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Geoff Keyes

"Unlimited Class" Competition chopper

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I have used various machetes, barongs, khukris in my life and have cut acres of blackberries as well as saplings and just various things that deserved it. I was also heavily into the martial arts in my youth including Kenjutsu/Iado before they were popular.

I have come to the conclusion that there are two equal design principles that are actually opposite sides of the same coin. A Barang, or Parang, with a leaf shaped blade and the khukri, not just a recurve. (Many people use the term "khukri" to describe a recurve blade. Not the same thing)

Given good blade geometry and quality the real difference seems to be completely "in the hands of the beholder". It matters more how the user maximizes the advantages of his/her chosen blade and their own physiology, than it does which style the choose. For instance I found that, as my arm tired, a khukri had the habit of pulling blackberry vines towards me. I didn't like that. OTOH I found the khukri to be more hatchet-like and effective on thicker saplings. If the user is familiar with the "drawing cut" the Barang design can be quite versatile. 

My roundabout way of saying "Horses for courses".

Like so many things it is most important that the tool and the user operate in harmony.

"OHHhhhmmmm":ph34r:

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Cringe-worthy at times, but that's show biz I guess.....

I appreciate it for the sake of the persons that came with skills and proper blades.

I'm watching the 4th episode tonight, and I think by now it's obvious what would work, in it's simplest form a slightly longer competition chopper  would be a good start.

......some great ideas already shown here B)

 

I have a question........the fish.

Skill problem? Stamina/concentration problem? Or just a bloody tough fish? :lol:

I've never chopped at a fish, but I find myself wanting to :ph34r:

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It's mostly a technique problem, but it varies with the competitor. The problem with the fish is that on the belly side, it's pretty "floppy." So when they come in with a horizontal strike on the belly side of the fish, it's just sort of compresses and moves out of the way, so the knife pushes it instead of cutting it. Not only that, since the fish has been gutted, approaching from that side means the competitor is trying to cut into two loose sides, one of which is close to the tip of the knife. All that has to do is slip out and you've already lost.

I think the approach needs to be to cut at a downward angle from the spine. That way you're only biting into a single surface (and it's a supported surface at that, thanks to the spine bones), and the downward angle keeps you from pushing the fish away from the cut. As soon as the knife bites, the downward angle pulls the fish downward, keeping it from swinging and making it more "taut," if you will. The same principles apply for cutting a free hanging rope. If you watch a straight side cut vs. a downward angle cut, you'll see the rope get taut an instant before the complete cut through the rope.

Edited by Mike Andriacco

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This is a fascinating thread! This is the first time I've ever heard of Cloud Cutter--but that thing looks amazing. Somewhere around here I have a blade-like object that looks like a cross between that and the headhunter's sword that Geoff posted. Clearly I need to find it and finish it now. :D
Geoff, thanks for starting this conversation-- lots of food for thought here.

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I have been on a chopper kick lately. I think the top/new blade I am grinding would do well.

Planing on a flat grind with no secondary bevel. According to my  digital torpedo level I am at about 10* a side.

What do you guys think would be too thin as far as a chopper edge. The other blade is about that and it seems to do ok.

When you guys say full flat grind...does that just mean no secondary bevel...or does that mean it runs all the way to the spine of the blade.

I would actually like to try and get on that show. Does anyone know how to go about that??

newchoppas.jpg

Edited by Kreg

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Mike nailed the "fish issue" IMO. I explained it a bit simpler to my wife.

"The spine is the toughest part and it would be best to start the chopping cut there, while you still have the highest blade velocity. Preferrably with a drawing cut so you use more of a cutting technique through the belly."

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As noted earlier, the current season of competitors didnt have the advantage of reviewing previous episodes. So it would be my guess that by the time you get on, the challenges will have changed and may favor something else completely. But I guess that may still make the most well rounded implement the best bet.

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I would make something like this.

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3 hours ago, Kreg said:

I have been on a chopper kick lately. I think the top/new blade I am grinding would do well.

Planing on a flat grind with no secondary bevel. According to my  digital torpedo level I am at about 10* a side.

What do you guys think would be too thin as far as a chopper edge. The other blade is about that and it seems to do ok.

When you guys say full flat grind...does that just mean no secondary bevel...or does that mean it runs all the way to the spine of the blade.

I would actually like to try and get on that show. Does anyone know how to go about that??

newchoppas.jpg

That grind with no secondary bevel is kind of a scandi grind.  Full flat is all the way to the spine.  And try for a 7.5 degree angle, it cuts better.  Finally, dunno about the excessive recurve.  It would be fine for brush, not so hot on a board.

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52 minutes ago, Jeremy Blohm said:

I would make something like this.

I would actually love to see @James Helm do a take on Cloud Cutter. I think his style would pair really really well with the overall shape. Love the neo tibal look. 

@Alan Longmire, do you remember if the handle on Cloud Cutter was a Japanese tang style, stick/hidden tang, or full tang (I guess or just a wrapped bar of steel, but it didn't look like it in the photo)?

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IIRC it's a wrapped full tang, but I don't remember for sure.  The original thread is around here somewhere...

