Stacking and string angle

[Fox]

At what length bow for say a 27” draw does stacking and string angle start to be a problem on Flat bows?

[Pat B]

R/D and recurves can pull farther than a straight limb bow before stacking because the string angle.

[Fox]

Right... I should refraze my question, so just talking about flat bows.. would a 56" flat bow drawing 27" be uncomfortable? or how about a 54" I would imagine that would stack pretty bad... would the limit be 58" for it to still be manageable? or 60"??  64"

where would you say the point to where you would need to recurve or make a r/d?

[bradsmith2010]

I think uncomfortable is kind of relative,, I have a 54 inch flat bow that will shoot nice at 27,, but for someone else maybe they dont like it,, I dont mind a little stack at the end of the draw,, i think its more what you used to,, make one and try it,, and see what you think, thats what I did,,,

[Fox]

I do suppose thats true brad.. I can't just get y'all to tell me whats going to be comfortable. darn guess I will have to make one 

[bownarra]

64" for me.
Longer bows have lots of advantages over one too short.
58 - 60" would stack.

[Morgan]

Brad is right, it is what you are used to. I have short and long bows that I like to shoot. My favorite flat bows to shoot all day are always 64-66” but I don’t shy away from the short bows. Longer bows are just smoother to draw  and easier on the fingers for me over a long shooting session.

[Pappy]

I like 60-64 for my 26 inch draw, flipping the tips a bit will help with the stack feeling on shorter bows, most of my shorter bow I just design with a shorter draw length in mind. 27 inch draw for a 54 inch bow is pushing the limits IMO I know others don't think so but for me I double the draw and add the non bending area[handle and fads] for safety/longevity and durability. 
 Pappy

[Zugul]

So it's possibile to make a bow shorter then duble the drow lenght plus stiff handle area and get away without flipping the tips?

[Pat B]

Once the string angle with the limb tip hits 90 degrees the bow stacks. I prefer 60" to 64"-66" for my 26" draw but I built a 47" sinew backed bow with flipped tips that was comfortable for me to shoot at 26".

[Del the cat]

The change in direction of pull around the 90 degree mark doesn't change very quickly.
E.G The component of the force that is trying to stretch the limb rather than pull it back increases once you get past 90... but it only increases slowly at first.
It's a bit like how the length of daylight change noticeably at this time of year (spring/autumn), but you don't notice it much at midsummer or midwinter solstice. (All to do with geometry of a circle)
What I'm really saying is that you have to be noticeably past 90 for it to show up. (Or do we... let's look at the maths)
If you want the arithmetic/geometry I recon it's a reasonable approximation to the cosine of the angle.
So at 90 there is zero force inline with the tip (cos 90 degrees=0)
At 95 (cos 90=0.87) there is 0.087 x the draw weight. so at 50# about 4.5# is pulling along the limb, so I s'pose we'd certainly feel that
At 100 it would be about 8.7# 
Oooh that's quite a lot... maybe my first assertion is wrong 
To me the question is how do we measure the angle?... the string is a nice straight line...but the limb? Do we measure to a line corresponding to the last 3" of limb? Or maybe a line from mid limb to tip? If we took a line from grip to tip, then a flipped tip wouldn't make any difference . Dunno if there is even a proper answer?
Del

[Digital Caveman]

Del, I think you should measure the angle the string makes with the non-bending part of the tips.  These act like levers pulling on a spring.  This would explain why whip tillered bows stack sooner.

[gutpile]

I got a question.. I got a 54" 1 inch wide osage.. I know limits are being pushed now.. I cringe every time I brace it.. lol..tilled out to 25.. 51lbs.. feels like its stacking at 25... could I flip tips to help or am I already too short to do that.. I draw 26 but will more than likely short draw due to this.. its bending boys... LOL... I been considering but I am already out of working limb.. it has a 3 1/2 handle 1" fades..I would try to only flip last 3 inches or so.. I left them stiff anyway..granted.. I would not go hard flip just over the bow maybe 1 1/2 inch .. bow is starting to take a lil set since 23.5 inches.. only about 1/2 inch after un stringing and it seems to settle back overnight..  gut...

[George Tsoukalas]

Reread PatB's post because he gave the essence of what is true.
Yes, reflexing decreases the string angle.
Jawge

[Del the cat]

Del, I think you should measure the angle the string makes with the non-bending part of the tips.  These act like levers pulling on a spring.  This would explain why whip tillered bows stack sooner.

Fair enough
Obviously it's sometimes hard to quantify "non bending, and it's hard to measure and angle to a very short line... but if we say a straight line from the tip to a point 5" in from that, it should pretty much cover it.
Del