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View Full Version : Sharpening Problems - Not the tip...but the heel



G-rat
03-09-2012, 01:24 PM
So I haven't seen a post like this in a while and I haven't entirely seen one dealing with my question...but here goes...and at the risk of public humiliation...

I have a problem with sharpening the heels of my blades. I can keep it nice and even the length of the blade about a 3mm in front of the heel all the way to tip but at the last 3mm-4mm I end up rounding off the edge. In other words I end up with an edge that is straight from the tip to the last 4mm but then curves downwards creating a sort of frown or new belly...make sense. If you set the knife's edge flat on a flat surface the last 3mm curves upwards away from the board.

I will post pics later tonight if it doesn't make sense...

I didn't use to have this problem when I sharpened ala CDawg with the sweeping motion but my edges didn't last very long and weren't entirely even so I started watching Jon's videos and started sharpening like him. I got much much more even edges except at the heel.

I use a lot of pressure so seeing threads that said not to do that at the heel and tip I stopped but it is worse now. My heji now has the virus too and it kills me. Anybody else experience this?

Thanks for any input.

Peco
03-09-2012, 01:32 PM
I'm not an expert but I would suggest that you lighten your pressure and see what happens. I use the sweeping motion myself - absolutely no problems what so ever - especially compared to other styles of sharpening.

Benuser
03-09-2012, 02:36 PM
Are you sure your stones are flat??

The Edge
03-09-2012, 02:50 PM
Sounds to me like you are pushing the heel of your knife into the stones at the start and end of you motion. Try going a little slower and not sharpening the heel specifically. Think of the last couple of inches of the blade as one piece and keep it at a consistent angle. You won't need to put a lot of pressure on the heel to get it sharp. Also, come to a complete stop at the start and end of your motion to see where the blade ends up, should help you figure out what's going on.

JBroida
03-09-2012, 03:08 PM
lighter pressure will be very important... what kind of angle of approach changes are you making near the heel? What does your bevel look like there? Maybe some pics would help.

If you want to give me a call to talk more about this over the phone or via skype, let me know.

-Jon

bieniek
03-09-2012, 03:08 PM
If I understand correctly, you should maybe check the grind above the heel? If the metal got thicker there, also the bevel will look thicker. Examin the heel closely but look above the edge.

Is that happening in every knife?

tk59
03-09-2012, 09:02 PM
Sounds mainly like you need to slow down, use the marker trick and see where you're grinding. There is no magic. You just need to evaluate where you are grinding and adjust accordingly.

G-rat
05-12-2012, 11:48 AM
Guys -

First off I want to say thanks so much (two months later!!) for your comments on this. They have helped my sharpening in general.

Second I wanted to follow up. I am still having this issue though it is not as bad as it used to be. So now that I have a little time on my hands I wanted to post pictures and then probably a video tomorrow of how I sharpen so that I can get some critiques and figure out what the hell I'm doing wrong.

I also would really like to get this sorted out before my custom Devin Thomas line knife gets here sometime later this summer and I've got a new Zakuri petty from Jon coming soon too. :doublethumbsup:

So first some pics. I have screwed with the contrast and sharpness on these because natural light sucks in my apartment and I can't find my camera right now, so these are iPhone pics and I wanted you guys to really be able to make out the line of the edge.

First up is a Moritaka 150 petty I have had for a year and have really beat the hell out of. I actually tried to hamaguri this and ended up putting a left handed bias on it by accident. Fixing that has been a long slow process. (as in flat on the outside face, hamaguri on the inside face.) I have since almost got it totally flattened out on the inside face but not quite.

http://i189.photobucket.com/albums/z306/GratSara/photo2.jpg

You can see the line the edge makes has become one subtle and long smile. About 4mm from the heel the edge doesn't keep going straight instead it curves towards the heel making a belly that leaves the back part of the heel moving up away from the cutting board.

Second is my Heiji 240 gyuto. It is much more subtle but it is there. I have only been sharpening this knife for about 6months.

http://i189.photobucket.com/albums/z306/GratSara/photo4.jpg

Same issue just not as severe...yet...:bash head:

Finally a little bit about my sharpening style. With the Heiji I do not actually sharpen a primary bevel I only use the long and wide bevel Heiji has already ground into the blade as the only bevel I sharpen. Thus I place the knife on the stone, Push down on that bevel and begin my motions. One thing I have noticed that Jon does in his videos that last night I realized I don't do is, whatever part of the knife he is sharpening is on the stone and to some degree whatever part he is not is off the stone. Sometimes, on longer knives, I leave the heel on the stone but my pressure is somewhere else on the blade. Could it still be cutting and perhaps because of my motion (which is just like Jon's) be cutting a belly into the knife?

