Tiller Help Please!

[ajbruggink]

Heh guys, I'm working on my first narrow handled, wide limbed bow and I am having some problems with tillering it to say the least. Right now I am at the step where the string is strung so there is no slack, 11 inches (27.94 cm) down, and I think that the bow is bending way too much near the fades. I have been removing wood from the limbs, figuring that if the limbs are bending too much at the fades, they are not bending enough everywhere else but I can't get the tiller to change, I keep removing wood and checking the tiller and it has remained the same. I have to know what I'm doing wrong, because obviously something is wrong with what I'm doing. Your advice and critique is greatly appreciated.

Thanks,
Aaron
 

[occupant]

I can't see the top picture that well, but it looks fine so far.

[burchett.donald]

   Aaron, from the picture above everything looks great...Looks like a nice even bend throughout...I would like to help, what makes you think there is to much bend in the fades.

   What type of wood are you using?
   What are your bows dimensions?
   What weight are you going for?

    From the side view the limbs look to be around 3/4" thick, kind of heavy...I can't see where your doing anything wrong as you stated, be patient it will move/bend.
                                                                                                              Don 
                                                                                                                                       

[ajbruggink]

I apologize for the small picture, I'll put up a larger one.

[Pat B]

Are you exercising the limbs after each wood removal?  This will help for the wood removal to register.
 Your limbs do look a bit thick still so keep removing wood and exercising the limbs are eventually they will come around.
Leave the area near the fades alone and just work the rest f each limb. Once the limbs start bending better and everything is even you can always bring the bend back into the fades. The fade area has the most stress because of the leverage of the limbs so if you get them bending too early you can cause a hinge.
 Do you have one of Eric's Tillering Gizmos? If not check out the "How To" section where he has instructions on how to make one.

[ajbruggink]

I hope this helps. I felt that the wood was bending too much near the fades because I thought that narrow-thick handled, wide limbed bows like this needed to be stiff in the middle and bend at the mid-limbs. I probably didn't word that well, but this doesn't look like the tiller examples in TBB vol I to me. As for the type of wood, this is a hickory-backed red elm board stave I glued up, my bow's dimensions are 66" long, handle is 1" wide, it has a width of 1 7/8" at mid-limb where it tapers to 1/2" nocks, initially I started with a thickness of 3/4" but it was taking a long, long time to floor tiller that thing and I could not get it to bend in the lower limb, it wanted to bend near the handle, so after 2 hours of this, I made a gamble and decided to taper the stave's thickness from 3/4" just off the fades to 5/8" at mid-limb, to 3/8" at the tips and I was finally able to get it to bend more in the middle and lower limb instead of near the handle. The two bows I made before this barely needed floor tillering because I made them from dimensions off an artifact. The problem with that approach is it is hard to reach a specific draw weight and I wanted this to be a 55 lb draw bow. I don't know if I'll reach that now, but I've heard to hit a specific draw weight its easier to make a bow heavy, make the tiller right, get your draw length, and then you can remove wood to reach your draw weight if need be. If I'm wrong in any of this (I probably am) please tell me. 

Thanks,
Aaron

[ajbruggink]

Are you exercising the limbs after each wood removal?  This will help for the wood removal to register.
 Your limbs do look a bit thick still so keep removing wood and exercising the limbs are eventually they will come around.
Leave the area near the fades alone and just work the rest f each limb. Once the limbs start bending better and everything is even you can always bring the bend back into the fades. The fade area has the most stress because of the leverage of the limbs so if you get them bending too early you can cause a hinge.
 Do you have one of Eric's Tillering Gizmos? If not check out the "How To" section where he has instructions on how to make one.

Yes, I am removing wood after each wood removal. I'm divided on how many times I should exercise the stave, I may have made the mistake of reading too many different bowbuilding books, one says to exercise the bow 30-50 times after each wood removal, I believe I remember TBB vol. 1 saying exercise the bow 10 times, and another I've read said 20 times. I've been doing 20 times because it seemed like the happy medium but I'm beginning to suspect that it isn't helping much. They gave us off Christmas Day through the weekend (I just got done with my Christmas Eve work day as I am a 3rd shifter), so I may have to check out this tillering gizmo. Thanks, Pat.

