# tiller



## Joe T (Apr 5, 2003)

Tiller is the distance measured at a right angle from the string to the nearer side of the limb at the point where it exits the limb pocket. You have two measurements one for the top limb and one for the bottom limb.

Tiller indicates the angle of the riser with respect to the string at bracing height. (or if you like the relative angles at which the limb stubs lie to the riser)If the top limb measurement is greater than the bottom limb measurement (called positive tiller) it means the riser is tilted forward. If the top limb measurement is lower than the bottom limb measurement (called negative tiller) it indicates that wih respect to the string the riser is sloping backwards.
If the two measurements are the same (called zero tiller) the riser is parallel to the bow string.

To move from positive tiller towards zero tiller tighten the top limb bolt and/or slacken the lower limb bolt. Moving from negative tiller towards zero tiller do the reverse. If you only change one limb bolt then there will be some draw weight change. To keep the draw weight the same move both bolts ( in opposite directions).

Don't understand tiller - never came across anybody who did. One of those topics which gets very complicated very quickly. Don't think small variations from zero have any significant affect (e.g +/- 1/8"). Large amounts of tiller I think can cause problems.

Some archers are convinced that certain non zero values of tiller work best for them (may or may not be true - or they may be compensating for their limbs not being equal in strength). Think it comes down to what works best for the individual assuming they can detect any difference.


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## VinZ (Apr 30, 2007)

Joe is correct about the setting of tiller.
Let me answer a few questions.
_Why have tiller?_
The grip of a bow is the center. This means that the arrow is above the center of the bow. Because we have 2 fingers under the arrow and 1 above most pull is underneath the arrow thi means the energy center is more to the center of the bow. This means that risers where the distance from grip to arrowrest is low can shoot with less tiller (Fiberbow is a riser where this distance is the lowest). Barebow shooters that have 3 fingers need a higher tiller to have correct clearance and arrow flight. Because we pull the bow out of center and we want both limbs to work equally the bottom limb has to work harder to make that happen.

_Is tiller important?_
partially yes. an incorrect tiller will cause clearance problems for example(vanes hitting the rest). Nockpoint height and tiller are 2 settings that are related. Having a tiller of 1/4" will make the nocking point height about 1/4" or 1/8" (depending what kind of tuning you use).

_If it is important, how much tiller should I have?_
How much tiller is mostly a personal setting. You can shoot with zero tiller. I would avoid negative tiller, that is hard to tune and not as forgiving. Risers that have a low distance between the grip and arrow rest (like fiberbow, nexus,helix,aerotec) can do with less tiller and subsequently a lower nocking point. Start with 1/4" tiller and use the same for nocking point height. After that start tuning. This tiller and nocking point setting will avoid getting false readings when you start tuning. Because it is a starting point before tuning it is not terribly important what the exact setting is - as long as nocking height and tiller are the same the arrow will not hit your rest and you can start tuning. The fastest and easiest way to do this is bare shaft tuning AND walkback tuning. This means Joe was right when he said "Think it comes down to what works best for the individual...".
I can notice 2 mm (1/12") of change in my tiller or nocking point, the bow just feels different. 

Hope this helps. If you want more information I suggest a hoyt manual. You can download one of them here: http://www.hoyt.com/customer_service/


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## XCalibre (Aug 31, 2006)

thanks. that helps a lot. my nocking point seems quite high, so that's partly why i was asking. the measurements that i just did are as follows: based on the tape measure i was using, my brace height is 9 9/32", my top limb tiller is 7 11/32" and the bottom limb tiller is 7 1/8" (all measured to the center of the string). so i guess that means that i have a positive tiller of 7/32" (just shy of a quarter inch). 

the bottom of my nocking point is 5/8" higher than the center of my plunger button. is it normal to have that high of a nocking point based on the above tiller measurement?

phil


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## VinZ (Apr 30, 2007)

Your brace height works for a 70" bow. Your tiller is correct but I think your nock height might have some work.
Download easton arrow tuning and maintance guide here: http://home.att.net/~sajackson/tuning_guide.pdf
You are measuring you nocking height wrong (look at picture at page 1). There is one easy way to find out if this nocking height works for you: shoot a bare shaft at 18 meter. In Easton tuning guide it is explained what to do next.
After tuning:
setting brace height: shoot at 18 or 25 meters and notice the height of the arrow. Twist (or untwist in your case) a few turns. After that shoot again (do not set your sight). You arrows will go up or down. I think in your case they will go up. untwist and shoot again. repeat a few times. The height where your arrows impact the highest is you brace height sweet spot. After all this: retune your tiller and nocking point...again


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## Seattlepop (Dec 8, 2003)

VinZ said:


> ...
> The height where your arrows impact the highest is you brace height sweet spot....



