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Jeremy V. Krause




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PostPosted: Fri 07 Apr, 2006 5:46 pm    Post subject: question regarding sharpness         Reply with quote

Hello everyone,

Let me begin this post with an admision that I am a bit OCD when it comes to the sharpness of my swords. That being said here is the sittuation. I only use my swords for dry handling and it seems to me that my swords have become less sharp over time seince I received them from the manufacturer though I have never cut with them. I test blade sharpness with my nail and I desire a more or less paper cutting edge.

The only thing I can ascribe this reduction in the edge sharpness is possibly my oiling of the blade. I fun a oil impregnated sock along the edge so it my sort of "bunch" and rub along the edge. Could this over time- oiled once or twice a week, slightly dull the edge. Or should I bring this issue to a sword mental health professional. Wink Confused

Is there a way I could restore the sword edge or should this be done by the maker? Incidently, I will continue to work on my fixation as I know a sword does not have to be "that" sharp.

Thanks,
Jeremy
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Lancelot Chan
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PostPosted: Fri 07 Apr, 2006 11:23 pm    Post subject:         Reply with quote

Could be the sock, or the scabbard you keep the sword in that dulled the edge. Well, some swords were as sharp as paper cutting. Wink I tend to keep all my swords that way. You may restore the sharpness yourself if you know how, but usually the polish around the edge area will become different. I don't mind about that so I do this myself with a DMT diamond hone.
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Geoff Wood




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PostPosted: Sat 08 Apr, 2006 2:13 am    Post subject: Re: question regarding sharpness         Reply with quote

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Last edited by Geoff Wood on Thu 20 Apr, 2006 11:54 am; edited 1 time in total
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Peter Johnsson
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PostPosted: Sat 08 Apr, 2006 2:26 am    Post subject:         Reply with quote

The most acute biting sharpness of the edge of a carbon steel tool or weapon is dulled by fingering after some time. Some people are actually more harmful than others: it depend on the personal mix of your hand sweat. Some people have fingerprints that eat away steel like ferric chloride.
I notice this clearly after demos, when each and every person who gets to hold a sword simply must feel the edge and go: Ohhh! It is a tempation that is too great to resist, regardless if you kindly ask them to please not touch the blade. They just *have* to test the sharpness with a gingerly applied finger.
Some people need only touch a blade once and you get a nice rust print.

After the session, my swords are not so sharp any more, but need a rehoning or a touch up with a leather strop. Their edges are still sharp enough to cut effecitvely, but does not have that popping sharpness.

It should be nopted: this degree of sharpness is not strictly necessary, but can be fun. It depends on what and how you want to cut with your swords. And how much you enjoy maintenance.
If you enjoy this kind of hair popping shaprness, it is adviceable to aquire the skill of honing and stropping.

I need perhaps stress that we are talking about that last crazy degree of sharpness that a sword will have as it is just stropped. How long that kind of sharpness will last is totally dependent on what and how you cut.
If you cut paper with your swords, they will also get dull after a while. Never so dull they will not delvier completley effective cuts, but they will loose that acute popping sharpness. Paper can be rather abrasive actually. Fingerprints along the actual edge is usually the cause for most "dulling" however.

Ask any professional chef or cabinet maker that care about their tools (who use traditional carbon steel tools): they will tell you that you are not supposed to touch the edge of a sharp chisel or knife. That is detrimental to the most acute sharpness.
All afficionadoes of Japanese swords are well aware of this: never touch a naked blade! That is mostly because of th high level of polish of the presentation grade japanese blades but it can have an effect on the edge as well.
In practical/functional terms it is the finely honed edge that is most vulnerable.

A sword that is much less sharp than this will still deliver absolutely effective cuts however.

If you want your swords to keep their absolute keen edge keep fingers away from the blade.
I know myself that can be difficult as the finely honed sharpness is a special joy to feel...

A matter of self control.
Wink
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Jeremy V. Krause




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PostPosted: Sat 08 Apr, 2006 10:20 pm    Post subject:         Reply with quote

Thanks everyone for your replies,

Peter, regarding the use of a leather strop- should I use the shaving razor type and if so should I glue it to a piece of wood. Aren't these strops two sided? What type of honing tool would you recommend? Is there a perferred angle to use the strop?

