Trad Gang
Main Boards => PowWow => Topic started by: ChuckC on August 21, 2014, 12:17:00 PM
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It is that time of the year. I really would like for this to be a discussion and not a means to raise blood pressures or cause name calling.
What is sharp enough ? and what does getting a blade that sharp do to the blade integrity itself. A real question for me. . if you need to use "almost no pressure" on the head for the final passes on a stone, or file, or burnishing rod (ceramic or other), what does that tell me about the possible integrity of the edge when it smacks into the side of a deer at 160 - 200 fps ?
We all say "scary sharp" but really. . what the heck is that ?
ChuckC :campfire: :campfire:
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I think about this a lot. and I don't know if I ever get it right, but when I use a 2 blade head, I get em sharp. easily shave anyway. but when I use a 3 blade (which I do primarily), I do the method that I learned when I shot wheels with montecs, where I basically sharpen two of the blades at once on a stone. makes it a much greater angle. they come out sharp, and will shave, but hair doesn't fly off as it does with the angle I use on a 2 blade. but, the blade is much thicker and id presume stronger? I don't know, but I do know that my performance, penetration wise, has been pretty much equal with both. and the 3 blades are sooo strong...
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I think it is a worthy question. I have my observations from using files and diamond hones. Last year my wife shot two Bear heads through a buck. One was honed and stropped and absolutely shaving sharp, the other was one that was test fired into a bail, which was resharpened with a Grizzly file. There could have been different contacts on the hits, certainly, but the one that was smooth was quite dull after the hit and the one that I had resharpened with a file was still very sharp. Using my own custom single bevel Hills with either honed or filed edges, I have not seen any difference in the penetration or blood trails. Some broadheads simply do better with razor smooth and razor sharp, while others seem to like files better. I think that it is differences in the hardness or the metal compound itself. Quite often I go with a razor smooth and sharp head and then put a light serration with the corner of a Grizzly file, which has an abrupt end to the file teeth and a rounded smooth narrow side. Even with that option, I wonder if a head shape like a Hill versus a head shape like a Deadhead would have an effect on the effectiveness of the serration. I have noticed one definite difference, a single bevel Hill puts more blood on the ground quicker than a standard Hill, no matter how it is sharpened.
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My assumption has always been that if I can shave hair easily with my broadhead it will do what a broadhead is meant to so and that is to cut.
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I found that not all hair is created equal. I was depressed when I couldn't get my heads shaving sharp. Even sold woodsman elites cause "any idiot" can sharpen a 3 blade, but I couldn't. Then I met the guys on here at the Ohio trad hunt and found out my heads were super sharp according to all in camp, yet they wouldn't shave the hair on my arms. I learned the hair shaving test is not a great test for everybody.
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A fine razor edge that can pop hairs off may dull quickly if anything rubs on the edge. A simple "working edge" like on a pocket knife, that will cut cordage and card board well but may not shave hair is a more durable edge. That's what I try to get with a file edge. Something you don't want to run your thumb down the edge but just not going to shave with. At 160fps, THAT is going to cut lungs, heart, liver, etc. A file edge or Accusharp tool will do the same thing. Try the rubber band test. If it slices them on the first pass. then you're good. To me, Scary sharp is something you dont even want to get your finger near it because it will separate skin with very little effort.
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I usually finish my heads on a hone steel that makes them shaving sharp. I had a friend that always put a serrated edge on his heads with the edge of a file. Someone after checking the edge on one of his heads said, "It's not shaving sharp" to which he said to him, "I don't wanna shave em I just wanna kill em" :D
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Personally I sharpen mine the same way I sharpen my knives and keep them as sharp. I believe cutting paper is the most accurate way to determine sharpness. Shaving hair doesn't always work because a beefier edge may cut paper but the angle won't shave hair. To cleanly cut paper is a sharp edge and sharp enough for hunting.
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I appreciate your comment on scary sharp...that has always made me laugh. It is either a dumb expression or there are a lot of easily scared folks out there. :-)
Having said that, I have enjoyed the journey of learning how to get things sharp. I am still on the journey, but I can get things sharp.
I think the thing that matters more than we think and is the hardest to know without building the knife or BH yourself is the quality of the metal.
The sharpest edge I ever put on a knife was a custom knife a buddy got from a very amateur knife maker. The general quality of craftsmanship was poor, but whatever metal he used was amazing. It was not scary sharp, but it was wow sharp when I got done and I didn't do anything special.
Back to your question, I would guess BH metal is generally ok (some poor and many very good) but I am beginning believe that even with one manufacturer the quality of metal varies a bit from head to head and thus some heads are sharper and, to your point, stay sharper than others.
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Many of us have been doing this for a long time and already have our own ideas of what is needed and what is "sharp enough", but there are a lot of folks just starting out, or just switching to resharpenable heads that really don't know but really want to.
