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CedarSlayer

What are the qualities of a good head knife?

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Any good tips on Making a Head Knife?

I am cheap, poor, a beginner at leatherwork and like to make my own, so I am going through the work to make a few nice head knives.

Head%20Knife%2004%20Cut%20to%20Shape.JPG

The steel plate I am cutting from is a nice 7/64" thick chunk of old stock Sheffield O1 steel. This is seriously great steel. Easy to temper, and will easily sharpen to as good an edge as any steel known. Some metals will resist wear better. A lot of metals resist rust better, but for sharp, O1 is the classic great.

Here is the lot of them cut out. The red shows me where to grind off the edge to get an even circle.

Arc%20Scribe%2001%20Bottom.JPG

I made a radius cutter so that I could mark a radius around a center point. I plan to attach the grip with Chicago Bolts, but leave the center hole. With a correctly placed stud in the hole, this will allow easy sharpening to an even edge. As the blade is used and wears down, I can grind the stud down to maintain the angle.

This brings me to a few questions.

My plan is to put the bevel on the blade to 15 degrees, and then to put a 18 degree secondary bevel on that with the reference angle stud to allow the 18 degree angle to be maintained. With a washer on the stud, I could then put a micro bevel on the edge to 20 degrees, if desired. Do these angles make sense or are there traditional leather working knife angles that work better? My leather working experience is pretty small, so I have no clue.

Also, I put blade reliefs in as I have seen them on a lot of examples. Usually a blade edge is given the cutout, to facilitate easy sharpening. However the few examples of head knives that I have seen, do not have the back edges, the ones facing the users hand, sharpened. Does anyone sharpen these?

If there are any other qualities that are ideal for a head knife, I would be grateful for the suggestions.

On another note, I am planning to make a few blades for leather cutting that will fit into the radius cutter.

Arc%20Scribe%2003%20points.JPG

It will help me make nice curves in leather. I am poor and cheap, so I have to make my own tools, but if you are interested in the radius cutter, Lie-Nielsen offers one.

Mine will open to make a very large circle, and is totally stable. Considering the source, I suspect that the Lie-Nielsen version is every bit as good if not better.

Arc%20Scribe%2009%20opened.JPG

Bob

Edited by CedarSlayer

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Ceder,

If I were you, I would avoid putting two individual bevels to my knife. I prefer my knives to be one long taper from handle to cutting edge. Fairly thin is good but don't go to thin or that edge will roll easily. I use mostly antique blades, your W. Rose Knives, Gomph, and Theo Harrington are my favorites.

The Rose knives were made to heavy in the blade, so whenever I get one I tend to take alot of material off with a power sander and like 80 grit paper. After that I continue to work it with finer and finer sand paper till its polished, always keeping that taper the same degree from handle to edge. After its polished the way I like then I take it to a stone and thats when I will put a second bevel on it. But its a very fine one. You have to remember that with a Round knife there is no tool to maintain that same exact degree when you sharpen it. With a pocket knife or kitchen knife there are a multitude of tools to sharpen them with, by hand or even a machine. But with a round knife you are pretty well stuck with by hand.

I know that this may not sound very scientific but when I sharpen a knife, I guess at the degree of that edge that is being sharpened on the stone. I could send you a picture of a good knife to show you thickness of blade as well as the straight bevel that I'm talking about. Like I said I'm not very scientific, but I have gotten to were I can put an edge on one of my knives that I can shave with in about 10 minutes. And with good steel my knives hold that edge for a long time. Another thing one you get that edge on there and you knife is sharp, buff the snot out of it. If its good steel, you will get them scary sharp. Let me know if that helps and if you want some photos or not.

Ross

nrcowboygear.com

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Ceder,

I pretty much would echo what Ross said. I too use Gomph and Rose head knives, and I have had to remove shoulder approximately 3/4" from the edge back on all of them. I also like Buchman's knives and have had to dress them the same way. I have always assumed that the old knives were forged as they have a definite taper from the tang all the way out to the cutting edge. Mine are all about 3/32" thick at the tang. Someone once told me what kind of steel was used in them and why todays tool steels don't work as well, but I don't remember the explanation....I'm not really sure I ever understood it. What I have learned by making my own mistakes with these old knives is that once their temper is lost, they're never the same! Bob Douglas was telling me one time that they (I assume he means Herb French and himself) have tried repeatedly to re-temper these old blades that had been ground down and lost their temper, with no success. For that reason alone, I sharpen all of mine by hand also, which makes it difficult to try to maintain the compound angles as Ross mentioned. For me, I want a blade that is as thin and hard as it can possibly be! I don't worry about what it takes to sharpen them....the harder they are the longer the edge lasts....thats what I'm looking for. Hope this helps.....

Bob

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I had some designs critiqued many years ago by a couple of knife makers that created round/head and 1/2 round/head knives for Marlin and here's some things that they said.

The knife edge for round knives should only be made one of two ways...

