first R/D BBH Tiller help -UPDATED-

[silent sniper]

Hello everyone, I need some suggestions on this bow. I built it following Dean Torges video, hunting the bamboo back bow. The bow is made to his specs, except the belly is straight quarter sawn hickory instead of osage. The Bow is 1.25" wide at its widest point, and the top limb is 1.5" longer then the bottom. As it sits it holds around 3" reflex when unbraced. My problem is i just can not figure out what to do the tiller. This is my first R/D bow and i just dont know what to do.  Please help me settle this thing out! Thanks, SS

longer top limb on the right side in pictures..

Unbraced:


low 4" brace:


drawn to 22":

[bow101]

Hinging right out of the gate.   You could try gluing a lam on the back to stiffen it up; if possible. 

[Pat B]

To me your initial shape is flawed. I don't build R/D bows because they are hard to read the tiller but I think your reflex is too concentrated to one area and the deflex is too extreme for the overall side profile of the bow.
Also, 1.25" is too narrow for a hickory bow, adding bamboo increases the stress and making it a R/D you add more stress.

[BowEd]

silent sniper.....I too have Deans' form here.Done some BBO's with it.If like mine your deflex block is for hunting bows it's closer to the handle and a real bugger to tiller.The target deflex point towards the tip more is easier to tiller.
Like daid you deflex in handle is too much.
To tiller your bow you'll have to slowly remove material midlimb till you can at least get it straight.Very touchy.Going past that will be bad.Very slowly little by little reduce this.Your material may be tough enough to handle it.Last one I did was from a maple baclked red cedar and it chrysalled all to heck right at the hunting deflex point before going into a reflex.

[GB]

I agree with Pat that it looks like the deflex is too abrupt and making the limbs at least 1/4" wider would have been better.  I'd follow Ed's tillering advice and finish tillering it, carefully working the midlimbs.  If it winds up much lighter than you wanted, you can always cut the handle off and glue either a power lam or full length one to the belly and retiller.  I had fits tillering my first BBO and when I finished, most of the bending was right at the handle fades.  I cut the handle off, glued a long power lam on, and retillered it.  It took more set than it should have from my mistake, but turned out to be a really nice shooting bow.
I've only made a handful of R/D bows and am certainly no expert.  They do seem easier to tiller when I move the reflex posts out closer to the tips.  That spreads the deflex out, too.  I start my rasping midlimb and stay away from the handle fades until I get the mid and outers bending.
I'm sure there are better examples on here, but this is the profile of the last BBO I made.

[Badger]

  Pat B and GB nailed it. Several problems with the bow, I would scrap it. Bad shape to start off with. Too narrow for that design. Look at the profile on GB bow, thats ideal or very close to it for an r/d. Too much bend in the center of the limb is a nightmare to tiller.

[silent sniper]

Well I just couldn't scrap the bow with so much time invested in it. I decided to work it out and see what happens. I have really worked down the heavy deflexed areas to help even out the bow and keep the pressure off the fades. The hickory core is still looking good with no fretting yet....  The tiller is not perfect but I think it is coming along.  I have it at a 6-6.5" brace height and full draw around 28.5 inches. Please let me know what you think.  Thanks SS

Bow is slightly canted in the full draw photo



Full draw


Just unbraced

[Knotty]

It's definitely alot better, the full draw looks great, the braced profile.. Not too much 😞.

But well done, next time remember to carefully measure all reflex and deflex you add .

[ajooter]

I admire your persevearance....way to make a bow!  Im sure the next one will be better.  This hobby def has a learning curve!