Archery FAQ: Stringtwist at Fulldraw and Stringangle of 60 degree 

Interesting idea

Thank you

Maybe try to put less pressure on the arrow with your bow-hand index finger. Worked for me.

Most of the issue with arrows not entering the target straight, and grouping left/right/up/down of intended target, is related to arrows that are not tuned to the bow. Spine too stiff = group right. Spine too soft = group left. Tip too heavy = nock high. Tip too light = nock low. String twist and arrow flight is also related to the natural rotation of the arrow, based on if the fletching is “right wing feathers” or “left wing feathers”, and if helical twist is added into the arrow build. Left wing and right wing rotate the arrow in opposite rotations. For my arrow builds on my Asiatic bow, a left wing feather + a left helical twist produces much better arrow flight, when paired to a well tuned arrow.

Thank you

Thank you for watching

Point thumb at target is something I do also. Helps maintain proper bow arm for me.

Same to you and thanks for watching

+Rudolfo S Jeronimo.... The Segye korean bow from AliBow is very good, and I highly recommend it. I've got 2; one with 50 ib draw and one with 40 ib draw (the reason for this is that from 45 ib and up the drawlength is just 30", from 40 ib and lower the bow can be drawn easy to 32". Know this when you choose)

@@TNTnor maybe the #45@30' could do 31~31.5 inches?

@@rodolfosjeronimo9274 I don't know why there's a gap of 2" draw at around 45 ib, but I felt the difference with my 2 bows. The 50 ib-er was more "stiff" at the end of the draw, and it's almost as it says to you "if you pull me more, I'll snap". I don't thick there's a middle-thing around 45 ib. If you want the heaviest bow to 32", go for the 40 ib-er. It will still kick your arrows (light ones) at least 250 meters, and with a good kick. As Armin's test of the Segye bow tells you, they have a fenomenal drawcurve.

​@@TNTnor I see, thank you for the helpful info!

thank you for watching

Thank you

thank you for watching

Thanks for watching

Thanks

My qing dragon 2 from Mariner has a string angle of 60' at full draw of 36"

Maybe if the draw is too long ( making stringangle over 60°), then fingers of the draw hand will be pinched by the string&shaft because the remaining angle becomes narrower, that's why as a rule of thumb, 60° serves a general reference?

Thank you for watching

Hehe

thanks for watching

Yepp

thank you for watching

thank you

I thank you

have fun

Enjoy

thank you for watching Leith and merry Christmas to you and your family

@@ArminHirmer I appreciate everything Sir. You are an inspiration, I am enjoying my journey of the bow :)

Practice :)

some call it stacking. I would say the bow is beyond optimal performance. stacking for me is, when the bow gets hard to draw

thank you for watching

Hahaha. Thanks for watching

Merry Christmas!!🌲 Brother Archer🎯 enjoy the holidays and keep shooting my Friend Cheers from the Caribbean Island Puerto Rico 🇵🇷🤓🏹👍🏻

@@miguelveratraditionalarche9374 Merry Christmas to you from Croatia.

Thank you. Never read anything about that. Buy even if not, same as with as example the Taichi classics, sometes.they don't explain all :) migth do a speed comparison

Similar question here--is the angle from the string to the tangent of the siyah the correct angle to be talking about in the context of Armin's architecture simile? I understand the application as it relates to architecture and engineering generally, at least when it comes to straight lines, but using the tangent of the siyah where it meets the string-nock interface/corner as the reference point is a bit confusing. My intuition would be to reference the 60deg 'optimal angle' to either the [vertical] chord from string nock to string nock, or maybe to the line intersecting the string-nock vertex and the arrow-pass, or from string-nock vertex to the arrow nocking-point (i.e. the line described by the arrow). I'd love to hear more technical/engineering insight on this point (preferably at a more intuitive level than going straight to the vector equations). Maybe this is down to the interface with the lever of the siyah being the correct reference for this angle, since that might be the moment at which forces peak? Regardless, thanks to Armin--this really made me think about something I'd totally missed.