(1) Taper from the edge to the tang

(2) A taper 3/4" back from the edge of the knife

Their preference was (1) because the knife edge was always thinner until you were about an inch to inch and a half from the tang but it also required the knife to be thinned each time as it was sharpened. Whereas (2) maintained the same edge throughout the life of the knife.

Also none of them liked the full tang because you could not modify the handle to fit the user properly.

Hope that helps.

Regards,

Ben

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Thankyou for the input, Ross, Bob and Ben! Your suggestions make perfect sense. My personal preference is for a single bevel so I think your preferences are wise. The only downside with a single bevel, is that it eliminates the option of using a surface treatment such a bluing. I may try for a deep parkerization treatment anyway just to protect the blade a bit. In Al Stohlman's book on tools, he mentions cutting off the end of the knife to make it the right size. So I probably need to trim the tang close to the minimum to give options.

To sharpen with a straight bevel, all the way to the tang, this will result in a fairly fine angle. So my guess is that a well tuned head knife has an angle of 7 to 15 degrees and while the blade is thin, the tang is fairly thick. I think I will aim for 12 degrees on my first one and see how well that does.

Bob

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Bob,

I hope you will let us know how everything comes out. I'm fascinated and can't wait to see the finished product.

As far as full tangs go, I'm an advocate, however I recognize that one design will not suit everybody.

With regard to handle sizes and shapes, I have a J Cook knife that has the curved "Chan Geer" handle on it and I really like the handle a lot. That is something you might want to consider also.

Bob

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For blade geometry, you have a couple of considerations that I'm sure you've thought of, but I'll list them anyway (in case someone else wants to make one).

A single bevel, aka flat grind, has the advantage of being able to replicate the angle during sharpening. All one has to do is lay the bevel flat on a sharpening surface and presto, it's matched. The downside of this is that if your bevel is too thin, you can roll the edge (as afore mentioned).

Several bevels gives a little more strength, but the user risks destroying those bevels while sharpening if jigs aren't used.

Then there's the convex 'bevel'. Bill Moran used this to the extent that it was dubbed the "Moran Edge". It is essentially the most durable way to keep a tough, yet incredibly sharp edge because it keeps more steel behind the edge to support it. Bill Moran used a technique called "slack belt sharpening", but as innovative as he was, he didn't create the process. The 'original' convex edge was used on katanas and other medieval weaponry of that era. It's also commonly found on straight razors. Think about it- When stropping a razor on a leather strap, the strap is seldom held perfectly flat (as opposed to methods for stropping swivel knives). The result is that the edge gets rounded, or convex, as it's stropped and polished, because the belt gives a little as pressure is applied. I've had a little limited success doing it by hand, but the sure way to do it is with the 'slack belt' that Bill Moran described.

Set up a belt sander with a little less tension than it should have, and it lets you curve the belt around the edge your sanding. You hold the knife at a fairly acute angle, then press the side of the edge into the belt. You can pretty easily set up a jig or at least a gauge to indicate how much pressure you're putting on the blade. The more acute the angle, the thinner the convex cross section. Just remember to sharpen AWAY from the edge..... You can go through a few grits on the belt this way, and I think it'd be best to finish with a worn belt embedded with rouge to get a burr free polished edge. It's also pretty dang easy to keep sharp because all you need is a strap of rouge loaded leather hanging near your work.

Hope that helps, and I'll be happy to elaborate if anyone needs it.

Also, I like the idea of a full tang, but would recommend at the very least adding a radius to the butt, so that it's palm friendly.

Edited by TwinOaks

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Mike gave you some good information on Moran's method but I would have assumed like he did that since you were already doing knives that you already knew of the method from the various forums and many internet sites that carry information about it.

However I am going to have to disagree partly with him and Bob on the full tang. Full tangs are great if you already know the size and length of handle for the person involved. I made the same mistake with the first designs that I made for round/head and half round//head knives. I have seen handle lengths differ as much as 1" to 1.5" when people properly fit them to their hands. With a full tang it becomes a little difficult for people to remove the length whereas with a wooden only handle it is much easier to modify to fit. This was the same argument and criticism that the knife makers gave me when critiquing my designs.

If you make a completely custom handle then a full tang custom fit to their hand would be fine but when you are making it for multiple customer delivery then I wouldn't use a full tang. Just my thoughts and some thoughts provided to me from other round knife makers. I still think that it was sage design advice but everyone has different preferences.

Regards,

Ben

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Thank you, this has been a good wealth of information. My intention now is to shorten the back of the tang to go just a bit past the last drill hole, but make the grip much longer so that I can adjust it down to the best line. I will use Chicago Bolts to hold the grip on, so If I go too far on my cutting down the handle, It will be easy to put a new one on.

I may try making one with a dubbed bevel, just for the education, but I may end up grinding it flat. Flat bevels are easier to hand sharpen.

I will be sure to keep posting my progress and mistakes here.

Bob

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