Circular tiller

[DC]

If a bow has circular tiller at say, 20", and then gets pulled to 28" will the tiller still be circular. Just a little tighter circle. My brain says yes.

[Del the cat]

Depends on how long the bow is. If the bow is say 50" long it will prob' effect the tiller. If it's 72" long I'd guess it will stay circular
Del.

[mikekeswick]

Why does it have a circular tiller.... because the limbs are the same thickness. does pulling a bow affect the thickness of the limbs....not much!! So yes

[WillS]

The further you pull a bow, the more the middle wants to bend.  If the tiller is "perfectly" circular at 20", and you pull to 28" you'll see that the tiller is actually weak in the middle.

That's why you want to see different things at different stages.  If you WANT a perfectly circular tiller at full draw, you want to see the middle slightly stiffer before full draw.

[willie]

The further you pull a bow, the more the middle wants to bend.  If the tiller is "perfectly" circular at 20", and you pull to 28" you'll see that the tiller is actually weak in the middle.

I would agree with Wills, presuming a normal bowlength to drawlength ratio, but if you overdraw too where string angles get excessive, it seems that then the tips start coming back more too much.

[DC]

Thanks, good stuff. So I'll think the answer is almost yes

[k-hat]

Seems to me if the bow is within normal desing params (not overbuilt or underbuilt), it stays on a circle, just a smaller diameter circle as the draw progresses.  Ths circular tiller bows I've done had pretty much circular at brace and at full draw.  I would think that a stiff handle may affect that some however. Just another 2¢

[mikekeswick]

The further you pull a bow, the more the middle wants to bend.  If the tiller is "perfectly" circular at 20", and you pull to 28" you'll see that the tiller is actually weak in the middle.

That's why you want to see different things at different stages.  If you WANT a perfectly circular tiller at full draw, you want to see the middle slightly stiffer before full draw.

Not on a rigid handle bow....I presume you are talking about an elb? They shouldn't be circular anyway....

[WillS]

We'll have to agree to disagree on that.  The bowyers I look up to make their heavy bows circular.  And I mean properly circular.  Worldwide distance records don't lie either