Obviously we want you to learn to sharpen a knife and broadhead. It is one of our talents as a trad bowhunter. We want you to use a good sharp head on the deer, for a lot of reasons, including penetration, good cutting, quick kills and, very important, to give us adequate blood trails to find the critter.
But the term "scary sharp" could mean a lot of things. Put a butter knife in my wife's hands when I piss her off good and that thing is suddenly scary sharp, especially when her eyes dip down below belt level.
Realistically speaking, not everybody can get a broadhead sharp enough to easily shave with, especially a three blade head, but I am asking opinions on whether that is actually necessary.
Can it be not quite shaving sharp and still be adequate ?
CHuckC
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What simulates veins and arteries better than small rubber bands? What cuts rubber bands best? A serrated or file edge will cut more rubber bands than a scarey razor edge.
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I can add that a filed edge may be rough, but still not keen. The trick with a file is to stroke with machine like precision. Since you bring up those that are new to sharpening, I have see that most when first tying to sharpen with a file or a hand held diamond hone make a rounded stroke and get a rounded edge. An arrow holder is better for some to keep the arrow stable while filing or stroking with a diamond hone. If in doubt a KME knife sharpener will get the job done. Fergusson likes to leave a bit of grab on the edge, that is also what a keen serrated edge does. An artery is a stringy thing made of muscle fiber, it is tougher and it moves. While I have no doubts that a razor edge will cut them, but what if that edge skidded off a rib first. As John Schulz stated "I don't what to shave them, I want to kill them." The edge must have that artery cutting edge left after bone contact, it may very well be the serrated edge in softer metal broadheads is better.
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Ron.....I may know who your friend was! Love that quote!
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"Scary Sharp" is a term as I know it to be, that one is scared to touch as they are most likely to get cut.
Now with that said my uncle use to hunt with dull broadheads. He'd practice in the dirt bank and then clean and go hunting.
He swore by the point that the KE energy would stretch the skin more with a dull blade/point, but eventually cut...making a much larger wound cavity.
With that said I saw some deer he shot and they looked like slug holes, but Im not recommending that.
But he was not shooting trad equipment.Xbow
Again depending on the critter, it doesnt take much to get to the vitals.
Lung tissue is delicate, so is liver tissue.
I like my BH able to pop hair on my arm.
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If it makes your eyes bleed when you look at the edge, then it's sharp enough.
Personally, I sharpen mine until they shave hair off of my arm. That's always been good enough for me.
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As a tool maker for 38 years I know when I cut myself on a burr on a work piece I would bleed like a stuck hog. I tend to leave that last little burr and just strop a bit. Fred Bear liked a filed edge which I know had a bit of a burr. It worked for him.....lol!
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The first thing that should be made known about this is that not all broadheads and steels used in them are the same. Generally a softer steel or broadhead utilizing it like the old Razorheads will dull easier if the edge is truly honed to a final smooth shaving sharp edge either on leather or a fine grit stone. Those type of steels and broadheads are best used with a file sharpened edge. The original Woodsman is a good example of this. When I use my Woodsmans I file sharpen them and then use a medium grit stone 600 grit and make a very few passes just to remove any burrs left not to necessarily "hone" the edge. When I am using my Zwickeys or Simmons sharks I almost always start of file sharpening them to get the angle correct and then progressively go through a series of rough to smooth stone ending with a 1,000 grit stone. Both the simmons and the zwickey have harder steel according to the rockwell rating than the woodsman or bear razorhead. If one needs to prove though which edge causes more blood loss than feel free to nick yourself with a brand new razor and then do the same with an older razor that is still sharp and will cut hair but not truly shaving sharp. The smooth honed edge is the most effecient cut, regardless of what type of tissue is being cut. It just depends if your broadhead or knife has good enough (which most do) or hard enough steel (some do and some don't) to support the honed shaving sharp edge. I am not super fixated on either type of edge though as both have been proven time and time again over the course of time. Also let me say this, if an animal is shot through the lungs with a sharp broadhead regardless of it being file sharpened or honed there is going to be a lot of blood for the most part. Find what works best for your broadheads and for you and feel confident knowing that they are sharp.
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Some good info here.....Ya'll keep it coming!
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Great thread
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"Can it be not quite shaving sharp and still be adequate ?
CHuckC"
I think the answer is probably yes. Whitetails are not thick skinned. A reasonably sharp broadhead will likely penetrate to the vitals without much difficulty. I have no evidence of this firsthand because I happen to like sharpening and I don't stop until the head will shave hair. But seeing how mine don't seem to slow down when they hit the deer, I'd guess something not quite as sharp will still get the job done.
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I use a file only on Ace super express. It takes maybe 3min and they will "Roll" the hair off my calf. I've killed several deer and they will still shave after pass thru shots.
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I use an 8 inch file, and about 3 or 4 strokes with a ceramic crock stick. They will shave hair and they will stay sharp. Takes me about 2 or 3 min per head. Some people like to fuss over sharpening for hours and that's fine, but it want kill em any deader.
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This is a good thread and in my first year with a trad bow and Zwicky Eskilites, i appreciate the input!
