Beginner Grind Question

colu41

colu41

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Dec 24, 2014
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I've read multiple write ups and watched dozens of videos, and of course everyone does everything different. My question is, when starting to grind the blade, do you grind to center FIRST, then go from there to get your grind height up the blade? Or do you gradually work it?
I've seen some people do both but I'm looking for the easiest way for a beginner.
 
I prefer Full Flat Grinds.
With the eventual edge up I start at the plunge line/heel area and draw the knife across giving it a distal taper.

The few that I hollow grind I start more in the middle and work it both directions.

Does that help?
 
I'm still very much a beginner but I grind the corner (at the edge) first then gradually reduce the angle until I get the grind height that I want. Then I grind at that angle until pretty close to the centerline and do the other side. Make sure you don't overshoot the centerline.

The reason I do it this way is I know where the corner is. Someone better at it might be able to eyeball the angle well enough to do it the other way.
 
Rhinoknives1 said:
I prefer Full Flat Grinds.
With the eventual edge up I start at the plunge line/heel area and draw the knife across giving it a distal taper.

The few that I hollow grind I start more in the middle and work it both directions.

Does that help?
Click to expand...

Sorry I may have worded that wrong. By center I mean the center line that was marked on the blade to center the edge.
 
Hmmm?
OK, I start with a 36 grit and take off about 60% to the center grind lines. Then a 60 grit for about 60% of the steel left to the center grind line then to a 120 grit to take it the out side edge of the scribed lines then its finishing time.'

Does that help answer your question?
 
Rhinoknives1 said:
Hmmm?
OK, I start with a 36 grit and take off about 60% to the center grind lines. Then a 60 grit for about 60% of the steel left to the center grind line then to a 120 grit to take it the out side edge of the scribed lines then its finishing time.'

Does that help answer your question?
Click to expand...

That makes perfect sense when doing full flat grind. Which with a little bit a fooling around in the garage I may do my first few knives full flat. I tried it out on a practice knife and turned out decent.
Is a full flat grind a little easier than say a "half" grind or high grind line?
 
colu41 said:
That makes perfect sense when doing full flat grind. Which with a little bit a fooling around in the garage I may do my first few knives full flat. I tried it out on a practice knife and turned out decent.
Is a full flat grind a little easier than say a "half" grind or high grind line?
Click to expand...

My reason for preferring a FFG is that you don't have this resistive chuck of steel at the top while slicing and chopping. Since I make mostly culinary knives and a few hunters it's the best ergo for me. If you want to go more of the sharpen pry bar route, stopping at half or 3/4 can make sense.

You do have to get both sides even thought!;)
 
colu41 said:
Is a full flat grind a little easier than say a "half" grind or high grind line?
Click to expand...

In some ways, yeah, it's a little easier. With full flat there's no visual indication to show that the grind on one side of the blade was at a different angle than the other. Also a partial flat grind that isn't perfectly done can have a wavy grind line. At least one of my previous attempts at a high flat grind resulted me abandoning it for a full flat grind because I had trouble getting it perfect.

Also full flat you don't have to worry about screwing up and getting belt scratches above the grind line.

Go make some blades!
 
Thanks guys. I finished both sides my practice knife with a full flat grind and it turned out pretty decent for my first attempt. Not what confuses me is, how far down do you take the edge before heat treating? And how bad is it really on the belts when finishing the grind when it is treated? I don't want it too thin that it warps but I dont want it too thick to where I where out all my belts too quick. (btw, I have a 1x30)
 
Is the most common practice to grind the bevels by laying out your edge thickness on both sides leaving .020" on the edge then grind high angle passes until you hit or just about hit the line on both sides of the blade edge then start working up the blade leaving a slightly visible witness along your original high angle grind?

Not sure if that makes any sense. I can visualize it easier than I can describe it. I guess I'm meaning sort of the way you would do it using a filing jig by establishing your edge thickness first and foremost then slowly working the bevel higher w/o completely violating the grind your used to establish your edge. Maybe that's a better way to word it.

Jay
 
colu41 said:
Thanks guys. I finished both sides my practice knife with a full flat grind and it turned out pretty decent for my first attempt. Not what confuses me is, how far down do you take the edge before heat treating? And how bad is it really on the belts when finishing the grind when it is treated? I don't want it too thin that it warps but I don't want it too thick to where I where out all my belts too quick. (btw, I have a 1x30)
Click to expand...


Just under the thickness of a dime is a fine gauge to leave steel at the edge prior to heat treatment.
 
Rhinoknives1 said:
Just under the thickness of a dime is a fine gauge to leave steel at the edge prior to heat treatment.
Click to expand...

Thats super awesome to know! Now is that for all different types of steel? I've heard horror stories of people getting warped blades back from .03-.04 thick edges. But just looked up the thickness of a dime is about .053 lol. So maybe thats all the difference. Thanks again Rhino!
 
I do all of my bevel grinding After HT and that alleviates that warping issue. I use modern stainless, Cpm-154, 440C Cpm-S35VN etc.

for years I would leave them about the thickness of a dime then after HT I would take the edge/bevels down to .30 to zero depending on the kind of knife.

What steel are you using?
 
Rhinoknives1 said:
Just under the thickness of a dime is a fine gauge to leave steel at the edge prior to heat treatment.
Click to expand...

I used to say that too....until I realized it is twice the max edge thickness desired. A dime is 1.4mm or .055". Half the thickness of a dime is where most new makers want to be at HT.... .025-.030", or .75mm. On stainless steel, . 015" is the max, with .010" being the norm.
 
Rhinoknives1 said:
I do all of my bevel grinding After HT and that alleviates that warping issue. I use modern stainless, Cpm-154, 440C Cpm-S35VN etc.

for years I would leave them about the thickness of a dime then after HT I would take the edge/bevels down to .30 to zero depending on the kind of knife.

What steel are you using?
Click to expand...

Starting out with 1084, then I also have a chunk of CPM154 coming also. Depending on how these turn out, I may mostly use 440C & 1084. If I find any high end stainless at a good price, I'll pick some of that up too. Like the CPM154 I ordered is an 1/8th 1.5 x 12 for $16! Thought that was a decent price.
 
Dime thickness or under a dime...whatever you are comfortable with.

Lot a guys finish up the grind post heat treat and it gives them some room to work with if there is any warpage.

What I have seen hanging out at TruGrit with the heat treat are blades that are ground far to thin pre heat treat.
 
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