Also I am reticent to even attempt to sharpen my swords because I do not want any kind of secondary bevel to form. I have sent my swords back to the maker in the past but this is a pain and I want to develop the skill to maintain my own edges.

Gosh! if this were only as easy as it is for my A&A danish axe! Confused

Thanks again everyone.
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Lance K.




PostPosted: Sun 09 Apr, 2006 1:04 am    Post subject:         Reply with quote

I have found that polishing my sword is the main reason it has lost some of its edge. I first started noticing it back when I would clean and polish it with a cloth and polishing cream. Now that I use oil with steel wool or scotchbrite the difference is more accelerated.
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Jeremy V. Krause




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PostPosted: Mon 10 Apr, 2006 5:50 pm    Post subject:         Reply with quote

Actually this is a bit of a bump as I believe others must have insight related to this issue,

So has anyone else noticed a very gradual dulling of their blades due to normal oiling and polishing? How or do you maintain an optimal (sword, non secondary-bevel) edge.

Thanks,
Jeremy
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Addison C. de Lisle




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PostPosted: Wed 19 Apr, 2006 7:14 am    Post subject:         Reply with quote

Well, I'm nowhere near as experienced as others who have replied to this topic, but while making my (first) knife with stock removal, I noticed that the edge I put on with my files was dulled after I polished the whole thing with very fine grit sand paper. Nothing a few seconds with a fine file couldn't fix. However, since this is untempered steel my observation may not apply.

Also, is it really necessary to polish and oil your sword once a week, or is it that you cut with it every week so it requires re-polishing and sharpening?
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Jeremy V. Krause




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PostPosted: Wed 19 Apr, 2006 1:51 pm    Post subject:         Reply with quote

Hello Addison,
I only oil my swords about once a week usually after I handle them- I do not polish them unless I notice a mark of some kind. I have read that one should oil their swords even if they do not touch the blade. I live in a rather labile climate and also like to ensure that no stains or pits are formed by dust collecting on the blade.
I choose not to use a file and/or stone to sharpen my swords as I do not want to form a secondary bevel like that found on knives. I do not believe that I have the skill to sharpen my swords without forming a secondary bevel.
This is why I have posted- to determine how others keep their swords sharp while maintaining a proper edge. Or indeed if others worry about establishing a secondary bevel on their high end swords.

Jeremy
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James A. Vargscarr




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PostPosted: Wed 19 Apr, 2006 6:13 pm    Post subject:         Reply with quote

I have never needed to oil/polish my blades often and I'm not a regular cutter, but even those swords I've owned for years have shown no signs of dulling. Do you rub the edge in a particularly abrasive way? A good coating of whatever you use is all in needs.

If you want to oil or polish your swords less, I would recommend picking up a Tuf Cloth (http://www.sentrysolutions.com/TufClothkew.shtml). I made the switch from Silicone polishing cloth about eight months ago, and I couldn't be happier with it. The Silicone was great for long term protection and I found it much cleaner than oil, but it left a moist film on the blade much like oil does. With my Marine Tuf Cloth, I wipe down the blade and fittings; leave them a minute or so, and then give them a rub down with a dry cloth. The sword looks and feels as though nothing is there, but the rust protection is much longer lasting than an application of regular oil, with no need for frequent reapplications. The steel also looks stunning - I hadn't realised how the coat of silicone had dulled its lustre. It's been so long I forget if coatings of oil had the same effect; but the Tuf Cloth coating brought out a beauty in the finish of my swords I never knew was there. I opted for the extra protection of Marine Tuf Cloth, but the regular Tuf Cloth I've linked should be more than sufficient, and that wipes on and dries clean without the need of a second rub down.
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Jean Thibodeau




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PostPosted: Wed 19 Apr, 2006 6:18 pm    Post subject:         Reply with quote

I don't use my swords for any serious cutting so the need to sharpen is minimal after just test cutting the occasional piece of paper or minor dulling due to casual handling so my sharpening of my swords is done very very lightly.

A secondary bevel I can only see with an 8X loupe I don't worry about too much and since I got over my obsession with making everything razor sharp I don't go nuts re-sharpening every time I look too hard at my swords' edges.