I can cut hair with them, from a wet fore arm, and they cut printer paper with ease. I think I will be fine with them….? (0ver 500 grain arrow, 10 grains per pound, 52# and 178fps)
I used a file first, but then bought a sharpener with different stones and the jig to hold the angle and i think that made a big difference.
I like the feel of the rough edge on my finger and almost hate to strop the edge when i feel that…
To strop or not to strop, that is the question!
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I never see anyone ask how smelly they can be and still hunt successfully. The sharper the broad head the better. Razor sharp, to me, is best. Shot a moose with a 3 blade, razor sharp Razorcap. The head broke off part of the big socket covering the heart, took off a chunk of rib, sliced the bottom of the lungs and penetrated the heart only to be stopped on the other side by the offside shoulder. She went a total of three strides before going down and the same broad head took a deer a week or two later. The integrity of the edge could not have been better. In addition, some heads are made with steel that is too soft to maintain a razor edge and some is too hard to get there easily for the average hunter.
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I tested this years ago whrn I noticed something with my knives.
When I sharpened a knife with coarse, the medium, then fine then strop the edge was a sharp edge to be proud of. Then I'd open 3 boxes and cut some tubing and then need to cut string and find myself having to saw the string. Feel the edge and dull.
So I would get the edge back by a coarse, then strop and it would hold up Much longer.
So I did a test with broad heads....
Sharpen 2 heads. One coarse, medium, fine, strop. Other coarse (file), quick light touch on medium, then strop. Both hair shaving sharp.
Rubber bands wrapped around a picture frame. Both cut great with slightly better from ultra fine edge. Then pulled each head across a deer jaw bow 2 times each blade. Then back thru rubber bands. The ultra fine never popped all the way thru a rubber band but half sliced a few. The coarseer one still cut all the way thru every rubber band it contacted.
Doesn't matter if I use files, sandpaper, etc...I stay away from fine and ultra fine but always strop.
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I don't think it matters whether you have a smooth shaving edge or a filed edge. Either is sharp enough, in my opinion. As for an edge being dulled after retrieving it from an animal, no big deal. It only gets shot once before it is re-sharpened. I personally prefer the razor edge since that is the sharpness standard I use on my knives. Some will say that is not a valid comparison since broad heads and knives are used differently. That may be an accurate observation.
My grandfather, a shoe maker his entire working life, preferred a rough edge on heavy harness leather and rawhide, because it breaks the fiber better, allowing the leather to open up when cut. This may actually be a good endorsement for the file edge. Still, I like the smooth edge and enjoy the bald spots on my arms and legs.
Whichever choice is selected, a shot placed in the boiler room will do the job quite well.
Just for sake of curiosity, have any of you guys who take numerous animals yearly, tried both sharpening methods and then compared wound results? This would be interesting to read about.
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When I had a bunch of doe tags, I shot all of the deer with custom single bevel Hills. Some were file sharpened, some were razor sharp, some were razor sharp with a fine serration and some were file sharpened with a heavy serration. I would really like to say that the razor sharp shavers did better, but I could not tell any difference. Quite often I did see that the wound opening was far wider than the broadhead, but I have seen that with other two blade heads as well. The other disturbing thing I found is that the common two blade Eskimo is a very deadly thing, the only reason that I do not use them for myself is I got used to shooting wood arrows that are typically five pounds too stiff and I need 160 grain heads for them to shoot and also get to the arrow weight that I want.
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My tag line below reflects my feeling regarding where one should put their emphasis when preparing for a hunt.
That said, over time I have been on both sides of the sharpness issue. After killing 4 - 7 whitetails each year for over the past decade, I have settled on the method below to sharpen my broadheads. I went away from using the razor sharp edges because I found the cutting edge would roll over and dull when hitting a whitetail doe rib. Often you could run your thumb along the edge after hitting a rib and not worry about cutting it. After going back to file sharpening the edge I found those broadheads that had hit ribs were still sharp enough I will not run my thumb along the edge. Like everybody, I have theories why things should, or shouldn’t work, and am still experimenting with the angle of the edge (A steeper angle is giving me better results on the honed edges). However, in the real world, these are my results, so that why I use the file method. The results of others (as previously expressed) vary from mine. I have had roughly the same amount of arrows pass thru (80% +/-) while using mostly a selfbow, and both type of edges kill the deer.
My belief is the arrow flight at impact has a lot more effect on penetration and getting a pass through then the broadhead or edge used.
As Tim Ott once told me, “dead is dead, the deer don’t much care what broadhead, arrow, or bow, you used”. I would add, or how the broadhead was sharpened.
My favorite method is to file sharpen broadheads is from the back to the tip until the edge is raised, then reverse the direction of the file stroke on both sides of the edge from the tip to the back for two or three strokes. At home I use a 12” single cut mill bastard file with a handle and wear heavy leather gloves; in the field I use a 6” version.