Wow, that conflicts with everything I thought I knew about selecting brace height and how it affects arrow flight. Mind if I ask where you got this? 

Fred


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## VinZ (Apr 30, 2007)

The first one that told me was the old Dutch Olympic team coach about 1996. I was talking to him when I saw the arrows of Wietse van Alten fly, I never seen any arrow fly so good. I also came across the same tuning methode years later (I think it was archery reference guide - not sure). 
How do you select your brace height?


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## Greg Bouras (Nov 17, 2006)

Seattlepop said:


> Wow, that conflicts with everything I thought I knew about selecting brace height and how it affects arrow flight. Mind if I ask where you got this?
> 
> Fred


Actually that makes good sense and is pretty easy to show. Increasing brace height increases the pre-load on the limbs which results in a greater restoring force of the limb. At the same time the power stroke is decreasing. Since both are bounded it seems reasonable there is a value which produces the largest initial velocity exists.

Next time you are at practice, measure and record your current brace height, sight the bow as usual for say 20 -30 meters.

Now make a brace height adjustment (increase) of ¼” to ½”. Note impact point will be low if you were close to optimal to begin with. Making brace height changes in the opposite direction will decrease will impact high from the increased brace in test 1.


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## Seattlepop (Dec 8, 2003)

Greg Bouras said:


> Actually that makes good sense and is pretty easy to show. Increasing brace height increases the pre-load on the limbs which results in a greater restoring force of the limb. At the same time the power stroke is decreasing. Since both are bounded it seems reasonable there is a value which produces the largest initial velocity exists.
> 
> Next time you are at practice, measure and record your current brace height, sight the bow as usual for say 20 -30 meters.
> 
> Now make a brace height adjustment (increase) of ¼” to ½”. Note impact point will be low if you were close to optimal to begin with. Making brace height changes in the opposite direction will decrease will impact high from the increased brace in test 1.


Yes, brace height affects arrows in the way you describe, but the advise being given says to select the best BH by that which has the most cast, i.e. when the arrows impact the highest. Still think it makes good sense? 

The discussion on brace height in the Easton Tuning Guide is about the best I have found and is what I see most often repeated. I don't see it on their website anymore, but thanks to TexArc you can still download a copy at:

http://www.texasarchery.org/Documents/EastonDocs/completetuningguide2002.pdf


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## spangler (Feb 2, 2007)

Seattlepop said:


> Wow, that conflicts with everything I thought I knew about selecting brace height and how it affects arrow flight. Mind if I ask where you got this?
> 
> Fred


It seems like the optimal brace height would impart the most energy into the arrow instead of wasting it creating things like noise and vibration. Since more energy is imparted into the arrow, it would impact higher.

-Andrew


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## Seattlepop (Dec 8, 2003)

spangler said:


> It seems like the optimal brace height would impart the most energy into the arrow instead of wasting it creating things like noise and vibration. Since more energy is imparted into the arrow, it would impact higher.
> 
> -Andrew


Ah! If everything were as it seems! Yes, quiet is good, but why quiet is good is not related to cast. Check the Easton Guide link above, bottom of p. 10 for a good discussion of brace height. 

TA says what I thought was the conventional wisdom which is that the best brace height is found by sound: "Shoot a few arrows at various brace heights within the recommended range and listen for when the string is the quietest, as this is the point where the arrow nock leaves the string at the right moment."

The Art of Winning adds that better groups are achieved with the right BH. 

I use THA for tuning advice, but it doesn't discuss BH in any detail that I found.

The bottom line is that BH affects cast, but that is not how you find the best setting.


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## VinZ (Apr 30, 2007)

"smoothest and quietest setting" is a very vague concept. When you tune your brace height with 'highest point arrow' methode (for lack of better name) you will notice that the sound is at it's quietest setting. This is because the most energy is put into the arrow and not used for other things - sound and vibration.

I have a real problem with 'the smoothest setting' when tuning. If anyone here can measure the 'smoothness' I will buy him a beer! :darkbeer: (this persoon would have to travel to the Netherlands thou....make it a crate of 24  )
I work with numbers and experimental data, that is something that is repeatable. When tuning from sound you will get a different setting when tuning outdoors or indoors, tuning indoors with carpet on the ground etc etc. But you can hear from the sound a bow makes if it is tuned properly (or good enough).