Now sharpening, creating no secondary bevels. means taking material off the entire main bevel to sharpen an edge. Eek!

Hard to do perfectly when making a sword and even harder to maintain if re-sharpening. If I'm not mistaken Japanese swords are made and maintained this way since repolishing and sharpening are done as one process. ( Although there is no obvious secondary bevel there may be a very subtle apple seed convex final edge even with Japanese swords. )

Again I could be wrong, but European swords when new have a " small " secondary bevel but it is rounded and blended in so that it does not appear on the edge as a distinct bevel. So one would remove as little metal as possible when
re-sharpening and give it a convex apple seed profile. I think there are techniques to do this using an abrasive glued to a soft backing surface and sharpening by rubbing away from the edge.

Me, I just use a smooth steel to burnish the edge or a white ceramic hone very lightly to get or restore a paper cutting edge.

Again, a secondary bevel I can only see with my 8X loupe and not some 1/4" wide secondary bevel.

If I got any technical aspects wrong please feel free to correct me as I am not an expert sharpening swords but I can and do get that razor sharp hair popping edge when sharpening knives.

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Jeff Smith




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PostPosted: Wed 19 Apr, 2006 8:49 pm    Post subject:         Reply with quote

Ref the MARINE TUFCLOTH...

Thanks for the tip! I just ordered a 2-pack of these for maintaining my Albion Crecy:)
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Angus Trim




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PostPosted: Wed 19 Apr, 2006 10:31 pm    Post subject:         Reply with quote

Jean Thibodeau wrote:


Again I could be wrong, but European swords when new have a " small " secondary bevel but it is rounded and blended in so that it does not appear on the edge as a distinct bevel. So one would remove as little metal as possible when
re-sharpening and give it a convex apple seed profile. I think there are techniques to do this using an abrasive glued to a soft backing surface and sharpening by rubbing away from the edge.

Me, I just use a smooth steel to burnish the edge or a white ceramic hone very lightly to get or restore a paper cutting edge.

Again, a secondary bevel I can only see with my 8X loupe and not some 1/4" wide secondary bevel.

If I got any technical aspects wrong please feel free to correct me as I am not an expert sharpening swords but I can and do get that razor sharp hair popping edge when sharpening knives.


No you're not wrong Jean, there is indeed a secondary bevel on most Euro swords, and all of the "production" euro reproductions out there......... the most expensive are blended in real well, and the blend may have a name like "appleseed", but its still a different angle right at the cutting edge than the main bevel, so yes, its a secondary bevel no matter what its called.......

swords are fun
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Angus Trim




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PostPosted: Wed 19 Apr, 2006 10:41 pm    Post subject: Re: question regarding sharpness         Reply with quote

Jeremy V. Krause wrote:
Hello everyone,

Let me begin this post with an admision that I am a bit OCD when it comes to the sharpness of my swords. That being said here is the sittuation. I only use my swords for dry handling and it seems to me that my swords have become less sharp over time seince I received them from the manufacturer though I have never cut with them. I test blade sharpness with my nail and I desire a more or less paper cutting edge.

The only thing I can ascribe this reduction in the edge sharpness is possibly my oiling of the blade. I fun a oil impregnated sock along the edge so it my sort of "bunch" and rub along the edge. Could this over time- oiled once or twice a week, slightly dull the edge. Or should I bring this issue to a sword mental health professional. Wink Confused

Is there a way I could restore the sword edge or should this be done by the maker? Incidently, I will continue to work on my fixation as I know a sword does not have to be "that" sharp.

Thanks,
Jeremy


Hi Jeremy

The secondary bevel is already there, even if the majority of it is a "radius" from the main bevel. Sharpening that will be tricky if you don't want to make an obvious "secondary bevel".

The thing to do though is to get a flat diamond hone, fine. Lay the hone right on the "flat" of the edge, the very cutting edge angle. Carefully slide it lenghwise on the edge. Do this on both sides lengthwise, the length of the edge. Once sharp, inspect to see how much you've changed the finish. Since I think we're talking Albion here, the thing to do next is to use a scotch brite pad right on the same path you just used the hone, and lengthwise reestablish the satiny finish.........

