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DaveRossy
06-03-2012, 10:39 AM
So I have been practicing sharpening with my Global's & Ken Onion Shun for a couple of weeks now. I feel like I am getting there and Jon and many other videos have helped. After I finish (start on a 1000 and finish on 6000) the knives are razor sharp but seem to keep that sharpness for only about a week. I am doing A LOT of prep and mostly use wood boards with occasional poly. Any suggestions at what I am doing wrong :knife:

bieniek
06-03-2012, 10:57 AM
Can you just elaborate what means a LOT?

Andrew H
06-03-2012, 11:03 AM
If you're doing a lot of prep and your standards are somewhat high a week sounds about right.

DaveRossy
06-03-2012, 11:08 AM
Can you just elaborate what means a LOT?

I prep for myself and my fiance, about 5-6 meals witch always includes 2-3 veggies and a protein. Sometimes cook for friends. Roughly, 5-15 peppers, 10lbs of potatoes, chiffonade herbs (lots) broccoli, cabbage, sushi and other swag.

chinacats
06-03-2012, 11:14 AM
I cook at least that much and my knives stay pretty sharp for a couple of weeks, though I have about 7-8 in the rotation so with one knife that may be about right. Again, that is if your standards are pretty high...at what level of sharpness would you say your knives are in after a week (90%)? Also, do you do a lot of chopping--i.e. hammering them on the board?

James
06-03-2012, 11:18 AM
wire edge maybe?

DaveRossy
06-03-2012, 11:38 AM
Not a big fan of chopping although some produce does require that. I finish the sharpening with a wine bottle cork as per Jon's video so hopefully no wire edge. maybe its the knives ?

Pensacola Tiger
06-03-2012, 11:42 AM
Not a big fan of chopping although some produce does require that. I finish the sharpening with a wine bottle cork as per Jon's video so hopefully no wire edge. maybe its the knives ?

Could be that you are putting too acute an edge on them. Have you thought of putting a microbevel on?

Rick

tk59
06-03-2012, 12:15 PM
Keeping "razor" sharpness for a week is pretty good. If you mean they just won't cut, that's another story. In my experience, Globals need fairly frequent touching up on a rod to feel nice and sharp. Shuns in VG10 stay keener longer before touching up. Are you saying all of your knives need sharpening every week? That would definitely be indicative of a problem.

NO ChoP!
06-03-2012, 01:21 PM
Frequent stropping or use of a ceramic rod will help prolong the edge....

DaveRossy
06-03-2012, 02:19 PM
Thanks everyone. I think its my fault. I love the "edge" after I just sharpened and then as I start to get through the food during the week, I notice a slight change in the feel :D

they are defiantly still very sharp, I just want them to feel as sharp after I sharpen them.........I'm sure everyone feels the same. Oh well, just have to wait for someone to make a knife that stays sharp forever:jumpy::tongue:

GlassEye
06-03-2012, 02:31 PM
If you don't have a strop, try stropping on newspaper. It works surprisingly well to help the edge feel closer to fresh after some use.

Benuser
06-03-2012, 03:08 PM
+1

mhlee
06-03-2012, 03:10 PM
Globals lose their initial "fresh sharpened" feeling very quickly in my experience. I still own three Globals, and use two somewhat regularly.

Also, what grit are you going up to? I've felt no need to go above 1000 (now 2000 after getting Jon's Gesshin 2000 stone) because going up higher in grit that than is not worth the time and effort - you may lose that "fresh sharpened" feeling in a day. A microbevel certainly can help, but I almost never do.

tk59
06-03-2012, 09:34 PM
Get a bottle of something in the 1 micron range from Advanced Abrasives. You can then just spray it on whatever you want to strop on and you're set for life. If you strop right before use you'll be good for maybe months before you need to reset the bevel.

EdipisReks
06-03-2012, 09:45 PM
i use my knives a lot, and i am able to maintain edges for long periods using a strop (i usually use .5 CrO on balsa, myself), and rarely actually have to take an edge to the stones (and when i do, it's almost always just a few passes on the Kitayama or a fine natural [this is after i have it set up how i want it, of course]). i use almost all hard carbon, but it shouldn't be too much different with decent stainless.

Benuser
06-03-2012, 10:20 PM
With the carbides of these stainless it might be a little different. Not so finely grained as some carbons. Stropping on newspaper with a lot of black ink will do a lot, though. It has to be in the 1-2 micron area.

Maluaka
06-05-2012, 12:12 PM
Ahh Globals. I have a couple that my wife uses and my inlaws have a huge set that I sharpen occasionally.