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Originally posted by LB_hntr:
I tested this years ago whrn I noticed something with my knives.
When I sharpened a knife with coarse, the medium, then fine then strop the edge was a sharp edge to be proud of. Then I'd open 3 boxes and cut some tubing and then need to cut string and find myself having to saw the string. Feel the edge and dull.
So I would get the edge back by a coarse, then strop and it would hold up Much longer.
So I did a test with broad heads....
Sharpen 2 heads. One coarse, medium, fine, strop. Other coarse (file), quick light touch on medium, then strop. Both hair shaving sharp.
Rubber bands wrapped around a picture frame. Both cut great with slightly better from ultra fine edge. Then pulled each head across a deer jaw bow 2 times each blade. Then back thru rubber bands. The ultra fine never popped all the way thru a rubber band but half sliced a few. The coarseer one still cut all the way thru every rubber band it contacted.
Doesn't matter if I use files, sandpaper, etc...I stay away from fine and ultra fine but always strop.
I agree completely with Jason on this. I will take a sharp but rougher working edge that is tough and long lasting over a finely honed sharp edge that is weak and easily dulled any day.
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I have friends who do what Ron LeClair said and that's run the corner of a file down the edge of the blade after sharpening for a serrated feel.. I personally like a fine polished edge so I go from a extra fine diamond stone to the Simmons sharpening system with the ceramic rods for a super fine scary sharp edge.
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I think their are as many ideas about broadhead sharpness as their are hunters. I prefer a "scary sharp" as defined by SLICKHEAD . :) "Scary Sharp" is a term as I know it to be, that one is scared to touch as they are most likely to get cut. :help:
Dr. Ed Ashby did do some research on this vary subject. this is what he has to say:
Getting an Edge on Success
By
Dr. Ed Ashby
Every bowhunter is seeking one thing, a successful hit, yet far too few give any consideration to the critical difference the type of cutting edge they have on their broadhead makes between success and failure. Let's look at some facts about your broadhead's cutting edge and how it potentially affects your bowhunting success rate. Let's look first at edge finish.
When all else is equal there's absolutely no question which type of edge finish makes a cut that bleeds the longest and most freely; it's the one made by the thinnest, sharpest, smoothest edge. That's a medical and physiological fact. Why? Because the thinner, sharper and smoother the cutting edge the less disruption there is to the cells lining the inner wall of each blood vessel cut. What does disruption of the blood vessel's inner cell-lining have to do with the rate and degree of bleeding from a cut? Disruption of these cells is what initiates the blood's clotting process, known as coagulation.
Each vessel-lining cell that's disrupted releases the protein prothrombin. As prothrombin comes into contact with the blood's plasma it is converted to the enzyme thrombin. Thrombin acts as a catalyst, converting fibrinogen in the blood into fibrin; the final chemical reaction required for blood coagulation. Coagulation stops or retards the rate of hemorrhaging - exactly what the bowhunter does not want to happen.
The 'rougher' a cutting edge is the more it mangles the tissues, tearing rather than slicing cleanly. That means more vessel-lining cells will be damaged, and the amount of disruption to each damaged cell will be greater. The more cells damaged, and the greater the damage to each cell, the greater the amount of prothrombin released. The more prothrombin released, the more thrombin produced. The more thrombin there is, the more fibrinogen converted to fibrin. The more fibrin produced the shorter the clotting time. The shorter the clotting time, the sooner blood loss decreases and/or stops. The sooner the bleeding subsides, the less the total blood loss.
Here are blood's coagulation steps in a flow chart format.
© 2009, Dr. Ed Ashby 1 All Rights Reserved

 Hemorrhaging Flow Chart
Disruption of the inner lining of vessel wall initiates release of the protein prothrombin
Prothrombin reacts with blood plasma to form the enzyme thrombin
Thrombin catalyzes the conversion of fibrinogen into fibrin
Fibrin attaches to tissue tags at the edge of the cut, sealing the vessel to reduce/stop hemorrhaging
A 532;Note the chart's last step; "Fibrin attaches to tissue tags at the edge of the cut, sealing vessel to reduce/stop hemorrhaging". This is a mechanical step in coagulation, and the type of edge finish on your broadhead has a major impact at this stage of the hemorrhaging cycle too. These 'tags' are near- microscopic loose strands of tissue along the edge of the incision, to which the fibrin readily attaches itself. Just as it damages fewer cells lining the vessel wall, a thin, smoothly honed, truly sharp cutting edge creates fewer tissue-tags along the course of the cut it makes.
Having as few tissue tags as possible is not only important at the point of vessel laceration, it's important along the entire wound channel, from the point of entry to the exit wound. The smoother and more tag-free the entire course of the wound channel, the less 'clogging' of the wound channel that occurs secondary to coagulation. A smooth, tag-free wound channel promotes the free flow of blood throughout the wound, improving the rate and degree of both internal and external bleeding. A smoothly honed and stropped, truly sharp broadhead not only increases the rate, duration and total volume of hemorrhaging it promotes a better blood trail.
