question on tillering

[arrowlauncherdj]

guys I am trying to tiller for 3 under on a new curve I am making. Traditionally some bowyers just do even tiller, some dont change from 1/8 stiff on bottom as they would for a split shooter.  My question is, what if I made the upper limb a bit stiff? like 1/8"?

Has anyone ever done that and what effect did it have on the action of the bow.  I would assume it would make you have a lower nocking point, but are there any no no's to doing that?

Dave

[Sam Harper]

I vaguely remember somebody somewhere saying that they do a negative tiller, and he had some explanation for why it was better.

The bow will still shoot.  It just that there's a sweet spot when it comes to where your arrow shelf is, where you pull the string from, and what kind of tiller you have, and when you get that magical sweet spot, the bow will make very little noise and have almost no hand shock or vibration when you shoot it.  Whatever that combination of factors happens to be, so be it.  People generally do the even tiller for 3-under and 1/8" positive tiller for split finger because, on average, that's supposedly what results in the sweetest shooting bow.

I was at a shoot a few months ago, and I overheard this guy talking about how after he finishes tillering a bow, he'll shoot the arrow from various heights in relation to center to determine where it shoots the sweetest. Then he cuts his arrow shelf there.  I suppose you could do the same thing.

I suspect that if you make the top limb stiffer, you'll have to raise your arrow shelf a little to get it to shoot sweetly.

But I personally have a hard time telling the difference in vibration when I shoot the same bow split fingered, then 3-under.  Maybe other people are just more sensitive to that than me.  I dunno.

[Bowjunkie]

I tiller my bows so that the limbs are under equal strain at full draw, while held the way I hold them. Depending upon a variety of factors, when finished, some bows end up tillered positive, some even, and some negative... like you're describing. When timed/balanced as such, there are no negatives. Things work out for the best all the way around... no tiller shifts, less vibration, handshock, noise, bows are inherently tuned, no need to move hand placement or nock points, etc to find the sweet spot. The sweet spot is right where I put it.

I don't tiller to any predetermined brace height measurements. I balance the bow at full draw and let the braced profile be what it will be. Some folks have a hard time with this... trust issues perhaps. They must have an arbitrary number as their goal from the onset. It's too bad really.

The only "no-no" I can see in your scenario is if you tillered it to be 1/8" negative (greater distance in the bottom limb measurement) and that wasn't what it actually needed to balance limb strain relative to your holds on bow and string... then you could have done a little better, that's all.

[arrowlauncherdj]

Thanks guys. Ill give it a shot and see

Dave