Archery Talk Forum banner
41 - 59 of 59 Posts
So, can you englishfy this?

Sounds interesting, but I'm not grasping the lingo.
ok, preload, is how far the limbs travel from unstrung to strung,

so with this understanding.
the reflex in the limb (forward pointing) casues the limb to flip flop back and forth. (take any reflex/deflex limb design, and drop the BH to 3" and it will flip top to bottom in a horrible way)
so with heavy limb pad angles. (pointing the limbs at the archer) that you see on recurves. such as the Bear riser. the longbow limb points soooo far back. that you need a high brace height to give enough preload to open up the reflex. (straighten the limb out)
so if you point the limb forward at the limb pocket, you can preload the limb more, but still have a lower Brace height.

So the limb straightens up.

if you look at all hybrid/R/D bows, the limbs come dam near straight out the riser.
if you look at recurves, the limbs are slopped back to the archer.
These two aspects don't mix.

Kegan (I think) has been struggling to get a lower BH, to become stable due to poor preload of the slack angles. giving a floppy bow.
If he increases the BH, he chokes off the energy in the bow. giving poor performance.

kick the limbs forward more, and you get a solution that works better.

You cant do that with the limb angle due to the need to run a recurve limb, so our solution was to thicken up the limb butt rocker. as per the pictures.
This still gives a Longbow limb but its more forward pointing. and this means that the lower BH still has the preload, without killing the limb shape.

a bow needs to look right, it needs to perform well, and it needs a simple solution to the problem.

That's the most simple we could come up with.
 
i dare say give a bow too much preload and it goes noodly too.
im sure most of us have had a bow at some point where you rest the bottom limb tip on your foot and the riser sags. droops down top pocket inwards bottom pocket outward.
this gives a vertical instability that you dont want either.
really light weight target setups do this.
 
Sid, what would happen if you reduced the working limb to the center 10" of a limb, where the ends were stiff and the center was stiff, and then loaded up the reflex to thin the limb so they could be flexible enough to handle the bend? If it's a longbow, you could needle the now extra-stiff tips to reduce mass, but would all that reflex still have the substantial vertical instability issues that are such a part of extra-reflexed bows?
 
Sid, what would happen if you reduced the working limb to the center 10" of a limb, where the ends were stiff and the center was stiff, and then loaded up the reflex to thin the limb so they could be flexible enough to handle the bend? If it's a longbow, you could needle the now extra-stiff tips to reduce mass, but would all that reflex still have the substantial vertical instability issues that are such a part of extra-reflexed bows?
it would be nasty to tiller. from your perspective.
if you have ever made a longbow overly slim. it starts to wander all over the place
but the second issue we found is that even thou the limb follows the string therefor is naturally by design more stable.
the act of paradox means that the skinny limb will still want to wander.
esp if its wanting to show its reflexed former profile.
id say its a rod for your own back trying to tiller it.
but.... you might have a different solution to solve those hickups.
 
I figured it would be a tough tiller. I have a couple ideas on what I'd like to try, I'm just hesitant about the vertical instability (which has become the bane of my existence:lol:).

I really appreciate the advice!
 
too much limb preload. and not enough limb pad preload if the makes sense.

at least that was what we found with ours.

you limb being too reflexed means when you cut it down it looses the reflex and becomes more stable.
but it you make the limb pads more agressive it works the limb more.

if you can. shim the limbs forward to simulate a more agggressive pad angle and watch the stable brace hieght drop.
 
Will do! I have a limb form that's right on the edge as far as limb load, but I'll definately try altering my wedge. Sure beats having to start over from scratch on a new form:lol:
 
i didnt mean make a new limb. if your bolt system allows. stick a credit card or two under the leading edge.
your just testing a theory so anything goes.
so if it were ilf. then put something under the rocker and crank in the tiller bolt to make it aggressive.
 
Joe, the vertical stability thing is a real pain in the behind, and you can dig your self into a deep hole with it.

I read that Kegan was trying to make a takedown possability of a recurve, so it kinda mad 2 + 2 in my head that its those pesky recurve limb pad angles with longbow limbs.
as i say, ILF is no standard, all its got to do is fit 95% of the risers out there, and while 99" of them dont have a top cover to the pocket then you can change the depth of the limb butt to help fix the problem.
We dam near doubled the thickness of the rocker. to get our limbs to run at about 1-1.5" lower than the other limbs on the market with this trick. this solves the exact problem Kegan is facing. ( i think)

Its about looking at the problem, Looking at the options available and fixing it as best you can.
 
I always want to make new limbs! Actually I don't have a set that I can shim. Wrecked the last set by taking it too far on tapering.

That's the exact issue I'm having though, tons of limb pad deflex and LB limbs just noodling like crazy!
 
Another good shim material is the metal sheet sold at most hardware stores. They have it in different metals and thickness.
Light Lighting Ceiling Table Architecture

It can easily be cut with tin snips/metal shears (that is why the pictured material shows deformation), jig saw or band saw.
I used to use layers of beer cans and/or mylar sheet (purchased at art supply stores) to shim my skeg(s) in my boards.
Makes for a good temporary fix.
 
For some one piece hybrids (Harrier Royal and Triple Crown for example) it appears that the deflex off the riser though the fades towards "1/4" limb is more extreme than MOST longbows? Also the reflex out on the limb is "centered" more towards the tips (past 50% or mid limb?) thus getting the D shape with out reflex when strung.
 
41 - 59 of 59 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top