Tag Archives: Blue Aoto #2000

How to sharpen a Global knife

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How to sharpen a Global knife

How to sharpen a Global knife

Some beautiful Global knives

I love Global knives, they are light, they stay sharp, they look good, and they are extremely easy to keep clean and affordable. So it really makes me sad to see how many of them that is ruined from bad sharpening, miss aligned edges, wrong edge formation, wrong edge bevel angle, overheated from grinding machines and belt sander, bad finish and so on. If they are sharpened the right way they are one of the best knives you could have, but with a bad sharpening job they might not be better than anything else.

This is how ordinary Global knives (not single beveled) should be sharpened: 

–          They should be hand sharpened on Japanese Water Stones.

–          The edge formation should be slightly convex on the back end of the edge bevel.

–          The edge should have a 15° angle, but it is possible to give it a slightly steeper angle if needed.

If you follow this links to their sites, you could check it out yourselves.

Edge formation: http://www.yoshikin.co.jp/w/craftsman/index.html

Sharpening: http://www.yoshikin.co.jp/w/maintenance/maintenance_01.html

Hand sharpen performance: http://www.global-knife.com/catra/index.html

The little video above shows what performance you should be able to expect from a newly sharpened Global knife. Maybe not, if you prefer an edge with more bite, but you should at least be able to slice thin slices of tomatoes and shave with it when it is newly sharpened.

The knife in the video a customer came  in with, it had be sharpened for the first time the week before of another sharpener. She told him that it wasn’t as sharp as she had expected it to be. His response was that it was sharpened to factory specs, and that a resharpened knife never could be as good, as it was when it was new. First of it wasn’t sharpened to specs, it had an uneven bevel, the bevel wasn’t convex, and the edge bevel were close to 22°, the edge was very rough and still had a burr. With some luck she might have been able to slice a thick printer paper, and maybe it was a bit sharper than when he started sharpening it, but it wasn’t gorgeously Global sharp. It is definitely possible to getting a Global knife sharper than it was when it was new, check Global’s CATRA report on the “Hand sharpen performance” link above.

The knife above I gave a little more finish than needed, just to make her happy. Anyway here is how I got it back in shape, started with DMT and Chosera #400 to clean it up and set the new bevel, after that I went straight on to bester #2000 that is one of my favorite stones, it cuts fast and gives a great edge. After that I used Blue Aoto before finishing on an uknown #6000 and a #8000 Kitayama, finally I gave it a light strop on leather loaded with Mothers Mag & Aluminum polish (be careful clean the knives several times after, that polish is definitely bad for you if left on knife) Usually I don’t strop customers knives, but thought it would be fun in this case and it definitely improve push cutting performance.

Magnus Pettersson hand sharpening, now serving the whole Westside with free pickup and delivery: Santa Monica, Brentwood, Pacific Palisades, Venice, Marina Del Rey, Culver City and West LA.

For free pickup and delivery on the Westside, call/txt 310-486-6068 or email.



Knife repair, giving new life to a broken knife

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Santa Monica Knife Sharpening
old broken knife with chipped edge

Unsharp broken knife before regrinding

This knife was given to me by a good friend, at first look it doesn’t look to bad except for the big chip right there the heel starts. After a closer look I realized that the primary bevel was concave and parts of the edge was folded over, I also realized that the secondary bevel was way wider in the back and at the tip. Look at that tip I could have folded it by hand, it was thin as aluminum foil. At the moment I just saw two different ways to fix it, one was to leave the primary bevel concave and try to give it a new edge on the side of a sharpening stone, or regrind a new flat primary bevel and give some sort of compound edge. I decide to give it a new primary bevel to get rid of all edge damages and big scratches on shinogi.

illustration of edge before and after regrinding

Illustration of edge before and after regrinding

Above is a little illustration what it look like before and after, and what I would like to achieve. First I went to work with a large blacksmith file, because of the amount of material that I needed to take off, just to realized that it didn’t give me much precision, tried a bunch of different coarse stones, the one that eventually seams to do the best job was Beston #500. With this stone I worked until I got an even flat primary bevel all the way to the edge, I also used it to set the secondary bevel. After that I changed to King #1000 to smooth both bevels out and did some initial sharpening. After that just a fast brush with Bester #2000, before starting with my favorite stone it’s a man made blue Aoto rated to #2000 but feels much finer. This blue Aoto gives that perfect mist to the soft steel on the primary bevel, its super soft and have great feedback; the only thing is that if you don’t want your hand to look dirty for days after, use glows. For final sharpening and finishing on the secondary bevel I use Kitayama #8000 also a great stone, after this just some light stropping, before setting the micro bevel with Shun #6000 wish gives a nice bite to the edge.

I also did some clean up and light polishing just to make it easier to clean, I’m using it daily now, and its one of my favorite knives. I realized that I’m not good at always cleaning and drying the knife after use, so it started to get some stains/rust on the pretty mist on the primary bevel, so I gave it a light polish with #2000 sandpaper and all is good now. Yes of course its sharp, not hair popping sharp, but sharp enough to shave with or to slice cigarette paper into small strips. Pictures of the knife after regrinding below.

Knife after repair, regrinding and polishing

Knife after repair, regrinding and polishing

Magnus Pettersson hand sharpener, now serving the whole Westside with free pickup and delivery: Santa Monica, Brentwood, Pacific Palisades, Venice, Marina Del Rey, Culver City and West LA.

For free pickup and delivery on the Westside, call/txt 310-486-6068 or email.




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