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Bows / Re: Black locusts bow
« Last post by Selfbowman on Today at 07:52:43 pm »Day five 32.1 will check it for three more days to see if it changes.
Recent Posts
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Primitive Skills / Re: A simple leather project
« Last post by Pappy on Today at 07:23:17 pm »Nice BJ , looks like you are pretty good with leather to me. Pappy
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Bows / Re: The best shape for a reflexed bow?
« Last post by Badger on Today at 07:14:54 pm » Are you saying shorter bows store more energy? I believe this to be false I have never seen anything to support this.
Shorter bows automatically store more energy - this we know - and also that reflex is another key factor. Now we have same length and same reflex. So the small differences we see come from the sideprofile (and tiller)
I would agree that short bows tend to be more efficient. Many here will agree that right about 67" is an optimum length. .
Shorter bows automatically store more energy - this we know - and also that reflex is another key factor. Now we have same length and same reflex. So the small differences we see come from the sideprofile (and tiller)
I would agree that short bows tend to be more efficient. Many here will agree that right about 67" is an optimum length. .
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Bows / Re: The best shape for a reflexed bow?
« Last post by sleek on Today at 06:16:26 pm »yes, Tuomo, I had around 50 or so different bows from different bowmakers on the shooting machine....maybe post that in a seperate thread, its sure interesting.
How do you optimize the front profile
The longbow is self stabilizing when strung - you can make it as narrow as you like without getting into stability issiues. A recurve needs a certain width at its base. At the same spot the longbow can be made much narrower resulting in a different top profile and mass difference. Your experiment does not take in acount relevant specific characeristics of the design. Namely the lighter limbs of a longbow, and the extra mass of recurves. If we compare the experiment with reality we also must say, that you put recurves mainly on shorter bows - 68" is a bit long to make a recurve.
But this is all about fps. If we only talk about stored energy and sideprofile and leave the fps aside, this a very good experiment.
Shorter bows automatically store more energy - this we know - and also that reflex is another key factor. Now we have same length and same reflex. So the small differences we see come from the sideprofile (and tiller).
Maybe Tuomo could upload the force-draw-curves? Visualizing the stored energy? Maybe we see a nice hump in the curve of the d/r?
And Tuomo: Do these bows all have same length of string? Any Differences?
Gettin' curious again
Do you still have the shooting machine set up? Im very interested in your experiments, please do post it, here or on another thread.
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Bows / Re: The best shape for a reflexed bow?
« Last post by simk on Today at 05:33:45 pm »yes, Tuomo, I had around 50 or so different bows from different bowmakers on the shooting machine....maybe post that in a seperate thread, its sure interesting.
How do you optimize the front profile
The longbow is self stabilizing when strung - you can make it as narrow as you like without getting into stability issiues. A recurve needs a certain width at its base. At the same spot the longbow can be made much narrower resulting in a different top profile and mass difference. Your experiment does not take in acount relevant specific characeristics of the design. Namely the lighter limbs of a longbow, and the extra mass of recurves. If we compare the experiment with reality we also must say, that you put recurves mainly on shorter bows - 68" is a bit long to make a recurve.
But this is all about fps. If we only talk about stored energy and sideprofile and leave the fps aside, this a very good experiment.
Shorter bows automatically store more energy - this we know - and also that reflex is another key factor. Now we have same length and same reflex. So the small differences we see come from the sideprofile (and tiller).
Maybe Tuomo could upload the force-draw-curves? Visualizing the stored energy? Maybe we see a nice hump in the curve of the d/r?
And Tuomo: Do these bows all have same length of string? Any Differences?
Gettin' curious again
How do you optimize the front profile
The longbow is self stabilizing when strung - you can make it as narrow as you like without getting into stability issiues. A recurve needs a certain width at its base. At the same spot the longbow can be made much narrower resulting in a different top profile and mass difference. Your experiment does not take in acount relevant specific characeristics of the design. Namely the lighter limbs of a longbow, and the extra mass of recurves. If we compare the experiment with reality we also must say, that you put recurves mainly on shorter bows - 68" is a bit long to make a recurve.
But this is all about fps. If we only talk about stored energy and sideprofile and leave the fps aside, this a very good experiment.
Shorter bows automatically store more energy - this we know - and also that reflex is another key factor. Now we have same length and same reflex. So the small differences we see come from the sideprofile (and tiller).