@@cmcc1442 Mechanical engineer here, with a recently-acquired intense interest in archery. There are two primary design considerations that ultimately affect the ballistic performance of any bow: 1. How much elastic strain energy does the bow store at full draw? 2. How efficiently can that stored energy be transferred to the arrow? Let's tackle the first problem. For maximum energy storage at a given draw weight, the material of the limbs should be stressed as uniformly as possible. The majority of the stress (and therefore stored elastic strain energy) results from the bending moment acting in the limbs. The bending moment acting at any cross section of a limb equals the string force acting on the nock times the perpendicular distance from the nock to the cross section of interest. If the imaginary line segment from a given cross section to the string nock is perpendicular to the string, then the bending moment in that cross section will be maximized, and the strain energy contributed by that cross section will be maximized. It is then easy to see that the optimal geometry of the limbs at full draw is a perfectly straight line from the stiff riser to the string nock, AND, with the string at exactly a 90 degree angle to the entire limb. If the angle is instead 60 degrees, then only sin(60)=86.6% of the string force is actually used to bend the material in the limbs, and cos(60)=50% of the string force goes into axially loading the limbs (note these two percentages do not add to 100% because the force components are in a vector right triangle). However, the geometry of the limbs varies during the entire draw, so the straight alignment should be approached somewhere within the latter half of the draw, with the limb slightly curling away from the archer earlier in the draw and slightly curling toward the archer at the end of the draw, so that the limb is never very far from being perfectly straight at any draw length. Furthermore, the stiff riser should be as long as possible so that the angle of the string varies less, and it can be kept closer to perpendicular to the limb for a greater portion of the draw. Now for the second problem. For maximum efficiency of energy transfer to the arrow, the ratio of arrow speed to limb tip speed should be maximized. If we model the limbs as rigid rods attached to torsion springs at the points where they connect to the stiff riser (a close-enough approximation for our purposes), then it can be shown that for any given angle between the arrow and string, the arrow speed ratio will be maximum when the imaginary line from the stiff riser connection point of the limb to the string nock is at exactly a 90 degree angle to the string. And again, the exact angle will vary throughout the draw, so the geometry should be such that the 90 degree angle is approached somewhere within the latter half of the draw, with an acute angle (ie less than 90 degrees) earlier in the draw, and a slightly obtuse angle (ie greater than 90 degrees) at full draw. So if anything, it is the angle between the string and the straight line segment representing the entire flexing limb (from connection point on the riser to string nock), NOT the angle between the string and siyah tangent, that ultimately matters when evaluating the performance potential of a particular bow design. And funnily enough, if you look at the bow on the tillering tree, you can observe that this angle is actually above 80 degrees at full draw, approaching 90 degrees. The reason it isn't actually past 90 degrees at full draw, as in the optimal case, is because the bow body is too short to fully implement the 90 degree sweep, and stacking would become a problem. However, if the stiff middle-section of the bow were much longer, while keeping the limbs the same length, then the 90 degree sweep could be fully utilized to obtain maximum power out of the bow, without stacking.

:D

Same to you

nachdem Spine nicht so sehr ein Thema ist bei Daumentechnik und da Eindrehen nur ein paar mm ausmacht, bin ich mir nicht sicher. Kann sein

thank you for watching

Yeah well, can happen

@@ArminHirmer probably that broke mine bow from Nika Archery :)

yes I think so, will do more testing and maybe slowmo

I will do another video about it :)

String twist effects instantly, helical fletching during flight

With thumb release the arrow goes on one side, for Mediterranean draw, it goes on the other. Though some people do the opposite, and that's ok too

I shoot with my arrow on the outside, as I use a thumb draw. I started with my arrow resting on the inside, and using a Mediterranean draw, however when I started mounted archery/speed shooting, the outside rest and thumb draw is much more convenient. Plus I have been learning there is more flexibility in what you can add to your technique to improve your shot, such as the string twist shown here, canting the bow, etc.

Frohe Weihnachten :)

Practice

No

What part of Maine are you from I live downeast near Calais nobody around here shoot thumb release do you?

@@tammynfletcher i habe a few ways i practice when i shoot, i shoot Mediterranean, and i also shoot Apache style and i also practice by holding/using my thumb as a release, but ive yet to use a ring, intend on doing this when i build rams horn/birch tree bow ..

@@matthewmaxcy1574 very interested in the birch ram horn bow well if your looking for someone to shoot with if you come this far north look me up

@@tammynfletcher definitely will do...

You have to be careful of course, some bows are more wiggly

Hahaha lustig. Ich würde den Kheshig von Alibow nehmen und einen Asyrer von Grozer :)

Was meinst du mit "und"? Meine Freundin tötet mich wenn ich noch 2 Bögen kaufe 😁 Danke für deine schnelle Antwort und guten Rutsch 😊

Snake recurve by arc Rolan

Snake recurve by arc Rolan

you can use very short arrows and still draw fully. first the arrow will be very light weight and fast, second, the enemy will not be able to shoot them back

@@ArminHirmer that makes sense.

You can see the twist in his early practice at night with curving arrows, and 2x at the last duel. The string is already offset before the release 😊

true, still helical fletching needs a bit until it impacts the arrow. with the twist, you have it directly from start

@@ArminHirmer True. People have experimented with some pretty extreme fletching angles to get the spin started faster. I have even seen fletching that consists of a single feather with a 45 degree spiral.

@@mkultraification of course like flu flu arrows, but they slow down extremely. defeats the purpose in my opinion

Don't expect same efficiency from a longbow than from short bow with long draw. Unlike many belive longbow isn't very good bow at all when it comes to efficiency. They are not long for power, they are long for not to break. Wood alone cannot handle much bending, so to get long draw the bow needs to be long too. Self bows lenght is about 2.2 to 2.5 times the draw lenght, depending of the desing and what wood is used. The shorter bow with same draw lenght is in most cases more efficent cus less dead mass in the limbs and the sting makes it more efficent, because longer bow has more inertia slowing down the arrow, that's why armin always measures the bow lenght and gets this f value. But where the longbow shines is the ease of manufacture. Longbow is quick and cheap to make, so its good option if u need to arm lot of soldiers with little time and money. Low cost mass production is offten better than quality and efficiency in times of war.

depends on your bow. check when the string angle is about 60. usuallynit is around 30" with a good longbow. and still the will never be as efficient as short reflex bows

Thanks very much guys! Merry Christmas you all!