The trick is to do this without dulling the edge again......*g*

The thing about a cutting edge is, that the sharper it is right at the edge, the easier it is for the edge to disapear. And the odd thing is, it doesn't take much. A little bit of the oils from our hands..... just wiping the edge with oil.....

Cleaning with scotchbrite is a real killer.........

This can be done Jeremy, I've recently done it for a customer of mine on his Albion...... pretty much the way I described it.

However, if you don't have sharpening experience, still want to do this yourself, I'd practice on something else first, something like a WS product. Something fairly soft and easy to work with first.......

swords are fun
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James A. Vargscarr




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PostPosted: Thu 20 Apr, 2006 4:38 am    Post subject:         Reply with quote

Angus Trim wrote:

No you're not wrong Jean, there is indeed a secondary bevel on most Euro swords, and all of the "production" euro reproductions out there......... the most expensive are blended in real well, and the blend may have a name like "appleseed", but its still a different angle right at the cutting edge than the main bevel, so yes, its a secondary bevel no matter what its called.......


I might be way off the mark here, but I thought that every sword - no matter its origin - technically had a 'secondary bevel'; in the sense you describe the term above. My impression was that since the cutting edge needs to be of such drastic acuteness as compared to the rest of the blade's cross-sectional geometry, it is always going to be filed on as a secondary bevel before the final stage of polishing. That said, I'd also considered a high quality polish which seamlessly blends the cutting edge into an appleseed geometry to have fulfilled the task of completely negating that secondary bevel - turning the angle into a curve so that the term no longer applies.

Are you saying that no European sword truly achieves this negation of the secondary bevel on a microscopic level; and if so, is your implication that Japanese swords do? I'd always thought the extreme depth of Japanese sword polishing techniques were mainly focused on bringing out the activities in the steel; and though the Japanese polish obviously serves the purpose of final edge shaping as well, I hadn't considered the difference in quality between an appleseed edge on a Euro sword and the bevel of a traditional Japanese sword to be so great.

Jeff Smith wrote:

Ref the MARINE TUFCLOTH...

Thanks for the tip! I just ordered a 2-pack of these for maintaining my Albion Crecy:)


I hope you find them as impressive as I did! I believe Christian Fletcher used to bundle a Tuf Cloth in with the swords he sold at one time - perhaps he still does. Most people on the boards are long time sword collectors with tried and tested oiling preferences, but I always wish silicone and Tuf Cloths got more press. Their coatings never evaporate, they make storing swords in leather scabbards viable in the long term, and the more obsessive can never apply too much at the risk of trapping dust particles, as one can with oil.

I see we're of a like mind in choosing Marine Tuf Cloth over the regular - I'll always pay a couple of bucks more for protection overkill too. Just remember you need to polish off the excess to a full shine after applications, otherwise your sword will feel very gunky! I waited a night for the stuff to dry before I read the footnote stating that Marine grade needs a final rub down with a clean cloth, unlike the disappearing coat of the regular grade. I feel like I can treat my swords like stainless steel now. Not that I touch the blades much, but I like handling guards and pommels without getting oily and knowing they won't rust at the contact. Wonderful product.
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Angus Trim




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PostPosted: Thu 20 Apr, 2006 3:06 pm    Post subject:         Reply with quote

James A. Vargscarr wrote:
Angus Trim wrote:

No you're not wrong Jean, there is indeed a secondary bevel on most Euro swords, and all of the "production" euro reproductions out there......... the most expensive are blended in real well, and the blend may have a name like "appleseed", but its still a different angle right at the cutting edge than the main bevel, so yes, its a secondary bevel no matter what its called.......


I might be way off the mark here, but I thought that every sword - no matter its origin - technically had a 'secondary bevel'; in the sense you describe the term above. My impression was that since the cutting edge needs to be of such drastic acuteness as compared to the rest of the blade's cross-sectional geometry, it is always going to be filed on as a secondary bevel before the final stage of polishing. That said, I'd also considered a high quality polish which seamlessly blends the cutting edge into an appleseed geometry to have fulfilled the task of completely negating that secondary bevel - turning the angle into a curve so that the term no longer applies.

