Chinese Crossbows were the most powerful crossbow ever

[Inst]

Storage efficiency does NOT equal to stored energy / draw weight.

Storage efficiency = Stored energy / Input energy. This is not the same, because input energy is loss due to minute structural failure in the bow and heat hysteresis. Let's put it this way; bows have historically been measured in draw weight, and that's a flawed system. The potential of a bow should be measured instead in the level of energy input to push the bow into its designed draw, or alternately, the level of energy a bow can store at its design draw.

As to powerstroke = dynamic efficiency; um, if you've been following the entire Chinese crossbows are superior thread both here and on Historum, the key argument is that the longer powerstroke results in higher dynamic efficiency than short-heavies. Hborgg has been kind enough, with his data on Turkish bows, to show that dynamic efficiency is not a strict function of powerstroke, and if it is, there is somewhat of a loss in efficiency as the powerstroke increases, likely because increased powerstroke results in increased energy, without a compensating increase in the weight of the ammunition.

Regarding posting the same crap over and over again, well, you're more or less recycling content from Historum et al. I could swear that you've posted the crossbow energy comparisons at least twice on this board.

[HackneyedScribe]

I told you to summarize my argument because apparently you don't know what my argument is. So far you failed to summarize my argument, but as one can see the request is justified because you still don't know what my argument is.

Storage efficiency does NOT equal to stored energy / draw weight.

Then give your source to prove it. I already provided mine, if you disagree with it, then prove it instead of listing personal opinion. Please show which source describes the difference between draw weight, how input energy is calculated and show which source states that the storage efficiency = stored energy/input energy. All I see your your personal claims. You accuse me of posting the same thing, but at least I have sources to back up those things, things which you aren't able to provide counterevidence against. Where is your evidence?

I already gave my source that storage efficiency = stored energy/draw weight:

http://www.dryadbows.com/Defining%20...e%20Dryad.pdf: In a way you can think of how much energy a particular bow stores as sort of a "storage efficiency". People who tests lots of bows use a ratio of Stored Energy per Pound of Draw Force, or SE/PDF. This ratio is a handy way of comparing how efficiently one bow design stores energy versus a different design.

http://goldenhordebows.blogspot.com/...cs-of-bow.html Peak Draw Force - i.e., the draw weight of the bow. Knowing this is essential, as it’s the force the archer must maintain at full draw, and can be the limiting factor.

First one shows Storage efficiency = Stored Energy/Peak draw force, second one shows Peak draw force = draw weight. Ergo Storage efficiency = Stored Energy/Draw weight. So as powerstroke(or daw length given the same brace height) increases, so does storage efficiency.



Now where are your sources on this "input energy" and how it differs from draw weight as well as your own definition of "storage efficiency"?

As to powerstroke = dynamic efficiency. um, if you've been following the entire Chinese crossbows are superior thread both here and on Historum, the key argument is that the longer powerstroke results in higher dynamic efficiency than short-heavies. Hborgg has been kind enough, with his data on Turkish bows, to show that dynamic efficiency is not a strict function of powerstroke, and if it is, there is somewhat of a loss in efficiency as the powerstroke increases, likely because increased powerstroke results in increased energy, without a compensating increase in the weight of the ammunition.

For the N-th time, where did I powerstroke = dynamic efficiency? I said repeatedly that I made no such claim, and I implored you to find the specific quotes/post number in which I supposedly claimed such a thing. You failed to provide that, so you are either making a strawman argument on purpose or you have a reading comprehension problem. Before you rant about me "posting the same crap over and over", have you ever thought that it's because YOU post the same strawman argument over and over?

Here is a LIST of places in which I said VERY specifically that powerstroke has no correlation with dynamic efficiency, why are you stuffing words into my mouth?:

Starting from Post 154:

1) So when I speak about greater efficiency powerstroke provides, I am talking about that a long powerstroke crossbow has greater "storage efficiency" because it can achieve more with less draw weight. Storage efficiency is the amount of potential energy (area of the triangle) divided by draw weight (the Y-Axis). That is different from "prod efficiency"(most call dynamic efficiency) that you are going on about. They're not the same thing.

