The "Ask Jo (NinJO) Thread"

Box_Opener

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Jo, since you’re the resident expert (congratulations) I was wondering something: what makes for a good run in a blade sports competition? I know almost nothing about the scoring but what I do know reminds me of tameshigiri. If it’s like tameshigiri then there has to be some cutting form that is more ideal than another. What’s the deal?
 

Jo the Machinist

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Different cuts have different strategies. The most important thing is hitting your target with the correct part of the knife. Your power cuts need to be done closer to the handle where the straws and ropes need to be out at the tip where it is fast. While initially it is helpful to repeat a cut until you figure it out, to really excel, you have to practice moving from cut to cut. Moving from a board (power) to a straw (finesse) is a lot different than just sitting there hitting straws all day. We have 3 tables, so Ben and I are able to work a mini course during our practices.

As for scoring, you get a set amount of points for each successful cut. You add 100 to your points and then subtract your time in seconds. Lowest score wins. If you skip a cut, you not only don't get those points, but they additionally take off that many more, so if you skip a 5 point rope, you not only lose the opportunity for those 5, but you are penalized another 5.
 

Cap’n Smudge

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Different cuts have different strategies. The most important thing is hitting your target with the correct part of the knife. Your power cuts need to be done closer to the handle where the straws and ropes need to be out at the tip where it is fast. While initially it is helpful to repeat a cut until you figure it out, to really excel, you have to practice moving from cut to cut. Moving from a board (power) to a straw (finesse) is a lot different than just sitting there hitting straws all day. We have 3 tables, so Ben and I are able to work a mini course during our practices.

As for scoring, you get a set amount of points for each successful cut. You add 100 to your points and then subtract your time in seconds. Lowest score wins. If you skip a cut, you not only don't get those points, but they additionally take off that many more, so if you skip a 5 point rope, you not only lose the opportunity for those 5, but you are penalized another 5.
Are you saying you weren’t always a badass? That it required practice?
I find that to be a dubious assertion.
 

bluemax_1

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Jo, since you’re the resident expert (congratulations) I was wondering something: what makes for a good run in a blade sports competition? I know almost nothing about the scoring but what I do know reminds me of tameshigiri. If it’s like tameshigiri then there has to be some cutting form that is more ideal than another. What’s the deal?
Another thing that is clear when watching Jo, Ben and Dan competing, is the consistency/accuracy of their technique. Something that no doubt, is the result of a LOT of practice.

It's not just the accuracy of hitting where they're aiming (love watching them precisely nail the first cut with another chop), but knowing how to use their bodies to generate power, controlling the blade contact as Jo mentioned, for power cuts or speed cuts, controlling the edge angles and plane angles, AND being able to do all that at full speed/power.

You mentioned tameshigiri, so I'm guessing you have some experience in that practice. It's not just hitting the mat where you want to, but making contact with the mat with the optimal part of the sword's edge, while maintaining optimal alignment.

There are lots of videos on YT, where someone swings a blade with the alignment rotated a little off, which results in a lot of lateral flexing/deflection of the sword, reducing its penetration and cutting efficiency by a LOT. Blades with spring tempers can survive this, but differentially hardened katana don't do so well with extreme flexion.

I mentioned this before, but I watched a student put a huge bend in an authentic $$$$ shinken, due to an off angle cut. More money than skill/brains, and they didn't bother heeding the instructor's advice to get/use a cheaper practice cutter for tameshigiri.

It's that ability to maintain consistency and accuracy at full speed and power that makes watching Jo and co, so much fun.
 

Box_Opener

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Another thing that is clear when watching Jo, Ben and Dan competing, is the consistency/accuracy of their technique. Something that no doubt, is the result of a LOT of practice.

It's not just the accuracy of hitting where they're aiming (love watching them precisely nail the first cut with another chop), but knowing how to use their bodies to generate power, controlling the blade contact as Jo mentioned, for power cuts or speed cuts, controlling the edge angles and plane angles, AND being able to do all that at full speed/power.

You mentioned tameshigiri, so I'm guessing you have some experience in that practice. It's not just hitting the mat where you want to, but making contact with the mat with the optimal part of the sword's edge, while maintaining optimal alignment.

There are lots of videos on YT, where someone swings a blade with the alignment rotated a little off, which results in a lot of lateral flexing/deflection of the sword, reducing its penetration and cutting efficiency by a LOT. Blades with spring tempers can survive this, but differentially hardened katana don't do so well with extreme flexion.

I mentioned this before, but I watched a student put a huge bend in an authentic $$$$ shinken, due to an off angle cut. More money than skill/brains, and they didn't bother heeding the instructor's advice to get/use a cheaper practice cutter for tameshigiri.

It's that ability to maintain consistency and accuracy at full speed and power that makes watching Jo and co, so much fun.

Interesting, thank you both. I haven't done tameshigiri but I saw a live demo once (I fenced epee during high school and in college, then practiced kendo in Japan and NYC). It's interesting to try to get some sense of the relationship between cutting form and the sport part you're being graded on. Is the course always consistent? Like, is there x distance to the straw and y distance to the rope for example?
 

Nathan the Machinist

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Another thing that is clear when watching Jo, Ben and Dan competing, is the consistency/accuracy of their technique. Something that no doubt, is the result of a LOT of practice.

It's not just the accuracy of hitting where they're aiming (love watching them precisely nail the first cut with another chop), but knowing how to use their bodies to generate power, controlling the blade contact as Jo mentioned, for power cuts or speed cuts, controlling the edge angles and plane angles, AND being able to do all that at full speed/power.

You mentioned tameshigiri, so I'm guessing you have some experience in that practice. It's not just hitting the mat where you want to, but making contact with the mat with the optimal part of the sword's edge, while maintaining optimal alignment.

There are lots of videos on YT, where someone swings a blade with the alignment rotated a little off, which results in a lot of lateral flexing/deflection of the sword, reducing its penetration and cutting efficiency by a LOT. Blades with spring tempers can survive this, but differentially hardened katana don't do so well with extreme flexion.

I mentioned this before, but I watched a student put a huge bend in an authentic $$$$ shinken, due to an off angle cut. More money than skill/brains, and they didn't bother heeding the instructor's advice to get/use a cheaper practice cutter for tameshigiri.

It's that ability to maintain consistency and accuracy at full speed and power that makes watching Jo and co, so much fun.

This is a good post. You're correct, the ability to maintain the rotation of the blade relative to the swing of the blade and then hit that target at the same spot again and again is not an easy skill to master and in fact not even a particularly easy thing to see to the uninformed. people watch these cuts and don't understand what goes into running a course like that in only a minute. I am physically much stronger than Jo and I have lots of cutting experience but I cannot hang with her on these cuts, I have tried many times. This is no joke, you guys don't know what it takes to run one of these courses like Jo and Ben and Dan. I have had the opportunity to try on many occasions, and I am not half bad, but these guys are at another level. It's really pretty cool.
 

h7per

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they were requested ahead of time.
I'm sorry, can I also request ahead of time? if it's possible to pay and pre-order them, no problems with waiting. I see you guys are having some crazy time and schedule.
Much love and respect.

Edit to say, if answer will be negative I will totally understand you, but fingers crossed for positive answer 😁
 
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Jo the Machinist

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I'm sorry, can I also request ahead of time? if it's possible to pay and pre-order them, no problems with waiting. I see you guys are having some crazy time and schedule.
Much love and respect.

Edit to say, if answer will be negative I will totally understand you, but fingers crossed for positive answer 😁
Unfortunately, we are done making scales for these.
 
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