Reflex-Deflex Design Question

[dragonman]

I have experimented with these designs and agree, I cant see the purpose of putting in deflex in terms of efficiency....it does to appear to make a bow slightly more stable though and the limbs less inclined to twist, as they are prone to do with narrow highly reflexed bows..

I think if a bow is too reflexed it is prone to take a set and end up with a deflex because of set...these bows look attractive because of the curves, then people just copied this, thinking it was part of the design....just my ideas.... though from my own experience   2 otherwise equal bows, one with just reflex and the other with a reflex and deflex...the one with only reflex is the fastest

[Emmet]

I have an rd bow I made last year to stray strung and shoot many shots. It has more deflex then reflex so the tip are 1.5" behind the the handle at rest. I also have a shorter draw at 26" The limbs are heavy enough to get 50# at 26" Its not my fastest bow for sure but not bad either. Its accurate more then others Ive made and no noticeable string follow after shooting all day. I score higher at 3d shoots with it then  recurves Ive tried.

[Del the cat]

How I look at it...
Basically, you can only get so much out of the wood. You can have a fair bit of reflex and a short draw like in a flight bow, but if you want long draw as well the wood simply can't handle it. The deflex allows you to maintain the advantageous string andge and inproved endergy storage of the reflex whilst allowing a bit more draw adding stability and removing some of the stress that the just reflex design would have.
Yeah you can make a heavilly reflexed design, pull a long draw and cause a load of set spoiling the performance... if you design the "set" already in there as deflex... you get your performance and draw length without ruining the wood.
Ok not very technical, but it is my gut feel approach to trying to understand it... better than a shed load of maths and physics which is only an aproximation anyway .
Del

[willie]

Some good replies here being posted. It might be useful to know,  how much more performance is commonly realized with this design. I have read many claims for the theory, but have also built a few bows that were not so fast,  after a while.....

[Traxx]

My Take on this design.
I think most today,that put performance numbers as a first criteria,have a hard time,understanding the benefits of this design,that would have been beneficial to those that utilized it under the conditions that they required.

While they were used from the ground as well,it was primarily designed for a mounted archery bow.The ease of brace would be a bonus in a n impromptu situation.The early softer draw would also be easier to manage,from the back of a running horse,over uneven terrain and still maintain a proper grip,shaft control and ease of partial draw,at the ready for a quick snap shot,when it presented itself.With the augmented pinch style that many used to grip the string and nock and the draw style used with this style of bow,it resulted in softer early draw that gained as it was drawn and often resulted in stack,toward the rear of the draw,with the result being the release being ripped from the fingers at a pre designed draw length.Think about the benefit of  easy partial draw and only having to hold high draw weight,for a small percentage of the late draw,in a fast moving,high stress quick action  shot with a small window of opportunity a hunting and mounted warfare situation,would often present.If there wast benefit to the design,i wouldnt think that so many people from such a broad range of territory,would have utilized it to feed and protect their people,when other designs could have just as easily been made.

[willie]

If I understand you correctly, Traxx, the low early draw weight (that comes with deflex) is the primary feature, and the reflex is added to bring the weight up to a usable range within a short draw?

We often forget that form follows function in this day and age.

[Traxx]

Exactly Willie.....
I much prefer your shorter winded version to mine and may adapt your version,in future discussions of the subject.
with your permission of course.

[willie]

of course you can adapt it any way you wish, Traxx.

I have often suspected that many of the designs we appreciate from the past, were designed the way they were, for practical reasons not realized now a days.

I was intrigued by this description of the shooting style... possibly even utilizing stacking by design?

with the result being the release being ripped from the fingers at a pre designed draw length

perhaps a subject for another thread, or has it been discussed before?

[PatM]

Switching the topic to gull wing bows might be throwing some people off the original topic a bit.

[Badger]

  One problem I see with bows that reflex out of the handle is that they don't come around right when drawing and will tend to stack. A bow deflexed out of the handle will come around much smoother. A horn bow can get away with it because of its long static area and large hooks. A wood bow needs more working limb and cannot be designed like a horn bow and expected to act the same way.

[Traxx]

Switching the topic to gull wing bows might be throwing some people off the original topic a bit.

Based on the description of the original post,i thought gull wing bows,were what he was trying  to convey,or was i mistaken?

[DC]

Switching the topic to gull wing bows might be throwing some people off the original topic a bit.

Based on the description of the original post,i thought gull wing bows,were what he was trying  to convey,or was i mistaken?

That's what I thought until Pat pointed out that the red line is not a string.

[Traxx]

I think,that in the first 2 examples,that it was to show the correlation of tip to handle,but in the 3rd example,i thought it to show the braced example.

What say you gfugal

[Traxx]

If i am mistaken,then i just wasted peoples time and some of my own,with senseless typing.

[DC]

I think all three were to show the correlation of tip to handle but I'm willing to be wrong