[bubbles]

20 to 30 pulls is what I do.  You still got quite a ways to go. I wouldnt get too hung up on tiller shape this early in the process. Its not going to start looking like a finished tiller until you get the bow braced and out to 20+ inches of draw. Just concentrate on an even bend, and avoiding hinges, and like Pat said, go easy on the inner limbs.

[burchett.donald]

  Aaron,
            Yes on that stiff handle flat bow you want the fades to work/move, you will have to balance it all out as you go. I leave only the handle and limb tips static. Right now you need to get those limbs bending enough to low brace it. Staying on the long string to long will give you a false read and cause you to undershoot weight more than anything. When I say false read it could be the weight or tiller...Once you get it braced you have the limbs at a different force/pulling against each other and then you will see your real tiller.
                                                                                                                     Don

[PEARL DRUMS]

Here is my opinion. If that is as far as you can safely pull it, then you should still be floor tillering. If you cant flex the limb tips at least 8-10" on the floor, then you aren't ready to put it on the wall with a string. That will only cause you to pull it farther and farther trying to see subtle differences on a limb that is barely moving. By the time you recognize something is amiss, its too late. A good floor tiller is what creates very low set bows in whatever design your making, in my opinion. Plus floor tillering practice will never hurt a bow, just keep at it until that limb arc your looking at down your leg is perfect. Brace it so the string just misses the handle and continue tweaking to weight and draw length, like you already started.

That's my .02 cents for what its worf.

[Springbuck]

  I don't know if this helps, but with a bow like that, I start out wanting to see bend right off the fades, but only at a few inches of draw.  I work the limb down evenly in thickness until I get the first 25% of each limb bending first.  Not enough to take set, though.   Then it is easy to sort of chase that bend outward along the limb, smoothing it  into a nice arc as you do.

Yes, the middle 50% or so of a flatbow limb should be bending most, but esp because of the narrow handle/fades, the whole limb needs to be doing it's share.

[George Tsoukalas]

I like the bend to almost always start at the end of the fades. Mark with a pencil where bending should begin. Jawge

[bubby]

Here is my opinion. If that is as far as you can safely pull it, then you should still be floor tillering. If you cant flex the limb tips at least 8-10" on the floor, then you aren't ready to put it on the wall with a string. That will only cause you to pull it farther and farther trying to see subtle differences on a limb that is barely moving. By the time you recognize something is amiss, its too late. A good floor tiller is what creates very low set bows in whatever design your making, in my opinion. Plus floor tillering practice will never hurt a bow, just keep at it until that limb arc your looking at down your leg is perfect. Brace it so the string just misses the handle and continue tweaking to weight and draw length, like you already started.

That's my .02 cents for what its worf.
X2 great advice

[Loope]

If I understood correctly, you were asking if the way to tiller the bow was to first get to draw length with a good tiller shape while maintaining a heavy draw weight, and then gradually remove wood to get to target weight.  This is generally not the method used.  I think most people here would tell you to never draw more the bow heavier than your final target weight.  The better process is to pull to bow to your target weight each time, observe the tiller, and gradually remove wood until you reach your target draw length.

[ajbruggink]

If I understood correctly, you were asking if the way to tiller the bow was to first get to draw length with a good tiller shape while maintaining a heavy draw weight, and then gradually remove wood to get to target weight.  This is generally not the method used.  I think most people here would tell you to never draw more the bow heavier than your final target weight.  The better process is to pull to bow to your target weight each time, observe the tiller, and gradually remove wood until you reach your target draw length.

Yeah, your explanation sounds better, my explanation would cause set. I was just trying to say its hard to get a specific draw weight by having the thickness already cut out, if that makes sense. Thanks for the reply.