wavy handle Brace height question

[Postman]

The lower limb on this osage "starts out" about 3/8 of an  inch behind the upper limb due to natural curviness in the handle area. All else being equal, Should this be accounted for with a slightly asymmetrical brace height (lower on bottom) between the limbs? Index finger is on arrow pass in the photo....

This bow has been a real challenge - lotsa quirks in the wood, very stubborn responding to the heat gun.  Hopefully I can get 'er shootin' and post soon.

Thanks-
John

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[adb]

I'm not 100% sure that I'm following you, but if I am: uneven brace height = uneven tiller... period. Of course we're not talking about small +/- tillering of the limbs to compensate for unequal length, as this is something done intentionally from the beginning. Make the "natural curviness" even... one of the great challenges of character stave bows.

[radius]

be interesting to see how you work it, John...can you post a pic of the bow at low brace so we can see?

[Dauntless]

Both limbs need to bend evenly.  With that in mind, the brace and full draw on that bow will have the lower limb looking stiffer.  I won't be because it will have bent just as much as the other limb.  If you try and achieve a symmetrical tiller, the bottom limb will work too hard and might break or take excessive set.

I does complicate things a bit though.

[Pat B]

With wood bows the only time to measure tiller is at full draw. What a bow looks like at brace doesn't necessarily matter. When tuning your arrows you will find a sweet spot as the brace height but that is determined by arrow flight and not the evenness or unevenness of the handle or brace height.

[Postman]

Thanks - I'll try to concentrate on the final tiller instead of brace.

[adb]

With wood bows the only time to measure tiller is at full draw. What a bow looks like at brace doesn't necessarily matter. When tuning your arrows you will find a sweet spot as the brace height but that is determined by arrow flight and not the evenness or unevenness of the handle or brace height.

I couldn't disagree more! I think ignoring your brace profile at any time during tillering is a mistake. Any problem at brace, will be magnified at full draw. Your early brace profile is a good indication that you're on the right track. Uneven tiller at brace will not magically change into even tiller at draw.

I do agree with determining brace height... you have to fiddle with it to find the sweet spot. Too low = excessive noise and wrist slap. Too high is hard on the bow, and increases set.

[Postman]

OK - I don't know why I'm so obsessed with the shorter lower limb - I seem to get it stronger, get a decent brace going, exercise the heck out of what seems to be a good, positive tiller, then lose it during shoot in as it gets weaker. Might y'all consider heat gunning to tweak this one's lower limb a bit stronger? It's 48# at 27". She's not done, so no BOM yet, please.... gotta redo my wrap on a  lower limb crack and finish the handle area. probably should have used the top limb as thew bottom, but during layout it's flaws seemed worse.  A knot i was scared of  near the middle of the limb turned out to be quite strong, and is actually still a little flat. Top limb is on the left with the knots in the top of the fade, lower on right has the "whoop-de-do"....if that's the correct term

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[Dauntless]

That looks perfect.  You can call them Whoop-de-does, I call them headaches. 

[Pappy]

Looks pretty good to me,a lot of time when you are working with knots and dips and dives in
a bow you just have to take what it gives.You have to remember you ant working with glass.
I also have to agree with adb on the brace,at least for me I try and keep it correct as I am tillering,if it gets off much usually the full draw is off also.I keep close tabs on it as I go along.
    Pappy

[GregB]

I think there are times when you won't, or shouldn't have the brace to a even "measured" (top limb approximately 1/4" weaker then bottom if bow is laid out with same length limbs) distance. The triplet bow I'm currently working on is very snakey, and the limbs are coming out of the handle area at big time different angles due to wavy grain in the handle/fades. I tried to straighten it out some and ended up with a crack in the fade due to excessive stress applied. If you're not careful and you're trying to get the limbs even at brace measuring perpendicular off the string to the belly, you could end up with one limb a lot weaker then the other just due to trying to compensate for the different angles the limbs are physically at coming out of the handle.

For more even bows which 9 times out of 10 are the case, I do look at trying to measure and maintain the correct balance between the limbs at brace. You also need to look and think about it with a bow like I'm currently working on, it just may not "measure" out like normal...it's the balance of the bending in the limbs that I think you have to focus on instead of getting caught up in an even dimensional measure. Your full draw may also look different then the normal even sweeping limbs we all strive for if you have a big grain dip coming out of the handle. But they should of course still be balanced when looking at the bending limbs/curvature. Difficult to explain... 

[Postman]

I gotcha, Greg B....
Thanks, all....it turned out to have  about 1/4 inch more height past the BOTTOM dip area at brace,after about 75 shots or so.... about the opposite of what I wanted, but I was happy with the rest of the tiller and the low amount of set she took, and the bow keeping her weight. I think I have my summer stumpin' bow - if the lower limb and overall tiller holds,I'll dress her up in a few weeks. Gotta get a 55-65 pound hunter going- gave all my shooters away in March trying to get my nephews hooked.