Are you saying that no European sword truly achieves this negation of the secondary bevel on a microscopic level; and if so, is your implication that Japanese swords do? I'd always thought the extreme depth of Japanese sword polishing techniques were mainly focused on bringing out the activities in the steel; and though the Japanese polish obviously serves the purpose of final edge shaping as well, I hadn't considered the difference in quality between an appleseed edge on a Euro sword and the bevel of a traditional Japanese sword to be so great.



Hi James

I think what I said was "most" euro swords, in fact that is what I did say...... I've seen one, an early 18th century teastrainer that the main bevels are flat right to the edge, forming the edge. But the blade is narrow in width, and thick in crossection. Thus, it has a fairly robust edge. I haven't seen any earlier pieces that way, but in discussions with Craig Johnson, he tells me that he has seen a few earlier pieces where there is a very fine edge, so I do believe that it is possible that earlier swords, particularly earlier cutting swords could have that fine an edge..........at least until it gets used once......

The more delicate the edge, the less use it will stand without major repair......

On the kat edges, the whole bevel is convex to a certain degree, its what they call "niku". Typically, the blade is thick at the ridgeline, with a convex shape to the edge, thus the edge can be both sharp and robust.......

I've seen three antique gian with flat main bevels forming the edge. The edge is extremely fine, but I think these swords would have been meant for finesse work, the edges were too fine to traverse thru bone without some damage in my opinion.........

Any modern euro "reproduction" that is intended for use, and has too fine an edge, is just asking for the kind of negative attention that we've seen over the last year when an edge takes some damage cutting thru meat and bone. Edge geometry is the best way to deal with this, even the hardest edge can deform under enough stress, add a bit of meat behind it, and add to the included angle of the edge, and you make it more durable.......

swords are fun
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James A. Vargscarr




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PostPosted: Thu 20 Apr, 2006 5:07 pm    Post subject:         Reply with quote

I'm with you now - I was equating an appleseed edge with the niku of a katana; but I hadn't taken into account the (in retrospect obvious) differences between the thinner blades of Euro swords overall, and the generally thicker blades of kats that give added strength to the finer edge. It sounds like Japanese edges can be more 'appleseedy'/more convex without resultant weakening of the edge simply because there's more metal to work with, and the thinner cross-sections of Euro blades make totally convex edges less desirable.

I was just confused as to the definition of 'appleseed' and 'secondary bevel'. Of course swords like the antique you described with the flat main bevels to the edge would have no secondary bevel; but I was thinking that more typical swords with a drastic change in gradient at the cutting edge could still have the hard angle removed through polishing - creating the curved appleseed or niku effect - and that this curve qualified the blade as having no secondary bevel because the angle was completely removed. I'm actually surprised that the smoothing out of the angle weakens the edge on a Euro sword. It makes sense to me, but I'd assumed the amount of material removed was so small that it wouldn't have made a difference.

Would you say that whilst blending out the secondary bevel helps avoid resistance in cutting slightly, the danger of cleaning it up to make it invisible might outweigh that slight benefit? I've read that secondary bevels really don't impede cutting to any great degree, so is the appleseed edge convention purely aesthetic? It seems like there's more to it, or we would probably see a lot more obvious, unashamed secondary bevels on antiques...

Regarding the "most Euro swords" thing - you did indeed say that, but I was focusing on this comment:

Quote:

the most expensive are blended in real well, and the blend may have a name like "appleseed", but its still a different angle right at the cutting edge than the main bevel


I interpreted that as your saying that whilst there is a secondary bevel on most swords, no so-called appleseed edge on any sword actually qualifies as a negation of secondary bevel. But you were talking about the most expensive production swords, as per the first part of the statement - reading it again now it's obvious. Regardless, only a few Euro swords completely lack the secondary bevel, but the trend in the majority is through design wisdom rather than a lack of precision, since too much cleaning up would result in too great a weakening of the edge.
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Jean Thibodeau




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PostPosted: Thu 20 Apr, 2006 5:35 pm    Post subject:         Reply with quote

James;

I don't think smoothing the transition from main bevel to secondary bevel would weaken the edge as what is happening is just putting a curve instead of a ridge line, you are not thinning the blade down by removing the ridge to the degree where you would be back to almost a single bevel again.