Maybe Tuomo could upload the force-draw-curves? Visualizing the stored energy? Maybe we see a nice hump in the curve of the d/r?
And Tuomo: Do these bows all have same length of string? Any Differences?
Gettin' curious again
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Bows / Re: Snake bow
« Last post by bjrogg on Today at 05:00:39 pm »Gotta agree with Badger.
Looking good Arvin
Bjrogg
Looking good Arvin
Bjrogg
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Bows / Re: The best shape for a reflexed bow?
« Last post by Tuomo on Today at 04:05:13 pm »Nice idea, Willie, and definitely worth trying. But I see many problems as well. How can I be sure that strain distribution is the main feature of an exceptional bow? Why not mass or curvature distribution, or the side profile combined with some other parameter?
I don’t have an exceptional bow—just some good ones. Their common features are that they have minimal set and they are deflex-reflexed. Set is a material-related parameter, and when making wooden bows, minimizing set is only possible when strain is distributed as evenly as possible. I’m going to make some bamboo-horn bows in the near future, so with horn the set parameter is almost eliminated. Simk has made a lot of very fast horn-belly bows and has taken very good and reliable measurements of their performance (see Traditionell Bogenschiessen 117), so there is potential. But again, this is how we implement theory in a real-life bow.
So, I’m going to make deflex-reflex (or even deflex-reflex-recurve) bows with evenly distributed strain and test them. A long to-do list…
I don’t have an exceptional bow—just some good ones. Their common features are that they have minimal set and they are deflex-reflexed. Set is a material-related parameter, and when making wooden bows, minimizing set is only possible when strain is distributed as evenly as possible. I’m going to make some bamboo-horn bows in the near future, so with horn the set parameter is almost eliminated. Simk has made a lot of very fast horn-belly bows and has taken very good and reliable measurements of their performance (see Traditionell Bogenschiessen 117), so there is potential. But again, this is how we implement theory in a real-life bow.
So, I’m going to make deflex-reflex (or even deflex-reflex-recurve) bows with evenly distributed strain and test them. A long to-do list…
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Around the Campfire / Shipping option
« Last post by JW_Halverson on Today at 04:01:30 pm »Caleb Flies recommended to me using a company called Pirate Ship to send bows to folks. I used to be shipping a bow for twenty bucks, but have been paying as high as seventy-five lately! I was skeptical, but went to the website, registered, and created my first shipping label. You gotta be able to weigh the package accurately, AND enter the dimensions, but it's really not that hard to do.
Pirate Ship has you pay them the shipping (and in this case, insurance charges), then you print out a USPS shipping label that has all the pertinent info on it including their QR codes and bar codes. Easy peasy. What did it cost me? $23 and change, that's it.
How come this works, doesn't the Post Office have set rates for postage? Yes, they do. One set for people walking into the post office and another for businesses that negotiate lower rates for large bulk shipping. Catalog companies, online sellers, and the big sellers all get insane discounts that WE THE PEOPLE are excluded from getting. Companies like Pirate Ship open the back door to us so that we can piggy-back on their contracts. I am sure there are other start-ups doing the same, maybe some better, but I'm already impressed with this outfit.
A bunch of other folks have been telling me they have had excellent luck with Pirate Ship, so I went into this with a little confidence. Maybe you all have known about this forever, but maybe this will help others. As the great Canadian philosopher Red Green said, "We're all in this together." And keep yer stick on the ice.
Pirate Ship has you pay them the shipping (and in this case, insurance charges), then you print out a USPS shipping label that has all the pertinent info on it including their QR codes and bar codes. Easy peasy. What did it cost me? $23 and change, that's it.
How come this works, doesn't the Post Office have set rates for postage? Yes, they do. One set for people walking into the post office and another for businesses that negotiate lower rates for large bulk shipping. Catalog companies, online sellers, and the big sellers all get insane discounts that WE THE PEOPLE are excluded from getting. Companies like Pirate Ship open the back door to us so that we can piggy-back on their contracts. I am sure there are other start-ups doing the same, maybe some better, but I'm already impressed with this outfit.
A bunch of other folks have been telling me they have had excellent luck with Pirate Ship, so I went into this with a little confidence. Maybe you all have known about this forever, but maybe this will help others. As the great Canadian philosopher Red Green said, "We're all in this together." And keep yer stick on the ice.