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Question about floor tillering and making target weight with heavier bows

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Sandsquid:
I've been trying to make a heavy weight ELB for two years now.  I've had some success with bows under 100 lbs, but can't seem to get north of 100 lbs without the bow taking a large amount of set.  The bows I've made have held together they just are not very fast shooters.  I've feel my failure begins when I first try to brace the bow.  I've been a bad judge of where I'm going to end up in lbs.  I feel by trying to brace a bow that is way over target weight I'm putting unnecessary strain on the limbs.  My successful bows under 100 lbs were mistakes.  I was tricked by the reflex in these staves.  These bows were real stiff until I braced them.  Once braced they lost weight quickly.  They did manage to hold some reflex and seem to be fast for their weight (at least compared to other bows I've made).

At the moment I'm working a piece of white mulberry.  This is my first time working with this wood.  The stave had a slight propeller twist, reflex/deflex in one limb, deflex in the other, and decent size knots on the inner 1/3 of each limp.  I've steamed every thing mostly straight and plan on heat treating the belly.  The handle is 1.7" wide by 1.15 thick.  NTN will be 76" (I would have liked it to be a little longer but my dad cut the log a little short).  I'm shooting for a final weight of 120-130 lbs @ 30".  I have each limb bending 8" and everything looks pretty even on to me on my tillering tree.  At this point the stave has taking about a 1/2 inch of set.  I think I'm going to heat treat now and let it sit a few days before moving forward.  I just hate to make the same mistakes again.

Does anyone have any tricks for making target weight for these heaver bows?  Any suggestions on methods for getting the bow to a brace?  Does anyone have experience with mulberry in heavier weight ELB?  Any advice would be appreciated.

Pat B:
Looks like your right limb is bending more than the left and most of the bend is at mid limb.
 You might also post this in the War Bow section. You will get more and better advise there because those guys are more familiar with tillering heavy ELBs.

Badger:
   You don't have to guess at it at all. When you are tillering the bow and using the long string read it just as if the bow were braced. It does not change much when you brace it. So if you want 120# @30" then pull the bow to 120# each time and just keep correcting the tiller until you get to 28". Once you get there you can brace it and finish tillering. If the bow starts taking too much set on the way you will need to lower your target weight.

bradsmith2010:
maybe you will need to use more wood if the bow is taking  too much set,,wider longer, etc,,

willie:

--- Quote from: Badger on September 08, 2022, 05:28:37 pm ---If the bow starts taking too much set on the way you will need to lower your target weight.

--- End quote ---
or

--- Quote from: bradsmith2010 on September 08, 2022, 10:20:23 pm ---wider longer, etc

--- End quote ---
or
lesser draw length
or
use a more elastic wood

the above covers the design possibilities If your bows are taking their set evenly all along the limb. If not, try tracing the rested limb as you tiller to in order to locate your problem areas as they develop.

how much set would you be happy with for a 77" bow? 
a pic  of an earlier bow at full draw will eliminate some guess work by others commenting

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