Sharpening a Grafting Knife

[Skinnygoomba]

This is how I sharpen my grafting knife;

I have a few important tools for this;

DMT flat coarse diamond plate
Naniwa Chosera 1000 & 3000
Shinden Yama Renge Suita
Tomo Nagura
Water
Rubber mats



I have two diamond plates, I decided to switch the better one right off the bat...sorry for the bait and switch.

The back of the blade has a dished hallow leading out to a flat edge at the front (cutting edge) and part of the back, the purpose for this is so that the leading edge can be flattened successfully and maintained easily. I put an initial flattening on the back with my diamond plate, but then I rarely ever touch it again with anything other than my finish stone.



This is the initially flattened back



I soak my naniwa stones at this point, preparing them for the next step, to work the back through 1000



At this point I should have a good burr on the beveled edge, so I will then flatten my beveled edge with 1000 grit until it is flat and the burr has gone to the flat side of the blade.



Next I soak my 3000 and have a servant deliver a snack.





At this point, things are looking good, I have a very flat edge without areas indicating they are out of flat. I can see the weld line between the hard and soft steel.

Next I am working with my 3000 grit stone, which this Naniwa is one of my favorites;



The back is so flat and polished that it can stick to the stone. This can be annoying but I use enough water to minimize it and clear the swarf.

I have turned the blade over and brought the bevel edge up to a 3000 grit hone as well.

Next, I do not soak my shinden stone, it is far too precious to co-mingle with the lower stones. I put a little bit of distilled water on the stone and use tomo nagura to build a slight slurry.



I am working through the back and edge moving the burr back and forth and polishing both sides will maintaining the geometry of the blade.



Now I have a good finish on the back leading edge and also on the bevel, the weld line is clearly defined and everything is very sharp. My final step is to strop the blade on a good clear strop until the wire edge has completely diminished.

 

[whfarro]

Thanks for posting this. The pics are much appreciated.

 

[Brian Van Fleet]

Is that how you would sharpen mine if I sent them up
This is an area I want to improve, but I never knew where to start with all the different stones.

 

[FrankP999]

Great post and photos. Brian, by the way, in the world of sharpening knives, a discussion of different stones will evoke as many opinions as a soil thread evokes here. I recently went down that rabbit hole and was amazed at the variety of stones used to sharpen and the progression from 200 grit to 30000 grit or higher. The key is precise control of the angle of the blade edge on the stone. I have bad hand-held control so I bought a tool/device to give more precise and repeatable angle control.

Skinny, Thanks. Great photos!

 

[Brian Van Fleet]

Frank, I can see that being the case...which is why I prefer to know a guy then be the guy who sharpens tools. I know a bonsai guy here in town...slightly OCD who doesn't sleep, sharpens tools so well, they cut your eye just lookin' at 'em.

 

[barrosinc]

Thanks for the pics! appreciated!!

It would be awesome if you could document how you sharpen the weird shaped tools, like concave cutters, branch cutters... I have trouble even cleaning those!!

 

[Skinnygoomba]

Thanks Gents, glad you are enjoying. Brian, as Frank mentions, you can fall down the rabbit hole quite easily;
I chose coarse diamonds/1000/3000/suita/strop, I have previously used 1000/6000, coarse/1000/8000, 1000/3000/8000 with King's and sun tigers. I have also lucky enough to stumble upon an excellent advisor who saved me a great deal of money in trying stones and time wasted. My current process is the result of those efforts and I know it works because it produces a good cutting edge, which after bevel setting can be maintained very easily with the suita and strop.

I have refined my process for woodworking, but since these are tools and similar enough they're easily worked through the same process. Infact a grafting knife is nearly identical to a kiridashi woodworking knife and obviously the carving tools and chisels are also the same.

The steels that are used by Japanese makers work very well with the Japanese sharpening routine (no surprise there) as most of there synthetic stones are designed to cut hitachi white and blue steel backed with plain iron. Natural stones are a specialty in itself, but the suita I have is excellent for tools and cuts these steels as hard as they can be made (Koyamaichi white and blue steel chisels are harder than this grafting knife based on how easily it cuts). The 'sword' steels and special blends by maker are slightly tougher to sharpen, but will do so in the same method.

I like diamonds for bevel setting, flattening and only bevel setting and flattening, they are coarse and do not create a good edge even at their highest rating. They cut fast, require very little in the way of maintenance and double of stone lapping tools. So I set the bevel with them, then move forward to water stones.

I like Naniwa chosera synthetics, they're excellent stones and once soaked for 5 minutes behave quite nicely, the 1000 cuts very quickly by comparison to similar 1000 grit stones, and the 3000 is really sweet to use. My only gripe is that they load up with swarf, however this can be easily mitigated with technique.

The only really outlandishly expensive part of my routine is the natural stone, the Shinden Suita, it's a rare stone from a closed mine that produced excellent stones, sold by an honorable seller. It's not something required by any means, infact it's quite an indulgence. I have used the Naniwa snow-white 8000 to finish blades and it is an excellent stone.

So, for those that end up getting into it, this is my routine, but obviously this is the tip of the iceberg when it comes to stones....you can take many paths that lead to success.

 

[Skinnygoomba]

Barros, Absolutely, I'll give a write up as I go. I have only a small amount of trees so my bonsai tools remain sharp for a great deal of time.

 

[sikadelic]

Great post. I only have a few stones and a Lansky system for my knives.

For my tools, I have a small extra fine diamond stone and just give them a few passes every time I pull them out. How do you sharpen yours?

 

[Skinnygoomba]

I sharpen scissors on my same stones, but not every use. I'll go through each tool as the need presents itself and post up photos.

 

[M. Frary]

What the hell is the snack? Mountain oysters?

 

[thumblessprimate1]

Thanks for the nice write up complete with photos.
The snack looks good. Homemade? Oriental for sure, but from which country?

 

[Skinnygoomba]

Any Asia-Philes will know. They are chinese and the translation is something to the effect of 'balls'. They are filled with sesame.

 

[thumblessprimate1]

It looks like a Vietnamese dessert that I've had. Tapioca balls filled with mung bean in a syrupy liquid. Yum.

 

[MidMichBonsai]

I think I'll just stay away from commenting on the snack that is translated "balls"...oh wait, did I just inadvertently comment?

 

[M. Frary]

That's what mountain oysters are.

 

[Giga]

Great write up! I actually got into a little metal work last year. I have a sword now, a kitchen knife and 2 grafting knifes-though I think yours might slice threw my katana

 

[Skinnygoomba]

Cheers!

I think I'll just stay away from commenting on the snack that is translated "balls"...oh wait, did I just inadvertently comment?

Best part is that they're typically served in pairs, lol.

 

[sorce]

Goomba,

I like the article. But I would rather ship stuff to you for Sharpening!

Sorce

 

[sdavis]

Any suggestions on choosing a grafting knife?