The difference in clotting effect between different types of finishes on a 'sharp' edge isn't highly significant when a major (large diameter) vessel is severely lacerated or severed. It does, however, become a very important factor when a large vessel is merely nicked, or when only small-diameter vessels have been severed - such as on a marginal liver, kidney or lung hit. The degree and duration of a freely flowing wound is especially important on a shot hitting only one-lung, and is a huge factor on muscle-tissue or pure gut hits; hits into areas where there are fewer major vessels to sever. Recovering an animal after a 'muscle only' or gut hit is entirely possible,
© 2009, Dr. Ed Ashby 2 All Rights Reserved

especially when the wound channel through the gut, heavy muscle or a large muscle group is lengthy, with many capillaries being severed, but recovery requires that bleeding from the capillaries continue unabated and that careful and correct follow-up procedures be used.
Another, often overlooked wound where the type of edge finish becomes very significant is one through the muscle tissues of the heart. The heart muscle, more so than any other tissue, is designed to seal off wounds to reduce the loss of blood. An edge finish that promotes coagulation merely assists the heart muscle's innate tendency to seal the wound, stopping or retarding the bleeding. As with major blood vessels, the type of edge finish on your broadhead will have little effect on a wound passing through multiple heart chambers, but with a wound that merely nicks a heart chamber, hits only one of the heart's chambers or hits only the muscle of the heart wall, the type of edge finish can have enormous impact on hemorrhage and recovery rates.
As noted above, there isn't a highly significant difference when a major vessel is severed. Clotting alone isn't going to seal that off, but here's another hemorrhaging factor to consider. There is overwhelming medical evidence that a shaft which remains in the wound channel contributes (applies) direct pressure on the wound, reducing the rate of blood loss. This is why first responders are cautioned to never remove a penetrating object from a wound until the patient is in a setting where the increased blood loss that results from the object's removal can be dealt with.
According to research by the Royal Academy of Veterinary Surgeons, when an arrow shaft remains in the wound AND the animal continues to move the pressure between shaft and wound is further increased, additionally retarding blood loss. This is one of the reasons why it is very desirable to get a pass- through shot on as many hits as possible.
The combination of these factors; direct pressure of the shaft on the wound and shortened clotting time created by a sharp but rough, ragged cutting edge; can result in hemorrhagic sealing, or near-sealing, of even substantial wounds; significantly retarding onset of physiologic shock and ensuing collapse. At the best this means a longer blood trail of lesser degree. At the worst it means an animal mortally wounded and not recovered. Even with a pass-through hit, clotting time always becomes a very important recovery-rate factor when only small- diameter vessels have been severed.
© 2009, Dr. Ed Ashby 3 All Rights Reserved
Cut Efficiency
Now let's go back to the very start; "When all else is equal, there's absolutely no question which type of edge finish makes a cut that bleeds the longest and most freely; it's the one made by the thinnest, sharpest, smoothest edge." There are many who contend that 'all else' is not equal; that a ragged, serrated or scalloped edge cuts more tissue than a straight, smooth, sharp edge. The theory expounded is that the irregular edge 'grabs' the tissue, ripping and tearing at it, whereas a smooth edge allows the tissue to move along the edge without being cut. Besides the coagulation factors discussed above there are several flaws to this reasoning. Consider the following.
(1) No one who's ever shaved with one would disagree that a rough-edged razor grabs at both whiskers and tissues, but it certainly doesn't cut whiskers as effectively as a sharp, smoothly honed razor. And there's absolutely no doubt that the rough-edged razor is also going to rip many small chunks of tissue from the face, but all those lacerations together will not shed the volume of blood that comes from a single nick with a truly sharp razor.
As this un-retouched photo shows, with a single pass a smoothly honed and stropped, truly sharp broadhead shaves as cleanly as any straight razor. CAUTION: Never try this unless you are practiced at shaving with a straight razor!
(2) Whenever fibrous tissues, such as skin, tendons, ligaments and fascia are penetrated, testing shows that the irregularities along a roughly-finished edge quickly become clogged with strands of tissue fiber. This clogging is present for "Hill type" serrations, the marks left by file sharpening and micro-serrations left by final sharpening with anything short of an extremely fine-grit steel or stone. In sever cases
© 2009, Dr. Ed Ashby 4 All Rights Reserved

this clogging becomes so extensive that that the edge is rendered incapable of cutting tissue, even when considerable pressure is applied, but even a few strands of clinging fibers markedly reduces cutting effectiveness. And there's more.
Testing different edge finishes on different types of broadheads in fibrous tissue. The target is multiple layers of fresh Asian buffalo skin, 7" thick. Each arrow was shot first with a smooth, honed and stropped edge, then with a smoothly file-sharpened edge and finally with an edge having 'Hill type' serrations. Each arrow's result was compared to its own results with the other edge types. In every case the smooth, honed and stropped edge penetrated deeper, cutting more tissue. Clinging fibers were present on the edge of every file sharpened and serrated edge.
