Ok - I am new to this self bow building - so be kind.  Constructive criticism welcome but be kind - my confidence is shaky at best right now.

Example - you suck at tillering is not kind.  

Green ash stave - cut last March - rough cut and drying since.  Began working it this week.  Thought the floor tillering looked ok.  Put on the long string and tillered using a gizmo to 7 inches.  Was looking ok to me.

Made a string and braced her up on the short string to just over 7 inches and this is what it looks like.

I just don't know enough to make an accurate diagnosis.  Is there a hinge on the left limb?  Right limb just way too stiff?  Is there any hope!!!!  

 


Thanks for the help.

Mitch

Looks pretty good if thats your first one,

From my perspective the right limb is still stiff,

I would be working the middle third and the inner third on the right limb.

If those are two inch squares on your board it looks like the right limb can move about that much(2")to catch up with the left.

Hopefully the experts will be along shortly to confirm your work.

Good Hunting

Thanks Mike -

Not my first one - but my first 68" one.  I made a shorter one for practice on a 46" piece of ash that didn't turn out too bad - just too short and light for me.

Yep they are 2" squares.  How much would you scrape to get the right limb to move 2"?  Would you worry about countin scrapes or just scrape a while and then check?

What Mike said, weaken the right limb. Don't worry, my first few bow's looked just like yours:)

You are developing a hinge on the left limb you should correct before stressing it too much. It looks to be between the 2nd and 4th vert line. Get the wood out past that area bending more then scrape the right limb until it bends the same. The right limb looks to be stiff at mid limb mostly.

And make yourself a gizmo.

Mitch, you need to provide us with an unbraced side and back profile pic to accurately assess your tiller.

What you have there is not uncommon when going from a long string to a short string. Happened to me this morning. I shorten my grip up on the limb that wasn't bending nearly enough and gave it a couple extra pulls. That did even things up somewhat but I still had to do a little more scraping to even the tiller out........Art

QuoteOriginally posted by KellyG:
And make yourself a gizmo.

+1 on the gizmo! Right limb too stiff, make a gizmo then use it before going any further, you'll thank us for it later.

Think he said he used a gizmo on the long string, keep using it though to help get them even.
What Pat said about the hinge, work it out then worry about the right limb. Get us some drawn pics, once you have worked on the hinged area. Don't stress it any more than you need to to find out if it is gone.

That doesn't look like a hinge to me. More like a natural kink in the wood. Without an unbraced side pic we're all guessing really....Art

Sorry he did say he gizmoed it. I missed it the first pass.

Thanks guys - I really appreciate the help.

Now to show a bit more ignorance:

Art - I am not 100% sure on what you need for pics (unbraced side and back profile pic) so I added a few...maybe these will help you see whats going on.  Thanks again!

side view unbraced:




Back:




Handle:


Few others:

Pics helped a lot Mitch. Looks like that natural deflex right out of the handle gave you a running start on your lopsided tiller. You could heat bend that area straight to even your tiller back up if you a mind to. Looks like you need to do some heat straightening anyhow.

Since you're using a parallel limb design, you need to match the "BRACED PROFILE" to that. That means the limbs greater bend will be mid-limb or elliptical shaped. Try to keep from mid-limb to tips fairly stiff.....Art

that "deflex" could be set from overstressing the wood too early on.  7" brace is pretty high for a hinge.

Took Art's suggestion and heated the left limb up to straighten it up a bit.  I then did a bit of scrapin on the left limb at mid limb past the "kink".  Then did some scrapin on the right mid limb to weaken it up a bit.

Here is what it is lookin like now.  Art - I just don't know enough yet to know for sure what you mean when you said - "you need to match the Braced Profile".  Are you saying that a straight limbed bow will do most of its bending in the midlimb area?  The tips will be straight with no bending?

If that is the case, the gizmo doesn't really help me much, does it?

Sorry for the ignorance but learning as I go.  Appreciate all your help!!!

Whatever the case, I think it is looking better - I think Art knows what he is talking about!

Mitch

Looking much better but both limbs look slightly stiff mid limb.

Looking good now. Just listen to the gizmo and tiller her out. Post pics often as you go so others can keep you on the right track. I agree with sportHunter work from mid limb out now, but I bet the gizmo shows you that. Good luck.

Adjust your gizmo to the bend of the left limb and use the same setting for the right limb. This will help get them bending evenly.

Overall your tillering looks pretty good just need a little more wood off the right limb.

That parallel limb design that your're using reguires greater bending mid-limb for best efficiency Mitch. And to help hold down limb vibrations, which can lead to hand shock and some arrow speed loss, try and keep the tips fairly stiff.

As Eric mentioned, you need to catch up your right limb. From there, any weight reduction should be done mid-limb to obtain that needed elliptical limb shape (then your braced profile will match your chosen limb design for best efficiency)........Art

Thanks for the suggestions guys - will do as Eric/Art suggest.  Will have to wait - got to get to bed early tonight.  My cousin who lives in the southern part of the State lined up some places for me to come cut some osage early in the morning.  Almost as exciting as the night before opening day of bow season!!

Mitch