Limb Stability

[Turkeys Fear Me]

Originally posted by Keep It Simple Archery:
I disagree with that last statement. My reason for this is a recurve is generally more ribbon like. The reason for this is the recurve generally has a wider limb and less core and as a result will is easier to flex in either direction.

Again, I would agree with you, but only to the extent that the thinner core, wider limb is straight(er).  The curve itself resists twisting, allowing a thinner, yet shallower core to work.  In my opinion, that's why the ILF longbow limbs can have issues in that area.  They've eliminated the curve, which is what was helping with the torsional stability.

[Turkeys Fear Me]

Originally posted by Kirkll:


The ultimate recurve bow would have a deep core, and narrow width that has both torsional and vertical stability.....But.... that one is a tough one to pull off..... we have some nice hybrid long bows out there doing it......but.... we are getting closer all the time finding the ultimate recurve bow....

Now we're getting down to business.  THAT, in my opinion is what Border is trying to accomplish. By making the curve larger and tighter, he can narrow out the last few inches of the limb  profile and still keep the core thin.  BUT, by doing so, in other people's opinion, you create other not so friendly issues.

They key is finding the happy medium.

[Bill Carlsen]

The best thing about Border is that they think outside the box and push all the limits and make other bowyers try harder. The bad thing is that they are in Scotland. I surely hope that Bob M can accomplish what he is trying to do.

Turkeys...just curious....i'm not a bowyer but what "other not so friendly issues" are you referring to with Border limbs. I'm soon to be 68 and have shot some of the best and a lot of the not so good bows over the years. Winex and Borders, aside from the Groves, have been the best shooters for me. The biggest problem with HEX series of Border limbs is stringing them but even that is not an issue if you use the stringer they send you.

[Turkeys Fear Me]

Originally posted by Bill Carlsen:
Turkeys...just curious....i'm not a bowyer but what "other not so friendly issues" are you referring to with Border limbs.  

Bill...

I have no personal experience with the Borders other than shooting them a few times.  The people that I know that own them love them but as you said, they are a little temperamental when it comes to stringing them, and some have even said keeping them strung.

This is just a personal opinion, but I would question the ability of such a tight curve to withstand expansion and compression forces long term. It may NEVER be a problem but I wonder if that might be why Border seems to be so sensitive when it comes to what limbs are used on what risers and with what arrow weights.

You are right, they do think outside the box and make people re-think their positions.

[**DONOTDELETE**]

Originally posted by Turkeys Fear Me:
 

Originally posted by Kirkll:


The ultimate recurve bow would have a deep core, and narrow width that has both torsional and vertical stability.....But.... that one is a tough one to pull off..... we have some nice hybrid long bows out there doing it......but.... we are getting closer all the time finding the ultimate recurve bow....

Now we're getting down to business.  THAT, in my opinion is what Border is trying to accomplish. By making the curve larger and tighter, he can narrow out the last few inches of the limb  profile and still keep the core thin.  BUT, by doing so, in other people's opinion, you create other not so friendly issues.

They key is finding the happy medium. [/b]

Well that's not entirely the case regarding the tighter radius hook and the ability to narrow the tips. i can build a totally static tip just using glass and tip wedges and can accomplish very narrow tips....  

Actually What boarder has going for them is that they lay up their own carbon matrix material and have developed a core material that is compatible.
 
A radical hook on the end of any recurve limb puts a tremendous amount of pressure on the working limb. The carbon composites, if used correctly allows you to narrow up the whole limb and push the envelope on the geometry. The geometry part of it is had  explain, and all the stored energy in the world isn't going to do you any good if you can't harvest it..... getting the right amount of preload to stop those hooks dead, transfer the energy, and stay within reasonable stacking limits is the key.

Hey Bill, i know you are a big Boarder fan, and i'm not saying they they don't make an excellent bow, because they do.... But Boarder has nothing to do with how hard i try, or set my prototype goals. or any other bowyer i know either for that matter.

This thread isn't about this brand is better than that brand. it's about stability. and i certainly don't see Sid in here contributing to to this topic.

Those boys over there have had their share of set backs too...Carbon alone doesn't make the bow.

[Turkeys Fear Me]

Originally posted by Kirkll:
Well that's not entirely the case regarding the tighter radius hook and the ability to narrow the tips. i can build a totally static tip just using glass and tip wedges and can accomplish very narrow tips....  

But what good is it?  By doing that, you lose all the benefits of a working recurve and you've accomplished nothing other than narrow, heavy tips that will likely compromise yor dental work.  It's the deep hook and the narrow tips combined that give the performance gains.

But, you are still trading them for what some consider less desireable traits, especially in a hunting limb.