The Asian buffalo skin is extremely fibrous. The smoothly sharpened, honed and stropped edge of my 3" blade Case sheath knife virtually unzipped the hide with little effort. The 'super sharp' scalloped edge of a Spyderco knife required a forceful sawing motion to slice the hide. Try it yourself!
© 2009, Dr. Ed Ashby 5 All Rights Reserved
(3) Testing also shows that a smoothly sharpened, honed and stropped edge, free of all serrations and burrs, penetrates tissues easier than one having a rough edge. On all except pass- through shots that means a longer wound channel for the smooth edge. A longer wound channel means more vessels and capillaries will be encounters by the broadhead, increasing the opportunity to cut vessels.
Next, we have the scalloped edge. An often cited example of a scalloped edge working better than a smooth, non-scalloped edge is serrated steak knives vs. non-serrated ones. There are several reasons why serrated-edge steak knives are widely used, and often seem to cut our mealtime steak with more ease than the straight-edged steak knives commonly encountered. The chief reason is that not many folks have steak knives with high quality steel, and even the few who do (at least among those I've encountered) don't keep them well sharpened. The other factors all revolve around the steak on our plate already being dead, butchered and cooked.
Our dinner steak doesn't have a covering of fibrous skin, and the fibrous connective tissue remaining in the steak has been modified by cooking. As our early ancestors all knew, cooking connective tissue - skin, sinew, tendon, ligament, horn or hoof - softens it. Cook it long enough and it becomes liquid, making good glue.
Slicing tissues requires a sharp edge. If a smooth edge is not sharp it has great difficulty cutting through even soft tissues; it has to tear them, rather than slicing through them. Even when dull, a scalloped, rough or serrated edge has an irregular, abrasive surface. When the edge is dull this makes it easier for the edge to tear at the tissues, but not easier for it to slice tissues.
Crucially, in living tissues there are bones our arrow must cut or break. Arrows can't neatly carve around bones, as we do when eating our steak. Bone is the most difficult tissue your hunting arrow will be called upon to deal with, and bone contact occurs on the vast majority of hits. Bone doesn't cut well with anything short of an offset-tooth saw blade. The thin projections of a scalloped edge are fragile, and easily damaged on hard bone impact. Once damaged they greatly reduce cut effectiveness and markedly increase arrow drag, reducing penetration.
Having serrations on the cutting edge also reduces the broadhead's overall mechanical efficiency; its ability to use whatever amount of force it carries. For elevating a resistance load; which is precisely what a broadhead does as it penetrates; a smooth, gradual inclined plane does the most work with the least applied force. That's why wheel chair ramps are a straight
© 2009, Dr. Ed Ashby 6 All Rights Reserved
incline – and why they don't have 'speed bumps'. If a load could be raised to the same level with less force by using a concave, convex or scalloped-surface wheel chair ramp you can darned well bet they would be made that way!
Have you ever tried field dressing or capeing a big game animal with a scalloped edge knife; even one with a sharp edge? Have you also field dressed or caped one with a knife having a truly sharp, smoothly honed and stropped edge? Is so, you won't need any convincing which edge cuts more efficiently. If your broadhead isn't truly sharp then you're probably better off with a scalloped or serrated edge, but it's a poor, poor substitute for a truly sharp edge.
Need more proof? Drop by any butchery shop, assuming you can still locate one in this day of pre-packaged everything, and see how many scalloped edge knives these folk who make their livelihood slicing through tissues have on hand. Neither scalloped nor serrated edges cut tissues as well as a smooth, sharp edge – but they will tear through tissues better than a dull, smooth edge.
About here someone is going to say, "But the knapped edge of a flint broadhead is a scalloped edge, and has fine serrations all along it, and everyone agrees they 'cut better' than steel broadheads". Few edges cut more efficiently than the ultra-thin edge obtained by removing a flake from flint or obsidian; but one that does can be found on smoothly polished obsidian scalpel blades, which, in pre-laser days, were often used during delicate eye surgery. An obsidian scalpel cuts more cleanly than any steel blade, and cleaner than the finest knapped obsidian edge. Why? Because it's highly polished edge, as thin as that of the finest obsidian flake, has absolutely no serrations. Its cut is fully as smooth and flawless as that of a surgical laser, but the laser's advantages of pinpoint focus and simultaneous cauterization of cut vessels has antiquated the obsidian scalpel.
Broadhead and Edge Design
There are also many features of your broadhead's design that affects the quality of the cut it makes as it passes through the tissues ... aspects few bowhunter's think about, but should. Foremost is the quality of the steel in the blade, and this is the 'cure' for your thin, smoothly honed and stropped edge losing its sharpness before it has finished penetrating the tissues. If your broadhead is truly sharp at impact but no longer truly sharp when it exits then the steel in the blade is not strong enough for the edge bevel you have on the broadhead.
