# Thinning a Henckels chefs knife



## bennypapa (Jan 25, 2016)

My first good chefs knife was a second hand Henckels Pro S that I still have and it needs some TLC.
There appear to be 2 bevel angles and it looks like it needs some thinning.
I'm a terrible knife photographer so I don't have any useful pictures so instead I took some measurements that might be helpful. If you have any lighting or photo tips please let me know.
The face of the blade is barely convex near the bolster but flattens as it moves towards the tip. From the top of the edge bevel to the spine it is very close to flat. The top of the edge bevel is about 0.07" from the edge and about 0.025" thick.

What kind of edge geometry should this knife have and do you have any tips on how to get it there?

I'd like to have an even finish on the face of the blade. As it stands the faces are a mixture of polished spots and multidirectional scratches and I don't care for how it looks. I'd much rather have a uniform finish even if that aspect eds up being another thread.

I know this is a bit of a "making a silk purse out of a sows ear" situation but I would like to learn what I can from this knife and improve its performance and aesthetics as much as I can.

At my disposal I have a course and fine diamond plate (about 320 and 600 grit respectively), a suehiro 1000, naniwa aotoshi 2000, and various wet or dry sandpapers.

Any help or advice would be appreciated.
Thanks


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## Benuser (Jan 26, 2016)

That will be a big operation with such an abrasion resistant steel as Henckel's. Have no experience with diamond plates, I would start with automotive sandpaper on linen, P120 to start with, at the lowest possible angle, until you've almost reached the very edge. With sandpaper, use only edge trailing strokes, and have a hard rubber or soft wooden support to avoid facetting and allow smooth convexing. 
But I would start by inspecting the profile for evenness and absence of a reverse belly. And see if the fingerguard doesn't cause a protruding heel which is the very first thing to correct.
Perhaps it's a better idea to send it to a competent sharpener. Again, with such a steel it will take almost forever.


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## WingKKF (Jan 26, 2016)

Thin it out enough so it won't wedge or pop off carrots and you should be set. Practice makes perfect and sharpening is like a zen thing anyways so try it out on a cheaper knife first if you don't want to risk your Henckel. Appearance should be secondary to functionality and if you're using rough diamond plates the scratches will be nasty and deep anyways so don't worry about it. Maybe next time you might want to get waterstones for low grits instead.


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## Benuser (Jan 27, 2016)

You may start thinning by only easing the shoulder, where the bevel begins and makes a sharp edge with the blade. When the blade is there .025" thick you want it to be reduced by the half, at least. To get there you will scratch at least a third of the blade. More likely even up to the half.


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## Benuser (Jan 27, 2016)

The shoulder is where bevel and blade meet in a dead angle. Hope this is a bit clearer.


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## bennypapa (Jan 27, 2016)

Benuser said:


> The shoulder is where bevel and blade meet in a dead angle. Hope this is a bit clearer.



That shoulder description makes perfect sense. I guess I'm wondering if I could maybe use the thickness that I have to build a little bit of convex into the face of the blade. That idea will have to wait. The bolster needs to be ground down below/behind the cutting edge first and that could be a long process that I may start on my bench grinder. I have a 220 grit wheel on that.


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## Nomo4me (Feb 12, 2016)

I thin - very successfully - on a low speed belt sander. With a wide selection of belts, platens and lots of experience powered systems can be applied to even high quality knives. 

I know for a German knife I'd never spend the time on stones. 

I'm new here and sorry for the heresy.


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## jacko9 (Feb 12, 2016)

I've thinned German knives on the Atoma 140 diamond plate then finished up with a ******** 150, Shapton Pro 320 and Shapton Glass 1000.


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## rick alen (Feb 13, 2016)

Do you really want to trash a good diamond plate removing the huge amount of metal that knife would warrant removing?

For the fun of it I've done serious thinning on some clunky-thick soft stainless knives like your Henckles (well it was actually clunkier even) using a bench grinder, dremel and a cheap course/fine combination India stone. Made it really thin at the tip with lots of distal taper the last 3.25", and thin at the edge with nice asymetrical convexing to 5/8" from the the spine for the rearward portion. It's hours of work to do a 9" chefs, bench grinders with cheap wheels aren't all that fast, and you have to be careful not to burn things or grind into your edge. Belt sander mucho better, but I had the grinder and wasn't about to spend money on a BS, that would be just BS to do just for that project.

For a school-project you'd be better off buying something like a beat-up carbon Forgecraft to play with, less metal to remove but still reasonably over-thick, and much less abrasion resistant. Eh but she's your baby, do as you will, just letting you know what's involve.


Rick


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## psfred (Feb 13, 2016)

German style knives don't do well with a very thin profile or acute sharpening angles, they are too soft. I would definitely use a belt sander, I tried to thin a soft steel knife once and gave up, never did get it thin enough to use. Put a big dish in my King Deluxe 300, a stone I normally only use the flattening stone on to get a fresh surface it wears so slowly.

I would recommend an inexpensive guyto, Tojiro DP or something similar and skip all the work to find out you still have a heavy, fairly blunt knife.

Peter


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## rick alen (Feb 13, 2016)

psfred said:


> German style knives don't do well with a very thin profile or acute sharpening angles, they are too soft.
> Peter



I had some knives even softer than Henkles, but I think that .008" behind the edge is likley going to be too thin for the Henks too. Hit a bone and the edge just takes a bend set. 0.010" did OK for a Vic (came .015"), with limited abuse, so I guess the Henkles will handle that also, but .012 would be safer.



Rick


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