Think of the primary bevel as the two sides of a flat ground triangle meeting in a perfectly geometric way: The edge would be very very sharp but also fragile.

Alternatively, think of the two sides of the triangle not meeting each other but a flat square edge a few millimetres wide: If you them grind a flat bevel you get a stronger edge than when the side meet, a more obtuse edge.

Now if you just round out the meeting of the bevels you would have your " appleseed " edge.

The appleseed part being just a rounded instead of flat secondary bevel and not a wide convex bevel very gradual over the entire width of a Katana's primary & blended secondary bevel.

Oh, with tentacular European swords the curve of the lenticular main convex bevel will just transition into the curve of the secondary bevel seamlessly: Somewhat like an accelerating parabolic curve.

Hope this help and does not make things more confusing. You're pretty close but maybe you are almost overthinking it. Big Grin

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James A. Vargscarr




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PostPosted: Thu 20 Apr, 2006 10:27 pm    Post subject:         Reply with quote

I think you're right Jean, I'm definitely overthinking it. I understand the nature of bevelling, but my problem seems to be one of definition.

Jean Thibodeau wrote:

The appleseed part being just a rounded instead of flat secondary bevel and not a wide convex bevel very gradual over the entire width of a Katana's primary & blended secondary bevel.


Rounding the secondary bevel negates its existence, if I understand the definition of the word correctly. From dictionary.com:

Quote:

Bevel: The angle or inclination of a line or surface that meets another at any angle but 90 degrees.


That suggests to me that the secondary bevel formed by two straight lines becomes a single bevel after sufficient rounding creates a single smooth curve.

I know that the edge geometry of European swords is much straighter than the pronounced, continuous curve of a Japanese sword; but since reading Gus's post I'm wondering if the preference for European sword makers to smooth away the secondary bevels on their edges is more of a balancing act between reducing friction and not weakening the edge.
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Angus Trim




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PostPosted: Fri 21 Apr, 2006 6:56 pm    Post subject:         Reply with quote

James A. Vargscarr wrote:
I think you're right Jean, I'm definitely overthinking it. I understand the nature of bevelling, but my problem seems to be one of definition.

Jean Thibodeau wrote:

The appleseed part being just a rounded instead of flat secondary bevel and not a wide convex bevel very gradual over the entire width of a Katana's primary & blended secondary bevel.


Rounding the secondary bevel negates its existence, if I understand the definition of the word correctly. From dictionary.com:

Quote:

Bevel: The angle or inclination of a line or surface that meets another at any angle but 90 degrees.


That suggests to me that the secondary bevel formed by two straight lines becomes a single bevel after sufficient rounding creates a single smooth curve.

I know that the edge geometry of European swords is much straighter than the pronounced, continuous curve of a Japanese sword; but since reading Gus's post I'm wondering if the preference for European sword makers to smooth away the secondary bevels on their edges is more of a balancing act between reducing friction and not weakening the edge.


Hi James

When I am talking secondary bevel and appleseed in the same sentence, what I'm talking about is pretty much what Jean says {he said it better than I}.....But its not really invisible. If you are used to inspecting machined parts, its visible from several feet away, and if you use inspection tools, you can see it real clear.... just laying a straight edge on the main bevel and rolling it to the edge will show you that the "edge bevel" is quite a bit different from the main bevel, even if the main bevel is convex, the convexity will increase at the edge. Ussually you will actually have a flat at the edge too, even if its only 1.5mm or so....... sometimes less......

This is different than a kat's bevel, the convexity of the bevel quite often goes right to the "edge" with very little acceleration.

Sometimes up close, the beveling is quite obvious on antiques. Sometimes its not, sometimes you have to look close and measure close. Then you have some with obvious secondary bevels........ I haven't seen this a lot, but I have seen it...

With the modern swords, the more expensive custom swords by the best smiths quite often the edge bevel is very difficult to make out.

When it comes to cutting performance, its the main bevel angle, the edge bevel angle, and the thickness of the edge before it was sharpened....

Then of course other factors come into play, like the mass behind the cut, the blade geometry, the dynamic balance, rigidity, actual sharpness of the edge, and several other factors...........

swords are fun
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