Chef knife edge thickness before sharpen..

Cushing H. said:
Actually, i find heat to be much less of an issue doing it that way. There is more mass of metal in the bulk of the blade to absorb heat, and most of the grinding is actually away from the edge itself. Also, you can actually see (looking down at the gap between the edge and the belt) as the grinding "interface" approaches the edge proper, and adjust as necessary to avoid digging into the end of the edge
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You do not want the blade to absorb heat, that heat goes to the thinnest part which is the edge. The greater surface area, the greater the friction and heat.

We do a lot to decrease heat absorption and friction by using new belts, using wet grinding or dipping the blade frequently

Doing it as I explained you still look down the edge at the gap but walking the grind up instead of trying to grind the entire surface to get to the edge help prevent overheated edge.

Do whatever works for you for sure
 
AVigil said:
You do not want the blade to absorb heat, that heat goes to the thinnest part which is the edge. The greater surface area, the greater the friction and heat.

We do a lot to decrease heat absorption and friction by using new belts, using wet grinding or dipping the blade frequently

Doing it as I explained you still look down the edge at the gap but walking the grind up instead of trying to grind the entire surface to get to the edge help prevent overheated edge.

Do whatever works for you for sure
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Hi Adam. Respectfully, I must disagree with the heat thing. Sure we want to minimize heat, but it is not a problem unless you start impinging on tempering temperatures, right? Also, the thicker portions of metal act as a "heat sink" - able to absorb more energy while not heating up so much (because of the increase in mass). There is a more technical explanation, but You guys get upset with me when I become academic about things .... do I will leave it at that.

In a way though I dont think we are really saying different things. If I understand you correctly, you are still talking about walking the grinding *away* from the edge, but you happen to be starting at or near the edge .... same result as my approach I think? I guess I just happen to not be coordinated enough to avoid digging into the edge itself if I start there... :)
 
I like Adam's last sentence, "do whatever works for you for sure". If I find a technique that lets me get the bevel I want without messing up, then I'm on it.
 
There are many ways to get it done for sure.

But if you want a "heat sink" use a jig to do it. You do not want that heat in the blade
 
FredyCro said:
You dont really need to put whole edge down when grinding lengthwise. Rotate your blade to put more surface down on the platen. I usually tilt down the heel of the knife. When evening the thickness and flatness of the grind I usually notice that my tip and heel are thicker. Switching the orientation even a bit will show you fast where the blade is thicker. Basically the same thing that N Wheeler recommends in his hand sanding video just on the grinder. Other option is grinding lengthwise on the wheel, but that takes even more practice IMHO.
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Yup, I even up my grinds by rotating it at a diagonal angle, which lengthens the surface area on the platen. Another good way to do this is on a disc sander, especially if you've got one with variable speed, so you can run it slower to keep the heat down.
 
Don Nguyen has a great video on this on his YouTube.

What I do is take the edge Dow to about 10 thou give or take. This is about the limit of what I can assertain consistency thickness wise by eyeball.

Once it is at 10 thou I chuck it in a jig and sharpen the edge. I take a bit of time here between the grinder and stone to make sure the apex of the sharpened bevel is straight.

I can now see an edge bevel along each side of the knife. Think of this as cutting your 45's again. I then go back to the grinder (I do this on a disk) and carefully grind up the grits focusing on the edge until the edge bevel is pretty much gone. At this point you should be pretty close to zero. Once sharpened again it will end up between 3-5 thou, which is imo about perfect
 
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