First off, they get an absolute b@$tard of a wire edge. After my 2k stone I literally drag the edge down the wooden handle of my strop to rip it off (you can see a little pile of metal left in the wood) I then do another round on the 2k with gentle pressure, 4k, then strop. I've tried higher grit but it doesn't seem to make much difference.

The other thing with globals is that, as has been mentioned, they lose that initial "fall through hanging paper" edge in like one to two meals worth of use. They keep a "good" edge for a really long time but "screaming" edges are very short lived. More obtuse sharpening angles help, but the issue seems to be more with the steel.

Crothcipt
06-05-2012, 01:02 PM
I haven't chimed in yet just because I have been testing my edges. I have finally been able to shave hair on my arm with my Globals. I only have 2 stones atm, a 1k King Deluxe, and a 600/4k combo Samurai.

After my first sharpening of the 3 knives I wasn't happy with what I achieved. They had a edge but they were not what I like for a edge. So I started over again. I couldn't feel any burr forming at all, but just did touch up on the 600 stone. Then on to the 1k, still no noticeable burr but still a edge. Then the 4k with heavy pressure, the stone made some swarf so I knew it was cutting but nothing noticeable except a shinier bevel.

I then stropped on leather. I used to use telephone book pages but it took quite a while for a noticeable change. I can now get a screaming sharp edge, but it wont last very long at all. I will just strop again to get it were I like it. Also the hrc on Globals is 56-58, which is why (I can be wrong here so please let me know) it wont hold a "screaming" edge for long.

Also I have noticed that a weird angle is needed to get there. Almost a 45 degree angle or higher.

Benuser
06-05-2012, 01:12 PM
My Globals respond very well on leather + Cr2O3 at an angle of 25 degree inclusive. That 45 degree is a microbevel I guess?

Crothcipt
06-05-2012, 01:44 PM
I was thinking that when I went that way, but I got a very good response with it.

SameGuy
06-05-2012, 02:11 PM
I love this forum. That's a LOT of info from practical experience in a very short number of posts! Would Dave's boards have quite a bit to do with his edges? I relegated my poly and crappy edge-grain boards to dog-food prep with my crappy knives once I started using J-knives for all my people-food prep. That said, I get about two weeks out of my white-2 KS edge with somewhat less prep than Dave describes.

Crothcipt
06-05-2012, 02:16 PM
yes and also technique will also do it to (rock chop). More time on the board will dull it too.

Maluaka
06-05-2012, 06:44 PM
yes and also technique will also do it to (rock chop). More time on the board will dull it too.

Or in my mother in laws case, daily runs through the dishwasher despite my pleading with her not to :curse:

45 degree seems really excessive. I dont measure my angles but I definitely go more obtuse than on my own knives. It seems like every global with a factory edge I get to sharpen is chipped to heck. Don't know if this is the steel or the users but it seems to be a theme. After I first sharpened ours (still at fairly steep angles) the chipping issue seemed to be less. Of course I started with my 220 to set an entirely new bevel.

My theory as to the problem many have is due to the factory bevel being very convex. If you don't reset the bevel on a very coarse stone you would need to sharpen at an excessive angle to even be hitting the edge. If you sharpen at steep angles (close to the stone) you will only be hitting the shoulders.

I probably sound like I hate globals but I really don't. I think they are the best of the "Williams and sonoma" type knives as far as profile, geometry and grind go, I just find the steel a bit lacking in edge holding as compared to something like VG-10.

Crothcipt
06-05-2012, 08:06 PM
I don't have any way to check the angle I am using just because it is freehand. It just seems more extreme than others.

Benuser
06-05-2012, 08:34 PM
I tried it, and stropping at a much higher angle does work, without lost of performance. Whatever your sharpening angle is (25 degree inclusive?), 45 degree is a lot to strop at, but 35 degree is quite reasonable.

DaveRossy
06-07-2012, 09:06 AM
Thanks everyone, I will look into some leather for stropping and give it a try. Just a footnote, I just got my ceramics back from Kyocera from the sharpening dept (only $10) and I would LOVE to have an edge on my regular knife like I have got back on these. I can just pull the santoku back from the heel to the tip on a lemon and.....right through :eek2:

Cadillac J
06-07-2012, 09:55 AM
I would LOVE to have an edge on my regular knife like I have got back on [Kyocera ceramics]. I can just pull the santoku back from the heel to the tip on a lemon

Trust me, in time you will think that same feeling is somewhat dull once you get going on sharpening. In my experience, ceramic knives cannot even come close to how keen and sharp an edge can get on a good blade.

DaveRossy
06-07-2012, 09:42 PM
Trust me, in time you will think that same feeling is somewhat dull once you get going on sharpening. In my experience, ceramic knives cannot even come close to how keen and sharp an edge can get on a good blade.

You had better not let ming tsai hear you say that :doublethumbsup: