

Wish me luck

Are you saying that it is a flat grind that you are trying to make convex or are you maintaining an already convex grind?

If the former, I wish you luck and will watch with interest. It's a pretty big undertaking.

If you just want to refine your finish before moving to your Chosera 1k, you could use a sandpaper progression. Say, 240, 400, 600 +/- 1000 grit. Use wet and dry (automotive) sandpaper. Use it wet.

Obviously be super careful not to cut yourself doing this. When I do this, I blunten the edge by breadknifing gently on a fine stone.

 

[user 50275]

Gonna go widebevel.
No idea how to convex things.
Grind was flat from the start.

This is the current status

Needs work at the tip.
Jesus the second side was horrible to move the shinogi up. Took me 2.5h
Never gonna thin with my current setup again .

Looks like I'm done in another 2hours and there should be no low spots left.

The good so far:
Concrete pavement on the balcony to flatten and refresh the SiC stone!

Learning to increase the angle at the heel to move the first shinogi wave up. (Probably the taper)

To do:
-) Finish everything with even scratches.
-) Round the coil.
-) Grab a 400 grit stone on Monday.
-) Make some uchi Fingerstones.
-) Ice fingers for regeneration

 

[user 50275]

Time for round 3

 

[user 50275]

Sure there is more to be done but I think for me it's good enough.

SiC

 

[user 50275]

Did a quick run on the 1k and Aoto.
How do I remove this oxidized part right at the shinogi?
Sandpaper?

 

[user 50275]

Time for sleep:

 

[user 50275]

Need to go back to sandpaper to get all scratches out but wanted to work on my stone polishing skills.
This is after a greenish Aoto.
Time to clean the kitchen.

This is where I'm at:

 

[user 50275]

This is where it's at. Front scratches need to be removed. Tried some Uchi + Uchi Fingerstones and faked the wavey shinogi.
Second side is still a mess

 

[mozg31337]

Wow, what a progress! Good luck with it!

Reminds me that I need to finish thinning my wife's Shun Classic Gyuto. I've done one side with 80grit sandpaper and it took me a long time. Need to do the other side before moving onto higher grits.

 

[M1k3]

Wow, what a progress! Good luck with it!

Reminds me that I need to finish thinning my wife's Shun Classic Gyuto. I've done one side with 80grit sandpaper and it took me a long time. Need to do the other side before moving onto higher grits.

Shapton Pro 120 works great on Shun's cladding.

 

[user 50275]

Under natural light:

Will continue this evening!
Getting closer.
The shinogi line is only faked at the end where I messed it up due to taper. Not raising the shinogi at the back seems like a very hard thing to do!

 

[jaydee]

Very cool work!

 

[user 50275]

Project closed

Lessons learned:

-) Is it always so painful to remove metal?
- Maybe I need new low grit stones
-) SiC stones can really scratch deep
-) Sandpapering the scratches out saves lots of time
-) tested some convex grind moves on Aoto and am now confident for a new project to try this
-) First time when flipping the blade mirroring the movements.
Usually when I sharpen I always keep the handle in the right hand.
-) Uchi finger stones makes everything much easier.
-) Polishing ceiling is so much higher but I'd really rather test the grind

 

[user 50275]

Classic case of left at 90% .
Back side is meh. Did a first cutting Test. Looking forward to cooking!
Will end up sometime on BST to fund a Jiro