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## Seattlepop (Dec 8, 2003)

VinZ said:


> "smoothest and quietest setting" is a very vague concept. When you tune your brace height with 'highest point arrow' methode (for lack of better name) you will notice that the sound is at it's quietest setting. This is because the most energy is put into the arrow and not used for other things - sound and vibration.
> 
> I have a real problem with 'the smoothest setting' when tuning. If anyone here can measure the 'smoothness' I will buy him a beer! :darkbeer: (this persoon would have to travel to the Netherlands thou....make it a crate of 24  )
> I work with numbers and experimental data, that is something that is repeatable. When tuning from sound you will get a different setting when tuning outdoors or indoors, tuning indoors with carpet on the ground etc etc. But you can hear from the sound a bow makes if it is tuned properly (or good enough).



I agree with you on the use of the word "smooth". I think its the most over-used and basically worthless word used on this board. I ignore any comment that includes the word "smooth". My second least favorite term is "forgiveness". I ignore that one too. 

However, quiet is not vague. I think anyone can tell the difference between "THWANK"!! and "thmmp". The latter would, of course, be smoother and more forgiving. 

And if I ever have enough money to visit your country, I would be happy to buy the beers!


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## XCalibre (Aug 31, 2006)

well, this thread has taken a little bit of a turn, but not for the worse. since i now have a working knowledge of tiller, that's all said and done and thanks again. 

anyhow, i tried that brace height setting method tonight, but i'm not sure if it worked. i started out at just over 9 1/4", and i increased it all the way to 9 3/4", but by then it seemed that it was quite a high brace height. it almost seemed like i was getting a false reading because my arrows seemed like they still had some height left in them. at the same time, my groups just kind of ballooned. my bow was noticeably quieter though. after taking a short break, i went at it again. this time my group was normal sized, and my bare shafts were still within the group, which surprised me a little. but all my group was back in the ten again, when i thought it was supposed to be higher, so i started decreasing my brace height. right now i'm at 9 1/2", but nothing happened to my arrow height. i was adding/taking off 5 twists from my string at a time. i'll try it again tomorrow to see if i get any definitive results.


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## VinZ (Apr 30, 2007)

XCalibre said:


> well, this thread has taken a little bit of a turn, but not for the worse.


I Agree, it's interesting. A bit more info then you asked for and a real discussion (And the best part - no flames or other insults.)


XCalibre said:


> started 9 1/4" and increased to 9 3/4"
> started decreasing to 9 1/2" - nothing happened to my arrow height
> note VinZ:edited post for readability


That is possible. I already looked up Hoyt/Helix 70" recommended brace height and it's between 8 3/4 and 9 1/4 (source: Hoyt manual 2008). That is the reason I mentioned untwist (decrease brace height) in my second post . Not to worry, we're not going anywhere and keep helping you.
Make sure you check you nocking point. Normally it will stay the same but I've seen limbs where adjusting brace height changed the nocking height.


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## TomG (Dec 4, 2002)

I ahave read this thread with great interest. I like the brace height method. I tried it yesterday and was pleased to find out that my brace height had drifted low and that the test got me exactly were it used to be... That's nice when that happens.

Concerning the tiller. The goal of adjusting the tiller is to have both limbs acting together when you are not pulling in the center of the bow. I have been using a test for some time with great success. It involves masking tape and lipstick. You place masking tape just at the end of the string grooves of the limbs, extending about 4 inches. Apply lipstick to the string end servings were the masking tape is now located. Shoot some arrows. The string will leave some marks on the masking tape. Measure the marks from the limb tips. Adjust the tiller until both marks are equal, meaning that both limbs stop at the same time. Of course you will have to test for the nock point height after each adjustment, as well as adjust the brace height, as they will change when you adjust the tiller.

Let me know what you think.

TomG


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## VinZ (Apr 30, 2007)

That is a nice methode. Would be great to compair bare shaft nock point tuning to lipstick methode. Have you ever done that?


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## TomG (Dec 4, 2002)

Bare shaft and lipstick are independent here. Each time you adjust the tiller you have to bareshaft tune the nock point. For each tiller setup there is a corresponding nock point height. It is very tidious as each time yuou adjust the tiller you have to test everything again before you can proceed with the tiller... But I have seen very good results. The limbs have a lot less oscillations after the shot and the bow feels better.

I talked with Jay Bars at one of his seminars about this and he told me Earl Hoyt did some experiments with tiller and found that it had no impact on group size. The only thing was that each tiller setup had a different nock point height. However there is definetly a difference in comfort. I trully hate when the limbs ascillate...

