Primary Bevel Grind

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muddpuppy

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Feb 1, 2025
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I am new to knife making and getting frustrated with primary bevel grinding. It seems every one I do somehow turns into a recurve blade. Anyone else ever run into this and know what I am doing wrong. Any help would be appreciated.
 
Can you post a picture of an example? It will help to see the type of pattern you're attempting, and then we can share some tips.
 
If you mean the edge curves up in the middle, it is usually caused by unconsciously twisting the blade slightly as you go from plunge line toward the tip. This situation is sometimes called the two-inch line or two-inch spot. Basically, it is caused by spending too much time on the middle of the blade when you are trying to get the plunge even. Spend less time as you go past ten middle and try to hold the blade evenly. It takes time and lots of practice to get if figured out.

A carbide shoulder guide will help a lot.
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One of the training videos I watched long ago talked about subtly rocking the blade as you grind along the length. Flat Grinding by Harvey Dean.

“Two inch mark” at its most extreme means you get a recurve. Imagine a 3.5” blade. If you keep a full 2” of bevel in contact with the belt, with even pressure, that stripe of 1/2” in the middle will have abrasive going past more than anywhere else, so more gets ground off.

If you have the belt cutting in the plunge, put a little more pressure with the hand on the handle than the hand pressing the tip. If you were to look down from above along the length of the platen it’s like the blade a seesaw, but not all on the very edge of the belt! It’s subtle, just to have the belt cutting on the half of the belt nearer the plunge than it is in the other half. When you move the blade across the belt, you rock it back so that it is even in the middle then pull the handle a little towards you when you are grinding near the tip.
 
Another tip is to look down what will become the edge frequently (every time you dunk to cool) to see how consistent the thickness is. Focus your grinding on the thicker areas until it’s consistent from heel to tip. I know this will seem like a captain obvious statement but remember; you can’t grind out a low spot, you have to grind the high spots around it.
 
How many knives have you made so far?

It takes awhile to work out all the stages.
Every stage has potential for issues.

I agree about getting a carbide bevel guide.
I also started getting better knives when I upgraded my platen to carbide.

But everything takes lots of practice. Relax, build some confidence, keep grinding. The more you do the better it gets.

-also, are you grinding hard or soft steel?
I grind everything Hard. I think it's better.
Stainless seems gummy if ground soft.

Grinding hard is Slow....
But it also then takes longer to make mistakes
 
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