I sharpen the moritaka the same way. I used to think the issue was the backside of the knife when I sharpened (i'm a righty) because i couldn't get a nice even polish on the blade. I was sharpening like Jon shows in his videos where you start out horizontal on the stone and work your way to a 45 degree angle quickly. And so perhaps it was something I was doing there. I have since switched to actually holding the knife in my left hand to polish and sharpen the back side and I get WAY BETTER results...and the rounding effect isn't as bad but its still there.

I have taken almost all of everyone's advice (haven't done the sharpie trick yet) and less pressure has helped. On both of these knives you can see that the polish behind the edge follows the belly I am creating so it is clearly some motion I am making when sharpening (like Bieniek stated).

I will make a video tomorrow to show you guys how I sharpen I gotta work all day today.


Questions are:
Any more thoughts?
Once I solve the problem what is the best way to get my edge even again?

Thanks for your time.

tk59
05-12-2012, 03:47 PM
It's all about the sharpie, dude. It tells you exactly where you are cutting steel at any point. Apply it NOW all over your bevel and make a couple of normal passes and see where you are scratching.

bieniek
05-13-2012, 12:24 PM
I would like to see that video.

G-rat
05-14-2012, 09:19 PM
alright I'll take some pics later...Ive got one more test to study for and I've already "wasted" tons of time fixing this knife...

I got it straight and learned a LOT in the process. I have essentially not been cutting a bevel into the knife (this I knew) I was basically just trying to maintain the geometry and profile that the knife came with by constantly thinning behind the edge. Well we all know where that got me. It was and still is because of the backside of the knife. The area near the heel I have a hard time getting the angle correct(both the angle of the knife perpendicular to the stone and the angle of the edge of the knife against the stone) and for some reason I create a sweeping motion the gets really far behind the edge but not the edge itself. Over time it warps the heel.

So I took my diamond plate (the one from Jon Broida) and a sharpie (OK Tinh commence eye rolling and I told you so's thanks for telling me one more time) and started cutting an actual bevel into the knife. In about 20 minutes I had it nice and flat and had restored the profile of the knife. Another 30 to get that damn wire edge off from the 150 grit and to polish the edge up to 5000. Luckily my new stones came from Jon today (Gesshin 400 and 5000) man they cut faster than superstones!

I don't seem to have a problem hitting the edge of the heel on the backside but behind the heel is tough. For some reason here I can't get it to hit the stone perfectly. I can almost get it if I point the tip at like 25 degree for the perpendicular angle Regardless I now understand a little more about sharpening and maintaining a consistent bevel. I'll post a pic later tonight for now I've got some other work to do. Thanks for your help everyone. I at least feel like if I create a problem as I continue to learn how to sharpen more effectively that at least I can fix it because of the knowledge on these forums and trial and error.

G-rat
05-14-2012, 09:20 PM
And wednesday when I'm done with my damn grad school finals I'll post a video.

G-rat
05-14-2012, 10:03 PM
Ok...well here's some pics. I'm weak. As you can tell i'm also no pro amazing sharpener at all but it has a very very serviceable edge.

http://i189.photobucket.com/albums/z306/GratSara/IMG_5257.jpg

http://i189.photobucket.com/albums/z306/GratSara/IMG_5256.jpg

http://i189.photobucket.com/albums/z306/GratSara/IMG_5267.jpg

http://i189.photobucket.com/albums/z306/GratSara/IMG_5266.jpg

I know that my polish isn't that great at all. My main concern was restoring and maintaining the newly evened heel.

It needs some more work but its better than it was.

Peco
05-15-2012, 04:45 AM
Looking like you got it going :D Please post the final result when you are done ...

obtuse
05-15-2012, 01:52 PM
That is a moritaka? Could have been an overgrind near the heel?

cwrightthruya
05-15-2012, 05:39 PM
It could just be me, or a shadow that I am seeing in the second picture. But, it almost looks like you have the start of a birds beak at that tip (a common problem). You might want to be sure that you are spending enough time on the tip area and not just hitting it a little at the end of your stroke.

By the way...it's looking good.

