Making first kitchen knives, can use some advice

S

Sprayman

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Nov 15, 2014
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Hello, Friends;

I'm beginning a project that is new to me in a couple of ways. I'd love to get some advice.

Tomorrow I begin making my first kitchen knives. I have some .125 thickness 1084, which I decided on because in my (limited) experience, 1084 is pretty easy to work with. Before I start grinding the blanks, I'm going to make a jig out of angle iron, following instructions I've found on this forum. So, my questions are as follows:

1. At what angle should I grind the blades for a good FFG?
2. I don't have a bubble jig, so I'm unsure how to set the angle for the jig. Will a standard protractor work, or is there another method?

Thanks!

Geron Spray
 
The angle you set your jig at will vary dependent on the thickness of the stock and the width of the bevel. There is a chart online that will give you this info. Just Google "Steven Penner blade angle chart".
A protractor can be used to set the angle, or any of the digital angle finders that are available.
 
With a FFG, you don't have to worry about the angle. Just grind it flat down to the edge. ;) On a think badly like a kitchen knife, I would recommend doing most, if not all of the grinding post HT. You can thin out the stock a bit beforehand if you so desire and maybe put in a little distal taper.
 
Hey Sprayman, when i first started making kitchen knives i had the same question. Its a little trap you run into. In truth, the angle is what ever it takes to go from spine to edge.
 
Correct, the primary bevel angle is of no importance. It is whatever is formed from spine to edge. The secondary angle made when the blade is sharpened is what is important.

On 1/8" stock, the best method is to grind in your profile and distal taper and do the HT. Then do the bevels post HT. This removes all decarb, reduces warp, and assures good edges.
 
jdm61 said:
With a FFG, you don't have to worry about the angle. Just grind it flat down to the edge. ;) On a think badly like a kitchen knife, I would recommend doing most, if not all of the grinding post HT. You can thin out the stock a bit beforehand if you so desire and maybe put in a little distal taper.
Click to expand...

Thanks for the feedback. What's the purpose for/advantage of doing the grinding post HT?
 
Stacy E. Apelt - Bladesmith said:
Correct, the primary bevel angle is of no importance. It is whatever is formed from spine to edge. The secondary angle made when the blade is sharpened is what is important.

On 1/8" stock, the best method is to grind in your profile and distal taper and do the HT. Then do the bevels post HT. This removes all decarb, reduces warp, and assures good edges.
Click to expand...

Stacy;
I have yet to grind a distal taper. Are there any tutorials or videos that you know of, or do you have any advice?
 
Greenberg Woods said:
Hey Sprayman, when i first started making kitchen knives i had the same question. Its a little trap you run into. In truth, the angle is what ever it takes to go from spine to edge.
Click to expand...

That makes sense, although I'm a bit worried about appearance. I don't want to be able to look down at the top of the knife and see one side at a sharper angle than the other. That's why I figured it would help to know the angle, so I could set it the same on both sides.
 
I'm confused as to why everyone would tell the OP the angle does not matter. Agreed, if your grinding freehand you grind from edge to spine, but the OP is wanting to set the angle on a sled. You could grind and set, grind and set, until you got the angle you needed, but why not set the angle close to what your finished angle will be to save yourself time?
 
What you do is scribe the centerline or parallel lines for your projected edge thickness, onto the edge of the blade. Grind down to it with a steep 45 degree bevel on both sides.
Then grind your flats until the 45 degree bevel has just vanished, and the grind reaches the spine. Same as any knife. It'll save your belts too. No fiddling about with protractors or jigs necessary.
As far as saving time, in the end the fairly easily gained ability to freehand grind will do that.
 
You guys are awesome. I hope you find some nice hunks of steel in your stockings this Christmas. :thumbup:
 
NC Biker said:
I'm confused as to why everyone would tell the OP the angle does not matter. Agreed, if your grinding freehand you grind from edge to spine, but the OP is wanting to set the angle on a sled. You could grind and set, grind and set, until you got the angle you needed, but why not set the angle close to what your finished angle will be to save yourself time?
Click to expand...


Whether using a sled, angle jig, or freehand, the actual angle is insignificant. You adjust things so it grinds spine to edge leaving an edge that is about .020" wide. If you tried to pre-set a jig, you would need one that was lab grade rock solid and setable to .0001 of a degree. For example, a .125" thick blade that will have an edge of .020" and a blade height of 2.000" would form a right triangle to the edge of .050X2.00X2.06' That would make the acute angle 1.4321 degrees ... see what I mean. If that was 1.4 degrees (more accurate than any jig) it would come out .100" short of the edge/spine, most likely making the edge too thick. 1.5 degrees would overshoot the edge/spine and make the edge too thin.
 
The actual number of the grind angle is not really important its being able to contact the belt consistently what ever the angle is. Now if your goal is to make an identical blade more than once, knowing the angle makes this much easier, especially if you don't have a lot of experience. Since I grind using a Bubble Jig, I have patterns for knives I will make often and have the grind angle marked on the pattern itself. This makes the process much easier. All the blades in a set will match using this technique.

Have a great holiday gentlemen, Fred
 
Stacy E. Apelt - Bladesmith said:
Whether using a sled, angle jig, or freehand, the actual angle is insignificant. You adjust things so it grinds spine to edge leaving an edge that is about .020" wide. If you tried to pre-set a jig, you would need one that was lab grade rock solid and setable to .0001 of a degree. For example, a .125" thick blade that will have an edge of .020" and a blade height of 2.000" would form a right triangle to the edge of .050X2.00X2.06' That would make the acute angle 1.4321 degrees ... see what I mean. If that was 1.4 degrees (more accurate than any jig) it would come out .100" short of the edge/spine, most likely making the edge too thick. 1.5 degrees would overshoot the edge/spine and make the edge too thin.
Click to expand...

Hey Stacy,

I understand the math involved and appreciate your time and explanation, but when using a sled, you have to start somewhere. I don't use a sled anymore and freehand my grinds, but when I used a sled, I would set the beginning angle based on the thickness of the stock, height of the grind and using a digital protractor set to 100th of a degree, I'd come pretty close to where I needed to be when I got down near my edge scribe line or spine, whichever came first. I could then finish up by hand and get the grind flat from scribe line to spine. Isn't calculating the approximate angle based on stock thickness and height better than just arbitrarily picking an angle to set your jig? Like I say, you got to start somewhere.
 
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