2) For the N-th time, I am talking about "storage efficiency" whereas he confuses it with dynamic efficiency (what I called prod efficiency). The former IS STRONGLY correlated with powerstroke, the other is not. Perhaps if people don't confuse the two DIFFERENT efficiencies as the same thing over and over, then I won't have to post the same material explaining the difference over and over eh? I even bolded it in my last post explaining the difference, so AT LEAST read the bolded part before jumping to conclusions:

You are confused that there are two DIFFERENT types of efficiency I am talking about. You confuse the two as the same thing when they are not. The very fact that the force draw curve shows powerstroke as increasing stored energy is one type of efficiency, sometimes called "storage efficiency". That is the efficiency I mean when speaking about powerstroke, it given two bows of the same draw weight, the one with the higher powerstroke can shoot an arrow faster, all else being equal. Ergo that bow is more efficient for the same draw weight. The other efficiency, the one you are talking about, prod efficiency, is not shown in the force draw curve. As I said, please don't mix the two up. I made it very clear that I am talking about two different types of efficiency, one being the prod efficiency and the other efficiency coming from the powerstroke, ie storage efficiency. Why are you still talking as if I am speaking of only one type?

As long as you do not read/address the relevant material over and over, then I am justified in copying it over and over. If you think what I said is wrong, then please explain why it is wrong, because none of you guys did. Are you saying that storage efficiency and dynamic efficiency are the same? Because a simple google search will show it is not. Are you saying that storage efficiency is not correlated with powerstroke? Because a simple google search will show it is not. Don't complain if I am forced to repeat myself, when you don't even know what you are disagreeing against. I should be the one complaining, having to explain things to people who don't know what they are disagreeing with in the first place. And multiple explanations to those who don't understand only draw accusations of "copying things over and over", when these people should be asking questions instead so they could at least know what I mean before disagreeing with it.

3) In post 154 I made it plenty clear that storage efficiency and stored energy (which I prefer to call potential energy) are different, why do you believe I am confusing the two? I made it VERY clear that:

Stored energy = draw weight * powerstroke /2
Storage efficiency = "stored energy" / "draw weight"
Dynamic efficiency = energy transferred into the projectile/stored energy

If I am confusing the two, please explain which part of the above three equations are wrong. Now, nowhere did I say powerstroke is correlated with dynamic efficiency, where did I say that? Quote it. I said, repeatedly, that Storage effiency is correlated with powerstroke, and that is what I mean when I said powerstroke gave higher efficiency. This should have been common sense on what I meant, but apparently you need quite a bit of explaining. The above equations are what I used to define the set of terms, please tell me in what way the above equations are wrong as it seems to me you are STILL confusing what I mean by storage efficiency. I made it plenty clear that these are the equations I am using, so please explain how I confused "stored energy" with "storage efficiency", when these two equations for "stored energy" and "storage efficiency" are nothing similar. Where did I confuse stored energy with storage efficiency? Prove it. When I talked about storage efficiency, where did I say it as a "description of energy storage"? Quote just where I made such a claim. Show me the quote and post of where I said that, or are you so deadset in disagreeing that you would disagree without even reading what I said? Not cool, man.

http://www.dryadbows.com/Defining%20...e%20Dryad.pdf: In a way you can think of how much energy a particular bow stores as sort of a "storage efficiency". People who tests lots of bows use a ratio of Stored Energy per Pound of Draw Force, or SE/PDF. This ratio is a handy way of comparing how efficiently one bow design stores energy versus a different design.

4)
I already made it very clear that when I speak of the higher efficiency powerstroke brings, I am talking about storage efficiency. You introducing different efficiencies does not make that go away. For example, I said:

The very fact that the force draw curve shows powerstroke as increasing stored energy is one type of efficiency, sometimes called "storage efficiency". That is the efficiency I mean when speaking about powerstroke

^Please explain what part of that sentence makes you believe I am confusing storage efficiency with stored energy.

5) Here you are speaking of dynamic efficiency, which as I already said is not correlated with powerstroke length. Where did I say otherwise, or do you insist on resorting to strawman arguments? I said, repeatedly, that STORAGE EFFICIENCY is affected by powerstroke, I ALSO said repeatedly that dynamic efficiency is NOT affected by powerstroke. Why do you keep talking as if I think dynamic efficiency is correlated by powerstroke? Do you bother reading my post at all? Are you here to read and learn or are you here just to disagree with me no matter what I say?

Now, perhaps you should summarize "the crap I'm pasting over and over" to prove you have a tiny clue of what my argument is, because apparently I haven't pasted them enough. As I said a simple google search can back up what I said, but you are intent on disagreeing not only without doing the google search, but disagreed without having even a clue about what you are disagreeing with.

Now, you keep accusing me of copy/pasting "crap over and over". Please show from post 154 which quote was a copy/paste of my previous posts? Please name the post number of said previous post. And then please tell me how you brought counterevidence to address it, or is saying "this is a copy/paste" enough counter-evidence for you?

