u/Optimal_Difference64

Really wanted to see what the Maruoyama Shiro Suita can do to a full size knife and the results are stunning. The stone feedback is similar to my mizu uchigumori, but definitely softer as it readily self slurries the more you work on the stone. The mud generates a thick, darker haze. Super easy to apply and creates an extremely clean and consistent kasumi, especially on a bevel with several points of convexity.

The knife itself is a custom engraved Kama Asa Shirogami #3 Yanagiba forged by Nakagawa with undisclosed sharpener.

The stone progression is the following: Morihei 500 - Morihei 1000 - JNS Red Aoto - Arashiyama 6000 - Maruoyama Shiro Suita.

This was followed by a fingerstone progression and mud from the Maruoyama. The hira, ura side and hagane were polished with diamond paste.

I decided recently to try to correct sharpening mistakes on this usuba I had for years as practice before owning nicer single bevel knives.

This blade came warped went it was new and unfortunately I never resolved them and it has developed a wavy shinogi after several sharpenings. The overall process was to undo all the warps with a straightening stick (Hizumibo), then correct the shinogi and set proper bevel geometry on the coarse stones.

Fixing a wavy shinogi is pretty tedious. You need to selectively remove metal from certain parts of the bevel, while not focusing all your time there to introduce a new low spot. Every now and then, you also need to check for warps. Every pass on the stone can take you closer or further to the end goal. I did this mostly on the Imanishi 220, moving up the to the Naniwa pro 400 and Naniwa 220 finger stones to make finer adjustments. While it's not perfectly straight, you also need to account for minimizing low spots and ensuring you keep the proper bevel geometry.

Polishing was done in several stages. On stones: Imanishi 220 - Morihei 500 - Naniwa pro 400 - Morihei 1k - JNS Red Aoto (2k - 6k) - Arashiyama 6k - Uchigumori fingerstones

This was followed by a diamond paste polish from 2k - 8k on the hagane and hira. The jigane was further refined with Narutaki Jizuya fingerstones and Koma nagura slurry.

Super happy that I was able to blend in all that convexity. Now it looks better than the expensive single bevels! There are still some outstanding low spots on the hagane, but not worth fixing IMO without compromising the bevel geometry.

This project wouldn't have been possible for the amazing people in this sub. Thanks to u/pchiggs for helping me source a straightening stick and /u/TEEEEEEEEEEEJ23 for letting me bounce ideas about fixing single bevels.

I managed to come across this beautiful stone, which was selling at a fraction of the price of a bench size stone. This marks the beginning of a new series of posts where I'm on the lookout for bargain bin jnats.

This one is koppa size and the approx dimensions are 148mm x 85mm x 23mm. I usually prefer koppa over bench size stones when it comes to polishing, as there is less area for a blade to potentially stick to a stone and cause unwanted scratches. The size on this one is tall enough to fit on to my sink bridge, and wide enough to allow me to sharpen without causing unwanted scratches... Also saves me a lot more funds to try other stones.

The stone itself is gorgeous with all the aesthetic inlusions. First pic shows the sharpening face dry and the second pic shows it wet. We have kuro-renge on the bottom half. On the top, we have some namazu and aka-renge. The stone feedback is outstanding. With the auditory and tactile cues, I can easily tell when the stone is rejecting the blade face and creating unwanted scratches. It has a similar sharpening feel to my Mizu Uchigumori. The stone is quite soft as it self slurries easily. No need to lap up mud to create a kasumi.

Polishing wise, the stone creates a dark/high contrast finish if you work up some initial slurry - see last pic. Baking soda solution is mandatory, as the slurry is pretty reactive. It's also fantastic at producing finishing edges. Compared to other Shiro Suita stones I have (Hideriyama and Okudo). This one creates a more refined edge than the Hideryama, but not as toothy. It's not as fine as the Okudo, but it's a toothier edge and more practical for a kitchen knife. No need to introduce an additional nagura like Tsushima to add more bite.