© 2009, Dr. Ed Ashby 7 All Rights Reserved

Softer steels are easier to sharpen, but are not strong enough to resist damage when the edge is thin. At any sharpening angel the cutting edge on softer steel will dull more quickly than were it on harder steel. To compensate for this folks sharpen softer-steel broadheads at a more abrupt angle. This helps with the edge retention but sacrifices the advantages of a thin edge; one sharpened at a lower angle and having a better mechanical advantage. As long as the edge is truly sharp and smooth, why does this matter? It's more than just the thinner edge damaging fewer of the cells lining each vessel's wall.
At equal levels of sharpness, the mechanical advantage of a broadhead's edge bevel affects the quantity of the cut achieved. The lower its total sharpening angle the higher mechanical advantage an edge bevel has. Think of the edge bevel as a simple wedge (if double-beveled) or simple inclined plane (if single- beveled). The longer the bevel's slope in relation to the rise (the blade's thickness) the higher the bevel's mechanical advantage will be.
Having a higher mechanical advantage means an edge can do more 'work' at whatever amount of tension the broadhead creates between the tissues and the edge; and we'll talk more about tissue-to-cutting-edge tension in a moment. Compared to an edge having a lower mechanical advantage, a higher mechanical advantage edge bevel slices equally well at less tissue-tension ... or you could just as well say, at the same level of tension between the tissue and the cutting edge a higher mechanical advantage edge will slice deeper.
Much discussion has been directed towards (overall) broadhead mechanical advantage and the increased penetration- potential offered by long-narrow heads, but such broadheads offer another characteristic worth consideration. The longer a broadhead's cutting edge, the greater the distance tissues travel along the edge. Increased tissue travel-distance along the edge increases contact time, offering the blade greater opportunity to sever the tissues.
To see the difference greater tissue-travel and longer contact time makes, place the edge of a sheet of paper against a sharp blade's edge. Keeping even pressure of paper to blade, push or pull the paper along the blade. The greater distance the paper is moved, the more deeply it is sliced. What you're observing is increased cutting potential resulting from greater travel-distance. With broadheads, a longer length cutting edge increases the likelihood that each blood vessel encountering the edge will be severed. Why the "Keeping even pressure of paper to blade" qualifier? This brings us back to tissue-tension against the cutting edge.
© 2009, Dr. Ed Ashby 8 All Rights Reserved

A broadhead acts as a compound-wedge during penetration. Blade width and thickness, ferrule-taper and edge-bevel all spread tissues at an angle to the blade's edge. This tensions pliable tissues against the edge, making them easier to slice; much as a tensioned rubber band slices more easily than one that's lax. In soft tissues, broadhead rotation induced by a single-bevel design also spreads the tissues, creating additional tissue-tension and increasing cut-efficiency. The rotating single-bevel broadhead also causes tissues to be dragged forcefully across the blade's sharp edge at an angle to the forward motion of the cutting edge.
Having the broadhead rotate as it penetrates not only enhances the slicing effect, it cuts more of the vessels encountered on a bias (obliquely, at an angle). As shown in the illustration, a vessel of equal diameter will have a larger opening in the vessel wall when it's cut on a bias, as opposed to a right-angle cut. This makes it more difficult for coagulation alone to seal the cut, promoting faster and freer bleeding. Yes, blood vessels do travel in all directions and every broadhead will cut many of the vessels encountered at a bias, but having the broadhead rotate greatly increases the mathematical probability of cutting each vessels at a bias – even when initial edge contact with the vessel is perpendicular.
So there you have it, just what every bowhunter seeks; the broadhead edge that works the best. Good quality steel in the broadhead's blade, while requiring more effort to sharpen, allows you to use a thinner edge with higher mechanical advantage while still retaining blade sharpness throughout the entire course of penetration. The high mechanical advantage of the low angle edge-bevel cuts more efficiently at any given level of sharpness and tissue tension. Using a longer length cutting edge increases tissue-to-edge contact time, increasing the slicing effect. A single-bevel edge induces rotation, increasing the degree of tissue tension, dragging tissue forcefully across the edge at an angle to the cutting edge's direction of forward motion and cutting more vessels on a bias,
© 2009, Dr. Ed Ashby 9 All Rights Reserved

inhibiting coagulation and promoting freer bleeding. And last ... but really first and foremost ... on any given hit that thin, smoothly finished, truly sharp edge creates a cut that bleeds longer and more freely than any other cutting edge.
Nothing ... absolutely nothing ... does more for success than fast collapse time and, except for nerve center and locomotion disabling hits, fast collapse time depends on the rate of blood loss. Giving your broadhead an edge for success not only yields faster collapse, better blood trails and shorter recoveries on those fanciful 'perfect hits', it gives an enormous advantage whenever your hit is less than perfect. And it doesn't hurt to enhance the penetration potential of your arrow setup, improving your odds for a total pass-through hit. You don't want that arrow shaft hanging around in the wound channel an longer than absolutely necessary. Preventing shaft pressure on the wound will make the most of the advantages you've just gained from your broadhead's newly optimized cutting edge ... and each gives you an edge on success.
