Tiller vs nock point

Bill412

Member
I have read on this forum that you can get the same effect on arrow flight by changing either tiller or nock point height. In what sense should tiller be adjusted to get the same effect as raising the nock point?

Thanks in advance for your thoughts.

- Bill
 


geoffretired

Supporter
Supporter
If you turn down the weight on the bottom limb, for example, the bottom limb tip will be pulled upwards by the upper limb, which will now be on a higher setting in comparison to before. The nocking point will rise as the string is moved upwards. You could get a similar effect by turning up the poundage on the top limb. I would not like to guess at how the arrow flight would be changed.
 


Bill412

Member
Hi Geoff, so that sounds like greater tiller raises the nock point. I wonder whether I can find time to make some relevant measurements. It would be interesting. Tomorrow I have a pretty full programme in the garden though. Have to give it some welly. Cheers, Bill
 


chuffalump

Member
Other way round. Tightening the top limb will reduce positive tiller and raise nocking point. Slackening bottom limb will reduce tiller and raise nocking point.

Basically increase tiller and nocking point drops because tiller is positive if top limb tiller measurement is greater than bottom.
 


geoffretired

Supporter
Supporter
Which ever limb you tighten, pulls the nocking point towards that limb tip. That's one way to remember what happens.
Remembering what is "greater tiller" or "less tiller" is less easy to do, I find.
If we say that a bow with two equally stiff limbs creates zero tiller on a symmetrical riser, that could be a starting point.
POsitive tiller is more POpular and results from a stiffer bottom limb. Greater tiller would result from making the bottom limb even stiffer.
Reducing tiller would bring the limbs nearer to equally stiff. And going even further so the top limb is stiffer than the bottom one would be getting into negative tiller.
 


Timid Toad

Moderator
Staff member
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Ironman
But whatever you do won't fix a wrongly positioned np or a badly tillered bow.
 


Bill412

Member
To expand on my original question. I am interested in comparing the following set-ups.

1. I have my bow set up at zero tiller and a nock point height X that gives me unfletched arrows in a group with the fletched.

2. I adjust to maximum recommended tiller, say 9mm for my bow. I then move my nock point as required to get back to a height of Xmm.

Do the unfletched arrows now move vertically relative to the fletched? Which way?

- Bill
 


geoffretired

Supporter
Supporter
Hi Bill412, I see what you are asking about now.heehee.
My guess is that only someone who has tried that will be able to answer it.
I suppose the question could also be... will the same X nock height give the same bareshaft results in the same part of the target??
I would guess the answer is going to be NO. If the answer is going to be YES it would suggest that tiller difference is not that important, so why bother setting a tiller difference in the first place.
I think you can adjust the tiller to something different from your usual one, and adjust the nock point to get bareshafts and fletched to land together again. But I don't think the nock height will be the same as before and I don't think the bow will react the same way either.
 


assybish

Member
Just my 10p worth. I set nock height to get best clearance of tail at standard tiller say 5-6mm depending on riser. Then I fine tune bareshaft into vertical group and attitude at impact ( ie nock elevation same as fletched) using small tiller adjustments. The nock height has to give decent grouping and tail elevation before I use tiller.
 


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