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I've gotten as far as filling out a questionnaire to see if I can go on Season 2.  We'll see.

 

I have two thoughts: 

 

Something like this, with a longer sharpened portion on the spine.  It would balance on the side of power and need a good bit of strength and stamina to wield.

 

36994642873_1fc6edc053.jpgcleaver01 by James Helm, on Flickr

 

And something like this, which would be quicker and lighter:

 

41976820202_af1b08e992_c.jpgbushsword03 by James Helm, on Flickr

Edited by James Helm

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I have no doubt you will get picked. I think both of those would be a great blade to bring. I like the cleaver though.

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11 hours ago, Jeremy Blohm said:

I have no doubt you will get picked. I think both of those would be a great blade to bring. I like the cleaver though.

Oh, there's no telling.  Television is looking for what they think will deliver the most entertainment, not necessarily what will perform the best.  Not to say that I would perform the best, but what they're looking for and what we're looking for do not necessarily align.  :)

 

I'm not going to worry about it.  Got too much to do to get ready for the Blade Show.  :)

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I just gotta say, that show irratates me pretty bad. I want to like it, but the commentators are rediculouse.

"He has da bowie knaf! twaditionly da bowie knafe was used by jim bowie dat he actuawy used to stab in the heart during a duel!!!" 

They just say dumb stuff. 

I like your concepts though! Cloud cutter and James's blade look pretty good for tearing into stuff on the first round, but the second requires more speed and coordination.

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I found the first thread where Cloud Cutter is mentioned, but of course the pics are gone. However:  It is a very good read on the topic of cutting stuff.  Read it and get a dose of the way things used to be around here:

It's on page 518 of Show and Tell.  Talk about a trip back in time...  I highly recommend going back to look at some of the topics and see who was hanging around then.  All the pics are gone, of course, since nobody updated the links after the forum address changed and dfoggknives.com went away.

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Whilst in the shower (where all good thinking gets done) I had a think about blades an' cuttin' an' stuff.  They have allowed double edged blades on the show, so what if one built a blade with 2 edges, a cutting side, for ropes and fish and cutty things, and a chopping side, for ice and sheet metal and other hard materials. 

 

The "cutting" edge, call it E1, would be full length, near zero bevel and razor sharp.  The "chopping" edge, E2, would be half length (tip to about the mid point) and more axe like, more like a very sharp felling axe.  The handle would have to index in a very positive manner, I still think a handle twice as long as I would normally make, to allow an easy 2 hand grip (9-12 inches, depending on taste).  It would take some thought on the users part to decide (under time stress) which edge to use, but it would save the more delicate E1 for important cuts and not beat it up on hard stuff.   I don't know if they are allowed to sharpen between rounds, or if they just have to live with what the course has done to the edge (s).

New drawing time.

 

Geoff

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Geof - That's the idea with my cleaver up above.  :)

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This is for my table at the Blade Show, but is an experiment in how I'm thinking of approaching the challenges on "Knife or Death".  Fully sharpened convex edge on the spine, main cutting edge drops slightly below the level of the knuckles for power, straight handle doesn't favor either edge.  It'll be wrapped in hemp cord over a foundation of neoprene, with three-strand Turk's head knots at the top and bottom of the handle, all impregnated with West System marine epoxy.  Grippy, will accommodate the use of gloves, and will provide a solid mechanical lock to keep it from flying.

 

42223543031_7d28eff097_c.jpgbladeshow7 by James Helm, on Flickr

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There was one guy who had a similar blade that ran the course. He actually dominated. But, during the second round when you have to cut the hanging meat and have it fall straight down to the scales; his blade actually flung the meat too far and it didn't hit the scales. I wonder if this was due to the heft of his blade and perhaps too much of a wedge shaped cross section? Maybe you could put a fuller in the blade to reduce drag on the meat and lighten the blade for recovery? perhaps shaping the blade like a "boat tail" bullet in cross section could allow that jiggling meat to reconform to the shape of the blade as it is slicing in order to drop the meat straight down? 

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I think his problem was more too much swing.  He was putting his whole body into  the swing which sent the meat flying in all directions.  Less of a power cut on that target would have worked better.

Jesse, this is a design I've been working on as well.  Mine is more of a Nagamaki.

Geoff

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14 hours ago, Zeb Camper said:

There was one guy who had a similar blade that ran the course. He actually dominated. But, during the second round when you have to cut the hanging meat and have it fall straight down to the scales; his blade actually flung the meat too far and it didn't hit the scales. I wonder if this was due to the heft of his blade and perhaps too much of a wedge shaped cross section? Maybe you could put a fuller in the blade to reduce drag on the meat and lighten the blade for recovery? perhaps shaping the blade like a "boat tail" bullet in cross section could allow that jiggling meat to reconform to the shape of the blade as it is slicing in order to drop the meat straight down? 

IMO the lenticular (boattail) is the way to go for many reasons.  I do think he used too much "chop" and not enough "slice" in his technique. Needs to read "The Book of Five Rings".:ph34r:.

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