© 2009, Dr. Ed Ashby 10 All Rights Reserved
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Although technically correct, the above won't even start to happen if the critter dies in a minute. A hole thru the diphragm, thru both lungs, thru the core of the heart, all will cause other major disruptions, whether the "stick" is even sharp or not.
Add a sharp edge or two so you cut blood vessels and not just poke a hole and it gets even better. Push that sharp edge thru the tissue at speeds of 160 - 190 fps (trad gear speeds) and you cut more with even a moderately sharp edge.
No doubt about it, a sharp head is our goal and is better. It certainly aids when a less than perfect hit requires bleeding out and in terms of being able to blood trail the critter.
ChuckC
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CHUCK YOU ARE RIGHT ON.. WE DO ALOT OF THINGS TO MAKE OUR SET UPS THE BEST WHICH MEANS PREPARING FOR THE WORST……. " STUFF HAPPENS " …..IT HAS BEEN MY EXPERIENCE IT ALWAYS DOES SOONER THAN LATER AT LEAST TO ME :goldtooth:
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Me too. I agree with most everything especially sharp heads. I have seen first hand how a sharp head saved the day on a less than stellar hit.
I worry that in our zealousness we say some things that others with less experience take and run with. They need to understand the "why" and not just the "do it" so that they can make the right choices for themselves.
That was the whole purpose of my asking for this discussion, so that they can hear why and how to achieve it (and in the case of "scary sharp", what that might mean).
ChuckC
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Been sharpening things for close to 50 years now. Seen lots of "sharp" knives and broadheads. Mostly, they really weren't sharp at all. If your knife dulls after a couple cuts of cardboard, you either haven't sharpened it properly or the steel isn't very good. Not being snotty or anything. Not putting anyone down. If a razor sharp knife wasn't capable of standing up to vigorous use, woodcarvers and wood workers wouldn't use them.
I do believe tho, some broadheads (Bear razorheads, my favorite) don't have the proper metal to hold a razor edge.In that case I would think a filed edge would be best.
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The sharper the better! When the BH pops dry hair I'm done.
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I am not the greatest sharpener but they get the job done.
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Respect for the game we hunt must be the driving reason behind everything we do in the field.
And because we are dealing with many variables we cannot control we should work fastidiously in any area where we are able to exert control.
Broadheads and how sharp they are is one of the most critical- not for when you do things perfectly- but for when you don't.
That unseen twig that deflects your arrow in low light- the ticking of a rib bone on entrance and the arrow being pushed off target, or the single step forward as we release which turns a great shot into a "not so great" shot.
A thousand things really, that can happen during that short interval between relaxing fingers on the string and the striking of a critter.
Ed Ashby's extreme testing is spot on- one of the arguments I always hear is " but I'm not hunting cape buffalo". The reason large animals were Ed's test platform is because at the extremes is where you see differences in results more easily.
Believe me, a direct hit on a shoulder knuckle of a mature whitetail will provide some dramatic results- good or bad- depending on the choices you make.
You prepare for the worst-then diligently work to do your best in every situation. When the worst happens, and it will- or you simply lose concentration because a gnat flies in your eye at the moment of release - the sharpness of that head COULD be the thing that saves you from a wounding loss.
Someone once told me a long time ago- successful bowhunting is the elimination of all errors. But we can't do that because we aren't in control of EVERYTHING. So control those thins you can.
I ran a very successful hunting operation for several years- doing that you encounter a broad spectrum of hunters with varied levels of skill in all areas.
One of the areas where guests needed assistance most often was getting broadheads really, really sharp.
One other area we don't discuss much is steel- you simply can't sharpen steel that has not been handled correctly by the maker- the heat treating process either makes a product that will get and hold an edge or it doesn't. That's where research on your part is critical.
That's why I do not like machine sharpening- a heat treated head can be quickly ruined by overheating when using belt sanders, wheels, etc and then you're really in trouble. You also can't carry those items in the field, typically.
Learning to sharpen with file and hone so you can carry that skill into the field might save a hunt. You can't bring electricity into the mountains on an elk hunt, right?
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Right On Target Ray! :thumbsup:
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Great discussions and inputs. As always civil discourse and discussion leads to the greatest learning for all. Thanks for all the ideas and explanations here.
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I have a reloading bench I built years ago so I could stand up and work the press. This bench has several 2x10's for the top. The top comes up to the bottom of my rib cage when I'm standing.
I lay the arrow with the broadhead attached on the edge of this bench. I position the broadhead so the edge is parallel to the bench top. With my thumb holding down the opposite edge down on the bench top I'm able to file the other edge. Since I have the edge parallel to the bench top it also makes it easy to file parallel to the bench top so I can maintain the same bevel..
Like the other guys, I have used just filed heads, honed heads, stropped heads and everything inbetween.. Put 'em in the right place and they will kill reliably..