Dealing with the Bolster?
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Anyone have suggestions for sharpening this knife? The stone is hitting the bolster/finger guard and thus I can’t sharpen the end of the blade. I thought about using my work sharp/belt grinder to just grind down the bolster. Is there a better way? or a trick?
Knives with full bolsters are difficult to sharpen as you get closer to the bolster. I don’t really understand the attractive features of the full bolster design. In my assessment, it makes the knife a lot heavier than necessary, upsets the balance point of the blade, and prevents proper sharpening without extra work to expose the edge by grinding the bolster back.
I would say that the belt grinder is the way to go in order to take the bolster out of the way prior to sharpening. Here’s an example of how you might go at it:
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Good video.
I run in to a few of these “concave bellies” every year and I do them very much like the video. I try to remove enough of the bolster to allow for several sharpenings before it becomes a problem again.
One thing I’ve done is to sand about 10mm of edge back with the bolster. This moves the heel away from the bolster and helps you to avoid hitting it with your stones.
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The next issue you’ll run into is the fact that normal strokes must stop at the bolster. This means that the heel of the edge will get little or no sharpenings and soon you’ll produce the same flaw. I start my strokes with a distinct loop at the heel before continuing with a straight diagonal stroke for the rest of the blade. Strokes beginning at the tip are done in reverse. I really should have a diagram, as it’s hard to explain with my limited vocabulary. Imagine looking at the knife from the left side and our strokes will be edge-leading, starting at the heel. You start with a downward motion at the heel, following an arc to a tangent point. The arc is part of a circle about 1.5″ – 2″ in diameter. You start at 3 o’clock, then follow the arc to about 5:30 o’clock, where you switch to a straight line which is a diagonal line moving toward the tip. This motion allows you to apply about 0.75″ of abrasive work at all points along the blade. You can duplicate the effect when starting at the tip, where the “loop” will be executed at the end of the stroke, or for edge-trailing strokes. Try not to run the stroke dead-vertically at any point, as the resulting scratch pattern will be noticeable. If you do see this difference in scratch pattern, you can then focus on blending this section into the rest of the blade.
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Eric you definitely should customize the bolster so you can sharpen the knife. Wusthof is a fine German Steel knife. Definitely worth the effort.
Marc
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I believe the Patron Saint said, “it should eliminate the bolster problem for a sharpening or two“. But don’t hold me to it. I don’t think it’s too bad for what looks like a well used, maybe a $100 knife.
Marc
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It looks like he went from 420+ to leather. He did not really solve the long term bolster issue for his customer. That knife will be back with the same issue.
Unless you are going to eliminate the full bolster completely the sharpening problem will always reoccur. I would not buy a knife with that type of bolster but companies like Wusthof and Zwilling/Henckels sell knives like these at a cheaper price and a lot of people buy them. The issue of the blade bellying is from sharpening without dealing with the bolster. The knife in the video was probably over sharpened in some type of powered sharpener that is not capable of dealing with the bolster issue. After a while the knife doesn’t work worth a darn so now the bolster has to be dealt with. This is an issue that the WE is not going to be much help with it’s own.
I don’t think there is a better way to handle that particular sharpening and retain the original geometry. Those knives will always have to be dealt with, shortening the bolster, or eliminating it and by doing that you are creating a new knife essentially.
Most knives that cost more than $100 or so have a guarantee and in most cases lifetime sharpening. If you sent the knife in the video back to say Wusthof , I would bet that they would deal with that bolster in the same manner as the gentleman in the video.
Personally I think the gentleman in the video did the job in the correct manner. That is right up until he put the blade on a belt sander to sharpen it anyway!!! That is how most sharpening services are going to do it though. Right or Wrong! I have shortened a few of these by hand with a grinder, file and sandpaper and it takes a crazy amount of time, to much time if you want to do a good job. A knife grinding rig is essential equipment to deal with “fixing” some blades unless you are willing to put hours and hours into doing one knife that in a lot of cases didn’t cost $40. Most of the cheap knives have this type of bolster.
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