TomG


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## Greg Bouras (Nov 17, 2006)

In my experience, viewing the bow and arrow from a performance standpoint, say for example highest impact (is an effect) leads one to wonder the cause and is most efficently done by approachingt the thing (system) from a physical standpoint.

In doing so one finds that energy storage and transfer of energy seems like likely candidates are are both something most folks have a good understanding and appreciation for.

That said it would be very difficult to show that the optimum brace height for any set of conditoins can be determined by sound alone. It is true that noise requires an energy source and that energy comes from the bow. Try shooting a quiet bow with a known brace height with an arrow that weights 50 grains less. 

As for brace height adjustments and grouping again the effect is consistent arrow flight. The cause is a stable vibration of the arrow which results form initial loading of the arrow. Brace height is a variable in that relationship.

It is impossible for any particular author to know every readers experience level when publishing their text. Nor is it possible for one author to put everything and explain it so clearly that the discussion stops there.

There is a lot of very good informatoin in print covering every archery topic.
McKinney's book is great and is probably sufficent, however reading everything one can get his hands on is in my opinion necessary.


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## VinZ (Apr 30, 2007)

TomG said:


> Bare shaft and lipstick are independent here.


Sorry :embara: my previous post was incomplete. Didn't ask the question correctly. I was wondering when a bow is properly tuned with bare shaft what will lipstick do?


Greg Bouras said:


> Nor is it possible for one author to put everything and explain it so clearly that the discussion stops there.


There are several ways to do anything, that is also true in archery. So there is always a discussion possibility.


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## TomG (Dec 4, 2002)

VinZ,

Again, the same answer. The two are independant. The goal of the tiller tuning is to have both marks equal. You have to achieve proper bare shaft tuning after each tiller adjustment. 

The final tiller will be influenced by a lot of parameters: grip angle, pressure point in the grip, stabilisation configuration ...

TomG


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## VinZ (Apr 30, 2007)

TomG - We both are saying it correctly. I think we are trying to avoid a long (boring) post. let me try again.


TomGBare said:


> shaft and lipstick are independent here. Each time you adjust the tiller you have to bareshaft tune the nock point. For each tiller setup there is a corresponding nock point height.


In short: Nock point is depended on tiller; tiller is not depended on nock point. 
This means that for every (normal) tiller setting there is a nock point that works with that tiller setting, right? What if you skip the lipstick testing (and just go with ¼ or 1/8 tiller) and go straight to bare shaft for nock point tuning? Will lipstick show afterwards that the bow limbs are in tune? I wanted to test this but found my limbs where cracked (now I know what that strange sound was last friday).


TomGBare said:


> It is very tedious as each time you adjust the tiller you have to test everything again before you can proceed with the tiller...


Right there with you – tuning can be very boring and frustrating at times. Whenever I get strange results I go back to global setting and start over.


TomGBare said:


> I talked with Jay Bars at one of his seminars about this and he told me Earl Hoyt did some experiments with tiller and found that it had no impact on group size. The only thing was that each tiller setup had a different nock point height. However there is definitely a difference in comfort. I truly hate when the limbs oscillate...


True. Tiller is depended on so many parameters like you posted previous. Stabilizers can mask the true oscillation of the limbs and increase comfort dramatically – but lets keep to tiller & brace height. In the old Hoyt manuals there is a little piece about tiller and it being a personal setting. I agree that tiller is mainly a personal setting.


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## TomG (Dec 4, 2002)

> What if you skip the lipstick testing (and just go with ¼ or 1/8 tiller) and go straight to bare shaft for nock point tuning? Will lipstick show afterwards that the bow limbs are in tune?


Did you mean "will the lipstick show afterwards that the bare shafts are in tune"?

Anyway,

In summary here are the steps:
1. Set up bow with standard tiller measurement. Determine brace height. 
2. Bare shaft tune the bow (nock point, plunger)
3. Apply masking tape to the limbs, lipstick to the string
4. Shoot some arrows
5. Measure length of marks
6. Adjust tiller according to difference in marks length
7. Check brace height. Adjust if necessary.
8. Repeat from step#2 untill marks are equal length

As you see the bare shafts (nock point, plunger) can be tuned without the limbs (tiller) being tuned.

TomG


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## VinZ (Apr 30, 2007)

TomG said:


> Did you mean "will the lipstick show afterwards that the bare shafts are in tune"?


YES..that's what I meant. Have you ever tried that? What was the result?
I'm going to test it as soon as I have other limbs (btw: limbs that broke where not my winex).


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