Miyabi Black ZDP189 knives sharpening angle.

[ValeryD]

Hi all,

Just recently the knife I bought on sale arrived. This is Miyami Black, Prep, 140mm long. Contrary to what users of this knife write in their reviews, this knife cannot be described as sharp in any way. It is very roughly sharpened. Probably something around 800-1000grit. A dense row of sharpening scratches is clearly visible on the chamfer. The knife cuts poorly, very far from what was expected.
Now it is clear that the knife needs sharpening. On the website where such knives are sold, the description of the knife indicates that the sharpening angle is usually in the range of 9 - 12 degrees. It's pretty vague. I would like to know this angle (the best one) more accurately. Therefore, the question is: have any of you dealt with Miyabi Black knives and do you know what angle is recommended for these knives? If there are no such users, what have you heard about this?
How to sharpen and to finish when sharpening such ZDP189 steel knives?


Thanks in advance.


Valery

[atang]

Congrats on the recent knife! I have sharpened the Miyabi series knives though not specifically their MC66 line. Sounds like it could use a fresh bevel. Diamond plate will make it easier to do so. Zdp189 can take a 10* edge. Maybe add a little microbevel depending on your cutting board material. I think you’ll like the edge from a strop loaded with diamond. Do you have any pics?

[jmcnelly85]

High hardness supersteels are capable of extreme edge angles, but not all knife users are capable of extreme edge angles. There is no “magic angle” that others can tell you to use, start by following the existing angle, if you start noticing early microchipping then ease back in the angle until you find one that suits your needs as it relates to your skills, board, and products used. If you haven’t noticed any microchipping and feel you could squeeze some extra performance out, try having a touch steeper of a bevel next time around.

The more you sharpen your own knives, the more harmonious you will be with it. What will work for someone with a nice end grain board and a light handed technique cutting nothing but occasional fruits in the morning will be different from someone who regularly cooks with lemongrass, or a heavy handed speed chopper killing 80 lbs of onions on the worlds worst polymboard and then having the shit kicked out of it on a pro kitchen line.

You have a very capable knife, some people take these knives to extremes and are fine, some people find their limits and get some serious chips, pay attention to what your knife is telling you and find the right balance of edge angle that suits your needs. The answer you find will evolve as your skills evolve.

[Radar53]

Some great advice above. I think there's a real temptation to take many new things to their limit, right off the bat. Often that doesn't work out for the best. Earlier in my days on this forum, I used to say the I "like to creep up on my edges" as it gives both me and the knife some wriggle room.

in the famous words of Mr Miyagi ~ "Patience Daniel-san, patience"

[salemj]

I personally have more success with bigger angles on my short pairing knives. If you measure a 10 angle on a knife that is less than 1 inch tall, it means the spine should only be off the stone by about the height of a nickel or less in most cases (remember that you measure the angle to the center of the spine, not its edge, which means a 10 degree angle that is 4mm high is likely less than 3mm off the stone when measured from the bottom face of the spine). Depending on the knife and its geometry, this makes it easy to both scratch the blade face and to miss the edge during the stroke.

While I've tried hard to sharpen blades this way freehand, I just have way more success when I go for something closer to 15-20 degrees on my pairing and petty knives. If the blade geometry is very good (a thin knife and thin edge), the apex geometry on a knife like this will make imperceptible difference in actual use. I would recommend not overthinking the angle. Instead, with a very hard steel like this, choose an angle you can maintain and start with a very low-grit stone to ensure you put on a new, consistent bevel. Then work up from there. For a petty this small and a steel this hard, I wouldn't go above 5k freehand...you simply cannot be that accurate with the shape to reap benefits (personally, I'd stop closer to 3k and then just strop). If you have a jig, going higher is much easier.