I have come to the conclusion

[Red Tailed Hawk]

That the bows tiller is a liar until after around 300 arrows being shot.

[Steve Milbocker]

On my last one, the sapwood backed osage,the tiller has remained the same. I have 500+ arrows thru it. After each wood removal I exercised the limbs at least 30 times. I'm not an experienced bowyer but I can see that would make a big difference in stabilizing tiller.

[PEARL DRUMS]

Not so. A poor beginning tiller will change in 300 shots. A bow too short and/or narrow for a given design will change. But, if you make a bow with enough wood for its design and tiller it properly. It wont change one in twenty bows. #2 reason is too much moisture in the wood.

[Selfbowman]

I agree Pearl . More than likely moisture if you have built quite a few bows.  Arvin

[Pappy]

With Pearl and Arvin, mine usually never change much if any and the same with most of the guys that build around me.
  Pappy

[Red Tailed Hawk]

Not getting major change. But when I recheck tiller after around 300 shots I do notice a difference.

[Dances with squirrels]

How did it change?

I don't think bows are liars. In fact, assuming there are no hinges or other structural problems, I think the converse is often true... that ultimately, they try to reveal the truth... they try to show how it SHOULD have been tillered/balanced. If a limb is too strong(enough) for the specific way we hold it, eventually it sucombs to us trying to flex it more, and the tiller changes. I think we're often guessing and mistaken on what proper relative limb strength should look and feel like, and this is one of the consequences.

I seem to recall a thread about bows being flipped repeatedly as the tiller incessantly shifted? ...the stronger bottom limb getting weaker each time?

In the end, bows know.

[BowEd]

Ditto on Pearly's comments.Athough if your like me I still try to push the limit too much yet at times.I've got bows here that never change.Even after 1000 or more shots.Honest to God.I store them properly too though.
During tillering like said earlier I torture the pi$$ out of mine and shoot it a lot.It's usually my favorite at first so I want to use it.A bows bad tillering with me will usually show up like you said before 500 shots.
This postive tiller thing used to do it with me.Wanting that towards the end of tillering sometimes it's not excersized enough to show truely the degree of it.It's wood removal and will show up in the end.When chasing my draw weight and bending alike and the way I want it I try to keep my 1/8"to 1/16" positive tiller the whole way during tillering removing even amounts from each limb to my goal.Almost never or rarely does it fail me.That's just my way of doing things that's all,and the way I like it.

[Red Tailed Hawk]

The difference is the upper limb is now bending more than the lower limb. Tiller was spot on. I am thinking that my grip on the bow when shooting is different than the tiller tree and that is causing my issue. Really don't believe it to be a moisture issue. The stave was dry. I probably could have exercised the bow more in between wood removal which could be part of my issue.

[BowEd]

I tiller mine dead center of limb.I really don't think that's it but could be wrong.The rope goes straight up and down.Down the line.I hav'nt seen you shoot either but I bet it's not much different than me.Pulling it to full draw 40 times on tree is usual with me.Got into that procedure while tillering sinewed horn bellied bows.Sometimes they need to be tortuerd a little more to show me what they're going to be.

[BowEd]

My arrow pass is 1.5 to 1.75 above center of bow.

[bradsmith2010]

I don't think there is any set rule,,lots of variables in wood quality ,, moisture etc,, I have a bow I made 20 plus years ago,, it has more set now than then, it was strung all day in harsh Alaska Rain and ocean moisture,, even at night the tent was dripping inside, and that is just one of the hunts in harsh conditions,, so that would fall under the moisture variation,, but that is part of a bows life, I have a black locust from same time and it was not used as hard,mostly target shooting,, it has no set after 20 years,, if you live in a part of the country that is very humid,, tiller can shift a bit,,and I wouldn't consider abnormal,,after break in,, a good bow will stay pretty close,, but keep in mind,, even a fiber glass bow can shift a bit,, sometimes it is not lack of skill or design,,sometimes it is,, it is such a trade off for sure,,,but I agree ,, the more highly stressed design is more likely to shift in harsh conditions,, or more sensitive to over draw,, or shooting 1 million times,, take a well made hickory bow,, and shoot it in the rain for 3 days,,camping out with no indoor relief from the moisture,, leaving strung for 8 hours at a time,, it may shift on you,,

[dragonman]

we talked about this before  Red Tail, my  conclusion was if a bow is near its limits, ie. pushed to the max the wood , design, length etc. can take, then it only takes a few extra long draws, or drawing the  bow in a different way one day, to change the tiller slightly. If the bow is well within its comfort range, this is unlikely to happen... If a bow is poorly tillered this amounts to the same thing.   

I used to push my designs to the limits and this would often happen , especially the bottom limb would change, now I dont push the design  this doesnt happen

[John Scifres]

There is no doubt that a well-used wooden bow will change over time.  I think what Red Tailed Hawk is saying is that a bow is not finished until it is shot in.  For me that is at least 300 shots.  There are just some variables you cannot control during design or construction.  These include unknowable density variations and defects.

Bows have to be designed and constructed for their intended use.  This includes all the variables you can control.  That would include design considerations such as draw length and weight, bow length, width, style etc.  It also includes construction considerations such tillering method and technique, tools, pace, etc.

I have built a couple hundred bows and only now feel confident in my abilities to control variables.

[bradsmith2010]

Beadman I agree about the sinew bows, sometimes you do have to torture the a bit ,, to get them to settle in, ,, seems alot more so than a self bow,,
Yes John the intended use is a very good point,,if the bow is going to be shot in fair weather or indoors,, one thing,, if it will be outside in the elements quite a bit, need to factor that into the design,,, is the bow going to be shot by alot of people,, better consider that,,
is the bow going to an experienced shooter or not,, lots of variable,,
one thing not mentioned, but referred to quite a bit,, sometimes the osage bows pick up weight after some years,, still curing I guess,,