Sharpen a New Tojiro Nakiri

I just bought a Tojiro DP F-502 nakiri. This is my fourth Tojiro and I love them. When I took the knife out of the box, I wiped it down and tested the edge for sharpness...it cut paper like crazy. I used it to slice 3 cloves of garlic, wiped it off and retested the edge. It wouldn't glide through paper, just tore it. I felt the edge and it had a "burr" on one side.

What's going on, and what should I do to resharpen? I have a Shapton glass 1000 and 2000 and a Chosera (either 4000 or 5000) plus courser stones.

Thanks

Factory edges are kind of blah. You need to set your own bevel and polish it up to about 5k. Just go from the 1k right to the 5k and you should be fine. Here is a video demonstrating double bevel sharpening on a gyuto. The same principals apply to a nakiri.

[video=youtube;bMW5vJ4krPE]https://www.youtube.com/watch?v=bMW5vJ4krPE[/video]

Theory is right that factory edges tend to be sub-optimal, in general. However they will normally be serviceable (depending on the manufacturer, from just ok to very good).

In your case, it seems like the factory edge wasn't properly de-burred, and the leftover burr folded over right away. This also happens sometimes to beginner hand sharpeners.

Same fix in any case: just sharpen it yourself and you'll be fine.

Thanks all - Ran a Shapton 1000, 2000 and Chosera 5000 progression followed by stropping on "green leather". It's sharp now. Hope the edge holds.

The new edge will hold. Factory edges tend to be brittle for some reason.

Factory edges tend to be done on machines like the Tru Hone where the knife is pulled through some spinning stones. It does come out very sharp, but also extremely hollow.

I usually start with a somewhat coarser stone when removing the factory edge. When you start with a 1k it may take a few sharpenings before the edge gets stable.

Tojiro DPs have a reputation for having a "chippy" edge the first couple times they are sharpened. I suspect this is due to the high speed power sharpening used at the factory for the initial edge plus the rather extensive grinding they undergo, all by power machinery. It is also possible there is some loss of carbon at the edge during heat treatment, causing the edge to be weak. Removing this weak, overheated metal by sharpening a couple times eliminates the problem.

My gyuto has indeed accumulated a large number of tiny chips in the edge since I sharpened it the first time, just barely visible. Probably not helped by my sister in law using it, but what can you say?

I'll be sharpening today, we shall see what happens. By all reports, this issue goes away once the initial apex is removed, and the edge becomes quite stable and stays sharp very well.

Another issue is the fact that VG-10, even very well heat treated, as Tojiros usually are, is difficult to de-burr, and "chips" in the edge can simply be a small burr failing in use. A few sharpenings will take care of that, too, as you get used to the knife.

Peter

My initial effort with the Shapton 1000, 2000 and Chosera 5000, didn't hold up, so, as suggested I'll drop down to a 400 to remove more of the factory edge and then run the 1000, 2000, 5000 progression. I can go lower than 400 if you think I need to remove more steel. What's the consensus?

Alan

No need.

Two days imo means you likely didn't get rid of the burr. Stainless is a ***** to learn to sharpen...stick with it.

Did you strop it?

I did strop. My usual progression is Shapton 1000, 2000, Chosera 5000 and strop on "green leather". I noticed that the bevel is smaller than on my other Tojiros. Should I work more steel off to get a bigger bevel? Is 15º about right for this knife?

Thanks

Alan

I don't like stropping stainless, except for very finely grained ones. With VG-10 I believe it only weakens the edge without removing the last burr remainings.

Benuser said:

I don't like stropping stainless, except for very finely grained ones. With VG-10 I believe it only weakens the edge without removing the last burr remainings.

Click to expand...

So how do you finish off your stainless knives?

malexthekid said:

So how do you finish off your stainless knives?

Click to expand...

Very light edge trailing (stropping motion) and deburring on 5 & 8k. Not looking for a high polish, just for burr reduction and abrasion.

Strange, got a new Tojiro Nakiri dp and the factory edge is holding up so far.

With all due respect, it will depend on your expectations. Many users here require a level of sharpness that is far beyond what is needed in Western kitchen. A thin blade will perform quite some time even when not very sharp. And VG-10 is known for losing its scary sharpness very quickly, but keeping an acceptable level of sharpness for a very long time after that.

As I mentioned, my first two Tojiro's (a petty and a Gyuto) were scary sharp out of the box, and stayed that way. My third, a paring knife, needed a little touch up. The Nakiri was very sharp out of the box, but the edge "folded" with minor use. I sharpened once, but the edge didn't hold, so, I'll resharpen. Since the Tojiro's are all machine sharpened, I expect it's a QC issue at the plant.

I have two bonus questions

Recently i bougth 3 Tojiro DP knifes, out of box they were paper cutting sharp, but after a couple of weeks they have lost some shapness.

1.
What is the best way to keep the knife shap between the shapning sessions?

2.
I can understand that i need to make a new egde insted of the fatory´s but is it crucial as fast as possible, or could i just wait to i don´t think the performance i acceptable any more?



/Mathies

Often do touch ups on gesshin 4k. If I think it needs it. But I haven't had to yet on my tojiro.

I can't wait with new knives. Sharpen them as soon as you can. And start far behind the edge.

I should have added: start with a relatively coarse stone. I start with a Chosera 400.
As for maintenance, strop and deburr on your finest stone. If you don't get it done with a few strokes, go to your second finest one, and so on.

Benuser said:

I should have added: start with a relatively coarse stone. I start with a Chosera 400.
As for maintenance, strop and deburr on your finest stone. If you don't get it done with a few strokes, go to your second finest one, and so on.

Click to expand...

Thanks for you answer, it was very helpful.
Unfortunately I´m not the owner of a #400 stone.
I only have a flattening stone grain 220, KING 1000/6000 and some leather strops..

Can the King 1000 do the work or do a have to buy a 400 also ?

With a 1000 it will just take a bit longer to remove some steel.

alfreedo said:

My initial effort with the Shapton 1000, 2000 and Chosera 5000, didn't hold up, so, as suggested I'll drop down to a 400 to remove more of the factory edge and then run the 1000, 2000, 5000 progression. I can go lower than 400 if you think I need to remove more steel. What's the consensus?

Alan

Click to expand...

Since the suggestion was to remove more steel behind the "weak" edge, I ran the following progression on my Edge Pro: EP 240, EP 600, Shapton glass 1000 and 2000, and then stropping on a Chosera 5000 and "green Leather. May have been a bit overkill, by the knife is now sharp. Will have to wait to see how it holds up.

so, i picked up a tojiro dp petty and the edge rolled over after about three weeks of light use. I guess it is a QC thing.

It isn't the edge that rolled, it's a burr. Soft German edges roll, a VG-10 edge won't roll, it breaks.

my mistake the burr... there was a noticeable burr on face of the blade.

I have not sharpened a DP in a while had one that used as pass around & sold had a thick wa handle paid 99.00 3 years ago. Could not resist the 58.00 240mm wt. free shipping on Amazon. Reading this thread with interest. I plan to thin it put a good edge on and use as pass around in beginners class that mostly use kit knives Mercer millinium with full heel bolsters.

Looking at 10" Victorinox with rosewood handle cost 70-80$ these days. I think a thinned DP is a better knife. Of course here I go again think the Tojiro powder is a steal at 130.00.