Regards,
Chris

G-rat
05-15-2012, 05:46 PM
Yeah I noticed this last night. Funny...didn't use to be a problem for me. I could rely on the angle of the blade to keep the cutting consistent on the stone....now instead of just constantly thinning the edge my wrist has problems keeping things unwobbly...I used to sharpen that way but ditched it. I wasn't bad at it but wasn't great either. Back to the basics...Heiji is next.

cwrightthruya
05-15-2012, 06:06 PM
Wobbling does not cause a birds beak. It is caused by spending an insufficient amount of time toward the tip area and spending too much time just shy of it. Its an easy fix. But, I would suggest working on the Moritaka a little more until you figure out why you are getting the uneven grinding at the tip. Not only is it a smaller knife (making it a little easier to sharpen), but it is also less expensive just in case you screw up. Once you figure out what in your technique is causing you to develop the birds beak and get that worked out, then I would say it's safe to move onto the Heiji.

G-rat
05-15-2012, 07:54 PM
Well too late for that one...I even put it on the diamond plate!!! :shocked3:
Its better but not by much...Sharper than ever though. I still can't figure it out. Regardless I have no skin left on any of my fingers...hurts bad to type.

One thing that amazed me was how easy it was to de-burr/de-wire edge the heiji. Baffled at that. Perhaps it just doesn't abrade quite like the paper steels.

But I'm basically throwing in the towel at this point. I feel much more confident moving slowly across the stones than I used to because of wobble. Realizing that wobble isn't as bad as say whatever the hell it is I'm doing wrong. Its all because of the backside too. The front side (I'm right handed) is a breeze. I can polish and sharpen it perfectly. Its the backside that screws it all up. :beatinghead:

I think in time I will sort this out. Until then...well the expensive knives will just have to take a little abuse. I'm not afraid of that at all just wish it wasn't that way. I know that is pretty counter to what some here think but I guess I just think these things were made to be used and by more talented hacks than me...but still a tool nonetheless.

Thanks for looking.

Citizen Snips
05-15-2012, 07:58 PM
im glad you are getting this figured out ol buddy.

ive never had to do the sharpie thing but it does work at helping you understand where metal is coming off and get you in the habit of carefully observing what is happening every step along the way.

i would agree that you should work on the moritaka more before messing around with your beloved heiji.

keep up the pics and i would also like to see a video. i haven't seen you sharpen since you were at my house that day over a year ago.

Citizen Snips
05-15-2012, 08:00 PM
also i started doing something different on the backside that i can show you if you get some time this week. i start my new job on monday but can make time any day this week to get together and do some sharpening. my a-type and HD could actually use some work. it would be fun to get all my stones out as well as try out that gesshin 5k :D

tk59
05-15-2012, 09:41 PM
Looks like you're getting there, G. About the bird's beak, that can also be due to flexibility at the tip. If you are applying some pressure, the very tip is flexible enough to bend back so you are actually sharpening the part just behind the tip with more force. There are three solutions:
1. Lighten up on the pressure (but it takes a bit longer).
2. Put your finger on the actual tip (but then you lose some skin).
3. Increase your angle and work the tip then drop the angle until you are done with the flexible part of the tip and then sharpen normally (Don't ask me how I know but this can turn out funky if you're not careful).

bieniek
05-17-2012, 06:17 AM
I noticed something more... The front of the handle looks like you have been sharpening the handle also... That would suggest that you puch the heel too deep into stones surface, plus when you hit the handle, you wobble extra much and maybe thats when heel starts to get rounded? Just a suggestion.

maxim
05-17-2012, 06:29 AM
I have exact same petty, and its actually grind that way :( So when you try to thin the heel it hits the tang. If you try to change that you get overgrind heel

G-rat
05-17-2012, 10:36 AM
Yeah this is the only knife I've had that the handle was a problem like that. It's also as Maxim says, the only knife I have where to thin the heel you abrade the tang too. However I do think that most of my problem lies with too much pressure and working the heel too long. I'm realizing how true everyone's previous comments were about how it doesn't take much to get the heel sharp. I bought TamaneGiken's kono 240 last night to have as a carbon work gyuto and as one I can work on sharpening without breaking my heart...I just want to say again thanks for the continued critiques and comments. I will still get a video up but I think my talk about when is bigger than the time I have to execute. Soon though.

And Bryan I would love to see how you are doing the backside now. That sounds gross but you know what I mean.

G-rat
05-17-2012, 10:48 AM
Forgot to also say that it is clearly also a motion in making on the backside and not the front. Time to slow down again.