Hi all,

Wanted to share my latest pickup from the Knifewear garage sale. Before I get into specifics, here are some quick details about the knife:

• Core Steel: Aogami #2
• Construction: San-mai with soft stainless cladding
• Blade length: 236mm
• Weight: 199g
• Heel height: 52mm
• Spine thickness at handle/heel/middle/1cm from tip - 3.3mm/3.3mm/3.2mm/0.6mm
• Handle: Oval burnt Chestnut with black buffalo horn ferrule

Initial impressions:

Knifewear has been hyping these Sadamasas for a while now, and I wanted to see how it's like for myself and whether it's worth the hype. The cutting geometry of this one is quite interesting. it's like a heavier, mid weight Shindo with a more refined fit and finish.

The hira has a hollow that is prominent enough where you can feel it with your fingers. As for the kireha, it has a very slight concavity and the edge is ground thin enough to flex on a fingernail. The balance point is right where the chiseled kanji begins from the heel, making it pretty far forward. OOTB edge is excellent, it's very refined, but still bitey enough to slice through tomatoes and peppers skin. Spine and choil are nicely sanded, but not rounded or chamfered. This is more of a nitpick, but I can't complain given where the knife is being priced at.

While doing a julienne on carrots, the cutting feel of the wide bevel is extremely similar to that of a Kyuzo or Nishida sharpened Kagekiyo. In cases where you have to split a carrot or a sweet potato down this middle, it can start to wedge once it goes past the shinogi line and hits the shoulder, especially given the spine thickness and lack of a distal taper. It doesn't quite ghost through onions, but it's pretty close. Food release has been phenomenal with this one, probably the best I've seen on a wide bevel.

I would say it's worth a shot and I would place it in the same value category as a Shindo, where you get great performance for the money you put in. In the last couple of garage sales Knifewear has held, these tend to sell out extremely quick and I can start to see why. It's really similar to the thicker, black-dyed damascus Kagekiyo or the heavier stainless clad Kyuzo, but with noticeably better food release.

I figured it's about time to show off the tools that keep my knives looking and performing well. Aside from a few bench size ones I want to eventually try, I see my future with JNATs with koppa, especially with finding underrated bargain pieces or trying out examples from mines that don't get as much attention.

I've been spending several months practicing and refining my polishing technique, so hopefully these pictures also serve as a good reference for the various finishes they put on. All finishes were done on a flattened kiridashi with slurry generated from an atoma 600.

As a caveat, every natural stone is different and getting a consistent kasumi requires more knowledge and skill than the stone itself. For those who are curious about JNATs, I strongly encourage establishing your polishing fundamentals first, before easing into koppa size stones.

The stones:

Pic 1 - Bench and koppa size stones (from left to right) - Top row

• Natsuya
  • Large vintage piece, excellent particle uniformity, definitely on par with synthetics. Great for adding bite to an edge. Stropping on this with the Okudo shiro suita is a great way to touch up a blade and minimize the amount of steel being taken off.
• Aka Amakusa
  • My coarsest stone in the JNAT lineup. Gorgeous torato pattern, but can get scratchy. Mainly used to establish coarse edges that take too long on the Natsuya.
• Shiro Amakusa
  • Finer than the Amakusa or Natsuya, can clog up relatively easily. This one is considered as a Nakatoishi, however the slurry can break down to super fine particles, leaving you with a finish that Awasedo usually produce.
• Kozaki Aoto (koppa)
  • Small but mighty - medium hard aoto that cuts rather quickly, puts on a dark kasumi
• Kozaki Aoto (bench)
  • The koppa was so good that I wanted a bench size for sharpening. A lot of sandy inclusions when I got this one and I had to lap away 20g to clean up the sharpening face. This one is softer and cuts slightly slower than the koppa, but particle uniformity is more consistent. Easily self slurries and dishes surprisingly quick.
• Hard/finer Aoto
  • This one performs more like an Awasedo and is in the 4/5 hardness range. Super easy to use as a harder stone for burnishing out details. It readily accepts bevels on the sharpening surface without sticking, even if I put enough pressure until my finger tips turn white.
• Mikawa Nagura koppa
  • This one was mined in a rare strata that borders the Botan and Koma layers. As a result, it exhibits the properties of both. The finish is coarse enough to show some scratches, but also fine at the same time to reveal banding.
• Nakayama Tomae
  • Extremely hard stone and unforgiving. I'm estimating this to be 4.5/5. Too much finger pressure and you get scratches that force you back down to Nakatoishi. Dial in the finger pressure and you're awarded with a mirror like finish.
• Ohira Akapin
  • Gorgeous striped pattern when wet. Feels like a 3.5/5 hardness and produces a bright semi-mirror kasumi.

