Thread: My kit of Japanese knives ... WIP

I have just spotted another blue steel kitchen knife with SS cladding (and available locally here in Australia) that can be added to those that I posted earlier here and here.

Syousin Chiku by Yu Korusaki

PS - Some of the earlier knives I recommended are no longer available and some of the alternatives suggested by the vendors are not SS clad, so ask about the cladding before you buy.

Stay sharp

Neil

I took some shed time today to work on the Shimatani Deba. After the mishap chipping out the edge I'd reworked the bevel on a wet grinder. That left a couple of dips in the bevel with coarse scratches. Those were today's target.

With a knife jig for the ProEdge I thought a bit of belt work would do the job quickly. But no. The bevel angle changes, diminishing towards the tip. Didn't want to change that, and the knife is not the best fit in the jig anyway.

So I took to the bevel with some diamond hones - medium to super fine. That took out the dips with the scratches but left a pretty ordinary finish.

Time to do it properly, on the wetstones, starting from scratch (ahem). Did a bit of research on the method *. Started on the back for the uraoshi. Hmm. Some distance from flat (see pics). I hadn't worked on it before. Had to go down to #240. Then #400, #1000, #3000 and #6000, alternating back and bevel. Not a bad result. The #1000 impressed with how quick it cuts this blue steel. It's a Sigma PS II like the rest except for the #400 which is a Stu special. That worked well too.

The distinct micro-bevel from new is now gone. I'm wondering about reproducing it. I assume it's done for strength.

Lastly it got a clear lacquer spray to avoid stains along the lamination lines.

So now there's a bunch of stones that need flattening.

* https://www.youtube.com/watch?v=qSAL2OnQdA0

Deba 1.jpgDeba 2.jpg

Thanks for that post Ern.

It is good when you get to that stage when you can confidently rehab/reset the geometry of a knife. It is also good to arrive at that stage when it is time to remove some of the metal from the edge of a knife as supplied by the maker; the more you remove the less chance there is of having any brittle surface metal remaining.

On micro-bevels, I'm progressively adding them to the knives that I maintain and especially on those that have been given a hard time by their users. I'm finding with the less acute angles on the micro-bevels I'm getting those knives back less frequently for rehabbing.

There is also another factor; you can use different levels of abrasion for the main 'blade path' and the micro-bevel. I like to take the actual cutting edge to the highest grit I can manage and I can do that more often and take a lot less time to bring the cutting edge back up to super sharp on just the micro-bevel. And, with the high cost of the super-fine finishing stones, you are not going to wear away an expensive finishing stone so quickly if you are just using it on micro-bevels. I'm talking about sub-mm micro-edges here, like 0.25-0.5mm, and only just visible to the naked eye under direct lighting. Unless it is an aesthetic consideration for you, the primary bevel surfaces doesn't need to be anywhere near as fine as the cutting edge. In fact, a lower grit finish will release food more readily than a highly polished finish.

Ern, the Deba is a good candidate if you are thinking of experimenting with micro-bevels again.

Neil

Thanks for those comments Neil. Good points about a micro-bevel. Will give it a go.

Sooo ... thinking overnight about how to do it. The bevel is 15 - 20 degrees. Clearly need to avoid over-stressing the edge. I'm wondering about pushing the bevel skewed down the stone with light pressure. What do you think Neil?

OK, Ern.

This is what I'm currently doing when I'm re-sharpening a micro-bevel.

Probably best shown with a short video.

This is the result. With the sun on it the micro-bevel looks bigger than it is. I estimate that it is only about 0.1mm wide.

Microbevel off Nakayama Lv5.jpg

I took a very blunt edge (knife would not hang on my thumb nail inclined at 45deg) on this blue steel petit to sharp in 21 strokes on each side, ie alternating 10, 5, 3, 2, 1 strokes on each side on a hard (Lv5) stone. Use your finest stone for this. The number of strokes required will vary on how blunt the knife is, the hardness of the steel and the aggressiveness of the stone. if I resharpen as soon as I'm not happy with the cut I'm getting I usually only need ten strokes on each side on my combination of knives and stone to come back up to very sharp.

Hope that is of some help.

Neil

PS - if you click on the knife image you can see that I have slightly rounded over the heel (choil) of the knife. I find that I get along with my knives a bit better with that done...

Thanks for this instructive tutorial Neil.

Yes, my choils get to kiss some abrasive too.

With all the kit out I decided to give the ko-deba the treatment too.

This hasn't had much use and was still adequately sharp. The back needed a deal of work; even for what's probably white steel it's quite hard.

Took it down to #10 000 and put a micro-bevel on it and on its big brother. Pretty polished Neil from the synthetic.

As a by the way the JP knife book says not to bother with a shiageto (extra fine) on stainless blades as the serrations formed are too small to catch the material being cut.

There's some useful info at Hocho Knife | Japanese Kitchen Sushi Knives including this schematic of steel types:

grade-of-steel.jpg

This second site's worth a look too if you're in the market for another knife. Looks like an aggregator/translator of Japanese web pages. Downside is that there's often not much tech info. Rakuten Global Market: Kitchen knives - Cooking & Confectionery Goods - Kitchen, Dining & Bar

For travels and for the less experienced at home I've laid in a santoku again. It's a Yaxell VG10 165mm. A bit on the showy side but the fit and finish are very good and the price was right. It only needed a blade clean and spray of lacquer. It's a 70/30 grind with a canvas-micarta handle.

There's an aircon in the shed and on this stinker it's a good place to be.

Thought I'd have a play with an el cheapo felt wheel and some Veritas honing compound, the first try with this kind of gear. The compound is said to produce half-micron scratch marks.

The focus was on improving the finish on some of the blades - removing original grind marks and cleaning up lamination lines. It worked very well and warrants scaling up to a larger wheel.

It left a somewhat hazy finish on a Tanaka VG 10 while on the glide path of the Shimatani (blue steel and stainless) the result was on the mirror end of the continuum.

Next, to see what it does for edges. But seeing what's happening isn't easy.

There is going to be some sharp knives in your kitchen this Christmas, Ern.

I agree with your J-Knife book, there is little benefit in taking a V10 stainless edge into the very fine grits. The higher up in that useful diagram above you go (from bottom left to top right) the greater the benefits there are from a super fine edge in terms of durability. The downside is those steels are harder to sharpen and also the more brittle they are. A micro-bevel alleviates some of the tendency to chip in those high carbon/temper knives.

As you are going to have to resharpen stainless and white steel blades more frequently, anyway, I don't find it is worth the effort myself of taking the edge up into the finest grits. On the other hand those relatively softer steels are more suited to blades for chopping.

I like the hammer pattern in the cladding on that Yaxell VG10. Besides the pleasant hand crafted appearance, those dimples are going to help release the food as you slice it.

Stay sharp

Neil

Yeah, 'fraid they're too far up the blade Neil to do much good.

This morning I charged up a leather belt with the Veritas honing compound and put a micro-bevel on the little Deba. Wow, scary sharp gives way to spectacular sharp.

Next I think I'm going to have to degrade the edge on the petty knife so it does better on tomatoes!

Originally Posted by rsser

Next I think I'm going to have to degrade the edge on the petty knife so it does better on tomatoes!

The ripe tomato cutting test is an interesting one, Ern; while the flesh becomes very soft, the skin remains tough. Pressing firmly to penetrate the skin with a knife that's not sharp or toothy enough will squish the flesh before it cuts the skin. A micro-tooth on the knife edge seems to help commence a slicing cut through the tougher skin.

Stay sharp

Neil