Problem sharpening Aogami Higonokami with Sharpmaker

I think it depends on the kind of steel, how hot it got and how fast it cooled again. On my BG-42, the overheated part was very hard but crumbled like a pototo chip. Had to use a magnifying glass to see the tiny chips but I could even flake off tiny bits digging by fingergnail sideways on the edge. If I tried to cut some soft wood with it, the edge became more like a saw with very tiny teeth.
 
I can feel it by finger where the edge is rough, chipped and where it starts cutting. So far - more I sharpen, longer sharp part of the blade near tip comes (may be it is my imagination - will see). Again I think it is local defect, because blade near tip is perfect and also I don't have same problem with my other local Japan knives with warikomi (but Shirogami).

The thing you had with BG42 may be more mechanical impact of grinding of overhardened blade, probably same I have.

Thanks, Vassili.
 
Well, nozh, if you get too frustrated with it, you could sent me one of those that you have problems with and I give it a try on some decent waterstones. I hope I have been around this place that this offer doesn't come across as a scam. If you want me to give it a try, you can drop me an email, and we can work something out. Please take this just a well meant offer. Otherwise I hope you have some success soon.
 
nozh2002 said:
The thing you had with BG42 may be more mechanical impact of grinding of overhardened blade, probably same I have.

Thanks, Vassili.
Click to expand...

No, not impact. Heat. I think SOG used one of those computer controlled industrial grinding machines like this one http://www.anvilusa.com/Auto_Grinders.htm to make them, and maybe the coolant ran low while it was grinding the knife I got. The bad steel near the tip of the blade was a different color. It looked kind of blue when you reflected light off it, while the good steel near the back of the blade reflected the silver-white color of ordinary stainless steel.
 
HoB said:
Well, nozh, if you get too frustrated with it, you could sent me one of those that you have problems with and I give it a try on some decent waterstones.
Click to expand...
Thanks a lot HoB, I am not too consern about knife being sharp but about me being able to sharpen it. If it is not defect in HT, I like to know how to sharpen it. I sharpening it almost all day today and I thing I see little progress. However, I am triying to figure out what it is.

Thanks, Vassili.
 
Now I am pretty sure that blade is undertempered. I sharpened it different ways with gently touch and a lot of water - it is steel chipping on the edge.

However I don't want to give up yet.

The question is how to fix it? If it is zone tempered using clay or something? then I can remove underhardened part by continue sharpening. Otherwize I have to temper it myself - Does anybody know what is tempering temperature for Aogami. May be I may use kitchen owen for this?

Thanks, Vassili.

P.S. No replay from Kukihide yet.
 
Give it a try on a waterstone. I am pretty sure it will behave completely different on a waterstone. Chipping just doesn't sound like undertempered.
 
nozh2002 said:
then I can remove underhardened part by continue sharpening.
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Nope.
The edge is very high carbon steel, forge welded between two layers of lower carbon steel, or sometimes wrought iron.

Please try a waterstone. Get an 800 or 1000 grit to start with. This grit range is the best compromise between sharpness (1000 is already shaving sharp! (If you want to get really anal retentive, grit size goes gets as fine as submicron 12000 grit!)), price, and speed of sharpening. The continuous exposure of fresh material makes sharpening very fast, while the slurry that forms during sharpening acts as a finer grit.

A beginner waterstone is not very expensive.
http://froogle.google.com/froogle?sourceid=navclient&ie=UTF-8&rls=GGLC,GGLC:1969-53,GGLC:en&q=japanese+waterstone&scoring=p

I suggest Lee Valley. They carry only items of good quality, ship quickly, good price and have a longstanding good reputation. (they have stuff custom manufactured for them!)
Lee Valley's lineup of waterstones: http://www.leevalley.com/home/Search.aspx?c=2&action=n

I got the large 1000/4000 stone from them:
http://www.leevalley.com/wood/page.aspx?c=2&p=33009&cat=1,43072,43071
A little pricey for this particular one, but this is because it is the equivalent of two full sized stones, one with the more expensive 4000 grit. I am very happy with mine, and want to get a somewhat coarser one (800 grit or lower) for even faster removal of metal when reprofiling.
 
My conclusion is based on the fact that I heve this problems only on part of the blade! If it is well tempered - why then first inch of the blade is just perfect and I have all this problems in the middle and then another half inch near the handle?

Thanks for this great links, I gues I must have this waterstones - this is part of the knife culture and I have now Yanagiba and Deba so I should sharpen them with authentic stones.

Let me get it and try, but I think that it will not help. It is most likely undertempered.

Thanks, vassili.
 
Today I bougt Ice Bear waterstone 1000/6000 combination - Harima Enterprises from Miki City (same city where higonokami from). I tryed to sharpen Higonokami with 1000 first - all chips goes away, after I was satisfyed with 1000, I continued on Sharpmaker Fine and then UltraFine - it works just PERFECT! It shaves as I expected from quality steel (Bule Steel, BluePaper (label) Steel -Aogami).

Thanks to all of you for this magnificent advise! Vassili.
 
Excellent! That is very good to hear. Try the 6000 side as well, you will be surpised how smooth an edge the waterstones can form.

Yuzuha, I agree. I think "King" is the name of the company and "Icebear" is the lable under which they sell their stones....or the other way round, I forget. I have the same 1000/6000 combination.
 
I just complete my set with 800/4000 combination. And this is Samurai Deluxe Water Stones - really King Water Stone Co. LTD. Ise Bear is Harima Enterprises - different brand. As well as they both made in Japan I have no conserns.

Thanks, Vassili.
 
I really didn't mean to say that you should have any concerns. Was more of a technical matter.

I have this one:
http://www.bladegallery.com/accessories/accessory.asp?id=7
(actually the small one, but the picture of the small one shows the other side)

It came in a box that said "Icebear" but as you can see, the side of the stone says "King". This is why I assumed that they are somehow related.
 
Mine Ice bear has also label "King waterstone" and also mark - ice bear is registred trademark of Harima Enterprizes. May be it is made by Harima for King Waterstones? Does not really matter.

I am wondering why I have this problem with Medium stones and it is OK with Fine. It is defenetly not about pressure level or something like this, I tried to sharpen it on Medium without pressure at all and same ceramic Fine works well. It should be some mismatch on steel versus ceramic grane size level.

Thanks, Vassili.
 
This is a really old thread, but...

I just bought a higonokami as well (the cheapest one, S55C steel) and it didn't come as sharp as I would like, so I tried to sharpen it on ceramic rods (crock sticks + UF Sharpmaker rod) and I can't get it to shave. A little part of the blade shaves, but the rest seems to stay at the same sharpness.
 
Goosey said:
This is a really old thread, but...

I just bought a higonokami as well (the cheapest one, S55C steel) and it didn't come as sharp as I would like, so I tried to sharpen it on ceramic rods (crock sticks + UF Sharpmaker rod) and I can't get it to shave. A little part of the blade shaves, but the rest seems to stay at the same sharpness.
Click to expand...

Bump again, I kept sharpening it to try to wear down some of the metal, and then I used the flats of a Sharpmaker UF rod to try to get it shaving. Nothing seemed to work.

Eventually I managed to get it a bit sharper, so I decided to strop it on cardboard and bam, it started popping hairs... only on one side of the blade, so I assumed it was a wire edge.

Some more UF rod and more cardboard, and now it is popping hairs on both sides of the blade. For the time being...
 
I will try it Goosey as i'm putting the Higo on the ceramic yesterday and it has the chippy edge on it.
 
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