[**DONOTDELETE**]

What i was referring to is pretty much a static tip hook, not so much a working recurve. The advantages of a static tip is a shorter working limb without loss of the string angle. the static tips are generally harder to keep stable the farther out on the hook you go. the heavier tips on a recurve won't effect vibration near as much as lack of pre-load and improper timing. It's all a balancing act i find fascinating myself.

you can even incorporate a static tip into a r/d long bow to help pic up some early weight and help the shorter draw length shooters pick up more performance. flipping the tip a bit on a long bow makes a huge difference in getting better string tension at a lower brace and improves the string angle too.

[Turkeys Fear Me]

It's a shame we don't have one independent testing facility where all these theories can be stacked up against each other.  Kind of like the Consumers Report of traditional bows.

Until then we will just have dozens of different designs, all purported to be the best, many times for reasons that can't really be measured.

[Bill Carlsen]

I'm not technically knowledgeable enough to even get into this discussion but I have to say that when I got my first set of ILF limbs and DAS riser for my wife I shot one arrow with it when setting it up for her and went in and ordered one for myself. At that time there was a lot of sentiment about the bow being "non trad" and my only response to the whole issue was that the bar on limb performance had been raised. I am actually happy to see this discussion as I think it is long overdue. There is a lot to be said for the beauty and allure of all wood bows, but with new limb materials, designs and lots of other new ideas I look forward to bow performance getting more attention than the cosmetics. The prettiest thing to me is seeing that arrow going where it was intended to go, quickly, smoothly and consistently.  I truly think the best is yet to come regarding bow performance. You guys keep playing with your ideas. It is time the Asians got some competition.

[Sixby]

Here is the problem I have with the way this conversation is going. I was building this limb you are talking about , Deep hook. static. Stable laterally and verticly before Border ever came out with theirs Hex 5 and Hex 6.
Kirk was building a static tip carbon bow that is stable and super fast. Both bows utilize 1 1/2 inch width limbs,.
The only thing Border has that I have not worked with is the composit core. I guess. I have not personally seen it.

 Border was touting maple limb cores when I know Bob Morrison , Hummingbird , Kirk and I were building foam core double carbon bows.

Its the following Borders example remark that kind of got under my skin. I apologize for that.

Mr Carlsen I understand you have never shot one of my bows. Have you ever shot a Bigfoot or a foam core Hummingbird or foam core carbon Morrison?

Bob testing stability and using new materials is not something new. It is something we all do if we want to produce a better product. He is not one of the bowyers that is behind the eightball. But there certainly are some.

God bless you, Steve

[Sixby]

Turkeys Fear:But what good is it? By doing that, you lose all the benefits of a working recurve and you've accomplished nothing other than narrow, heavy tips that will likely compromise yor dental work. It's the deep hook and the narrow tips combined that give the performance gains.

Did you read Kirks post you posted and answered. He said he could build a static tip using only the glass and wood with a tight radius. It adds no tip weight at all. A tiny tip wedge that you way more than make up for with narrowing the tip material.
You say there is no benefit. Then you simply need to shoot one.
What you said about compromising your dental work is absolutely wrong. The static bows that I build and that Kirk builds are some of the smoothest shooting most shock free bows in the world. Kirk can show you a vidio if you want that shows limb movement after the shot. Vibration and ossilation, His bow limb stops a tremendously long time before any other bow limb tested. In fact its amazing.
I own one of his bows and that is why I keep using them as an example. I know that the limb works.
You make broad statements like this and expect respect.
For instance. You say the static tip as described have less desireable traits than a working recurve.
I disagree and I can give you reasons for my disagreement. Can you back up the broad statement you made with fact? What are these less desireable traits ? Why is the static tip inferior? Oh and what in the world has this got to do with Bob's thread on Stability?

God bless you, /Steve

[Turkeys Fear Me]

Originally posted by Sixby:
Did you read Kirks post you posted and answered. He said he could build a static tip using only the glass and wood with a tight radius. It adds no tip weight at all. A tiny tip wedge that you way more than make up for with narrowing the tip material.
You say there is no benefit. Then you simply need to shoot one.
What you said about compromising your dental work is absolutely wrong. The static bows that I build and that Kirk builds are some of the smoothest shooting most shock free bows in the world.  

Yes, I read his post very closely.  The only way I can answer your question is to simply say that we seem to have differing definitions of what a static recurve is.  

The tip of a true static recurve does not uncurl...at all.  A true "static" tip, by definition, exerts force by reason of weight alone without motion.  I was referring to the static tips of old, not a radical hook, which seems to be what is now considered by some to be a static tip.

It's easy for someone to say that they make some of the smoothest, shock free limbs in the world. Without independent, objective testing, nobody can prove you wrong.

Or right.

[FerretWYO]

This thread was started to get a few ideas. Look where a few of you have taken it.  Done.