6) So in summary, I claimed that powerstroke affects storage efficiency. And what I get in response is a bunch of arguments about how powerstroke does not affect DYNAMIC efficiency. You yourself said "I think, for the information given, Hborgg has shown well how efficiency is not strongly correlated to powerstroke, and it's incumbent on HackneyedScribe to prove, instead of merely reiterating, his thesis," whereas you ignore the fact that Hborgg only showed the effect of powerstroke on DYNAMIC efficiency. Storage efficiency is not the same as dynamic efficiency, apparently trying to explain that multiple times means I am "copying crap over and over". Well maybe I don't have to "copy crap over and over" if you would start reading what you are disagreeing with instead of just disagreeing for the sake of it. When you fail to address old material, then I'm not obligated to bring in new material (even though I did bring new material that you fail to mention).

So long as you talk about efficiency as if there is no difference between storage and dynamic efficiency, then I will reiterate the difference over and over, and I am also more than justified in doing so. Now it seems as if you are trying to hide past mistakes by strawman arguments, claiming that I think storage efficiency as stored energy, even though I already gave equations and explanations showing the difference between the two.

^Each and every one of those examples shows me stating quite clearly that I did NOT say powerstroke results in higher dynamic efficiency, I only said it results in higher STORAGE efficiency. Your style of strawman argument has crossed a line and is unacceptable. If you insist on expanding the discussion to dynamic efficiency, I would say only on extreme cases of very low powerstroke would it have a noticeable effect on dynamic efficiency (why ignore your own example from Bichler), given the same draw weight and lighter quarrels to match the smaller amount of stored energy. Even this it would probably be impossible to see this with bows because bows are not made as light as possible, bowmakers have to consider handshock (crossbowmakers can just put the mass in the stock to deal with the recoil). Hborgg can prove that dynamic efficiency has no correlation with powerstroke all he wants, but that is entirely irrelevant to what my claim about the effect of powerstroke on STORAGE efficiency. Was Hborgg's examples of bows that are the same draw weight? No, it is not. When I give examples of bow performance, it is examples in which all bows tested are tested under an "all else being equal" scenario so we can clearly see the effect of a single variable (ie Bowyer's bible). Was Hborgg's example like that? No it was not. Ergo it suffered from white noise. The impact of powerstroke would not be enough to be noticeable because other variables such as draw weight and stave length would have equivalent or higher impacts that hides it. Much like how height might affect how good one is at basketball, but experience, training and technique would completely eclipse the "height" variable to make it unnoticeable, unless if the height is an extreme case such as Yao Ming. <-I already told this to Hborgg too, but so far nobody addressed it. If you are going to use his example then you should address it instead of ignoring it. In Hborgg's case, variables such as the prod length (which has the biggest correlation relative to its performance, even higher than draw weight, at .769, which is quite high) would likely hide the effect of other variables.

Regarding posting the same crap over and over again, well, you're more or less recycling content from Historum et al.

This isn't historum, so what's your point? Just because some people on historum knows how I got the equation does not mean everyone here does.

I could swear that you've posted the crossbow energy comparisons at least twice on this board.

I posted the crossbow comparison numbers here ONCE, to DESCRIBE how I got the numbers. Am I not allowed to to that? If people don't know how I got a previous equation, am I not allowed to refer back to the previous equation in order to justify how I got the equation? On the other hand, why don't you reflect on your own regurgitated strawman arguments in which you keep talking as if I believe dynamic efficiency is correlated with powerstroke length even though I mentioned multiple times that I did not (Only on this post did I start mentioning that there is an affect during extreme cases). Why not address the counter-arguments I pointed out?

From my arguments with you, it seems as if you feel entitled to not only ignore a counter-argument, but also disallow others from pointing out that same counter-argument to you even when you repeat the same debunked claim over and over. The fact that some previous post is by itself enough to debunk a new claim is ignored. The fact that some previous post should be mentioned because certain people forgot what it said or didn't read what it said is ignored. The fact that some previous post should be brought up for easier access for going through calculations is ignored. With that attitude you're basically justifying yourself in avoiding counterarguments. Ignore some counterargument you don't like and continue repeating your debunked claims. So when people bring up those counterarguments again you can accuse them of "posting the same crap over and over". Where is the effort made to ADDRESS the counterarguments that were ignored? You make it sound as if ignoring the counterargument is somehow a valid rebuttal.

[Sint]

Yeah, just as with the Manchu/Korean bows, not a single surviving example remains and basically everything about it is speculation(and as often with oriental stuff, exaggeration).

Basically the end of the thread.

[HackneyedScribe]

1) there ARE surviving Manchu bows: http://www.manchuarchery.org/content...y-precious-bow
2) what do they have to do with Han crossbows, whose draw weight were passed down to us by contemporary accounting records, alongside accounting records about how many arrow shaft needed fixing or whether the fort wall needed a new coat of paint or the amount of grain a soldier is compensated for or how much a private paid for a cloth of hemp? Such records aren't likely to exaggerate.