Pic 1 - Bench and koppa size stones (from left to right) - Bottom row

• Ikarashi
  • Very slow without slurry. Gives similar performance to the Aizu, but a touch coarser. Sharpening face is extremely clean with excellent particle uniformity. Can basically put on a finer version of the Natsuya kasumi.
• Aizu
  • Final Nakatoishi before jumping to Awasedo. Cuts fast without slurry and even faster with. Great as a sanity checker for flat bevels. You can realistically stop at this stone for edges.
• Hideriyama Shiro Suita
  • Finishing stone for most of my knives. As a polisher, requires precise slurry management to get a non scratchy kasumi.
• Okudo Shiro Suita
  • Not for beginners. Extremely hard stone and cuts quickly without slurry. The generated swarf is completely black. Can put on the finest yet toothy edge on a blade with proper technique. Usually reserved for my single bevels or anything that I need maximum sharpness for. Will not self slurry and tends to mirror polish. Like the fine Aoto, it readily accepts bevels without sticking. Lives up to the name of King of Suita.
• Tsushima
  • This one is an older piece that is harder and finer than the newer stones that are mined. As a polisher, puts on a bright kasumi that reveals banding. It is extremely competent as a finishing or pre-finishing stone
• Mizukihara Uchigumori
  • Great bench stone for putting on a final finish. Rated as a 3.5/5 by Maxim at JNS. Stone is pretty forgiving of bevel geometry and finger pressure, but can release larger particles that scratch up the surface ocasionally.
• Hideriyama Tomae
  • Extremely soft, coarser Awasedo that loves to generate mud. Budget friendly option for high contrast kasumi on both iron and stainlesss cladding. I used this to refinish a Kikuchiyo x Izo and the kasumi matched the OG finish.
• Aiwatani Kita
  • Similar hardness to the Ohira, but a lot more difficult to use. Rated as a 3.5/5 hardness by Maxim at JNS. Blade tends to stick with the generated slurry. Produces a darker, semi-mirror kasumi.

Pic 2 - Handheld nagura (from left to right) - Top row

Some of these serve as tomo nagura to the bench stones. I use the tsushima pretty often for the final sharpening progresion with either the Hideriyama or Okudo shiro suita. The uchigumori also gets time with polishing, as it can make some stones stick less.

• Nakayama tomae
• Okudo shiro suita
• Nakayama Akapin
• Tsushima
• Uchigumori

Pic 2 - Handheld Mikawa nagura (from left to right) - Bottom row

Super useful to have these that can change the finish a bench stone normally puts on. I also use these in several of my projects to create a bright, frosted kasumi that can start to show details. For example, the Manaka x Xinguo banding was revealed by using slurry on the Meijiro.

• Ban
• Yae-Botan
• Botan
• Tenjyo
• Meijiro
• Koma
• Ungraded

If you made it this far, I applaud you. Much appreciated for reading!

Finally thinned the Takeda Funayuki that I got a couple years ago. I wan't a big fan of original grind as it had a left hand bias and tends to wedge in any dense produce. I softened the the shoulders and thinned out the edge, bringing the bevel closer to 50/50. Added a slight hamaguri to blend everything in. I could've gone further, but I wanted to keep the s-grind for the food release.

The kireha is stone polished and it turned out a lot better than I expected despite the convexity. Approx progression is Naniwa 220 -> Morihei HI 500 -> Naniwa Pro 400 -> Shapton Kuromaku 1000 - Morihei HI 1000 - JNS Red Aoto (2000-4000) - Arashiyama 6000 - Kitayama 8000

Super happy with the results, the knife is a lot more usable with carrots and sweet potatoes and it no longer steers. It's closer to a laser in softer product and It still has the Takeda food release. However, it still does wedge in the odd case when I need to split a sweet potato down the middle. This one should see a lot more use going forwards.