Bow set up, top/bottom limb tiller, ANY bow, how much does it matter……?

[JohnnyBa]

In my chase for consistent shooting, it was mentioned about my bows tillering and my choice of shooting style, split or 3 under. A bow is purchase off the shelf, any bow from any bowyer, what is the difference going to be when choosing 3 under or split? What is it the archer can do to change the tiller if the bow. Not really sure if that is even anything to worry about unless you are chasing Gold at the Olympics, I mean seriously? I can see a bowyer making a bows tiller “custom” for a particular archer but how is this achievable to off the shelf bows, from a cheap china bow to any pricier model one piece? I see that ILF makes this possible but what about other bows with out that adjustment feature? Surely we aren’t supposed to take files and sandpaper to brand new bow limbs? Is it really that important or is it just something “perfectionists” desire.  Things that make you go “hmmmmm”, or is it just me?

[PrimitivePete]

I would add that if I needed to modify a bow to make it shoot consistently either 3under or split, then I don't want that bow period. The best bows I have owned only required a small modification in nock height to accommodate the change. I 'd rather worry about arrow choice.

[Fireman2019]

You can raise the nocking point a bit for an even tillered bow. I switched to three under and raised it a bit on my black widow. My bow is back in Nixa getting some weight shaved off the limbs and they are going to to tiller it 3 under. My Stalker that is currently being built is tillered 3 under. There are some cheaper and older bows that can’t handle the repeated stress of three under shooting. I don’t think it makes much of difference on todays bows. You can raise your nock until your arrows fly correct.

[Terry Green]

Hello Johnny,

Bows with normal - top positive- tiller are that way for split.

If you shoot those bows you can experience noise, limb vibration, hands shock.  Not sure you could shoot the difference in the accuracy department.

If you do order, and you shoot 3 under as you do, then you would shoot one tillered for such to avoid all of the above.  Unless the bow's design includes them from the get go.

Stay after it... remember, no monsters. 

[McDave]

I think the answer is that if you have a choice, by all means have the bow tillered to suit your shooting preference.  If there is an off the shelf bow that you want to buy, it will most likely be tillered for split, unless it is ILF.  For an inexpensive bow, I wouldn't worry about it.  I've bought a number of inexpensive bows over the years for teaching purposes, grandchildren, etc., and have never found one that couldn't be used 3 under with a small nock adjustment.

Higher priced bows are built for performance, which means the tolerances are a little closer, and it is more likely that you will notice if the tiller is off.  I wouldn't buy a high priced bow unless it was tillered 3 under, an ILF, or I had the chance to shoot it to be sure that however it was tillered, it would work for me.

[Orion]

If using the same form, bowyers adjust tiller by adjusting the thickness and/or taper of the laminations in one limb vs the other.  At least that's what they say they do.  Some just sand one limb more than the other after the fact. 

Folks get all bent out of shape on the tiller question.  Tillering is shaping the limbs so they bend as close to equally as possibly as the bow is drawn and comes to full draw.  A 3/16-inch difference between split (3/16-inch positive) and 3-under (even) tiller (which is the standard/normal difference) makes no practical difference. As others have pointed out, a slight adjustment in nock height evens things out.  In a lot of instances, how a shooter grips the handle and/or the string has a bigger influence on tiller than how the bow is constructed.  Unequal, weird distribution of pressure on the riser and/or the string fingers can make more than 3/16inch difference in the bow limb dynamic tiller.  It may also require an unusual nock height regardless of how the bow is tillered for that particular shooter.   

With an ILF rig, of course, one can adjust the limbs rather than the nock point to get the same effect, and because there is greater adjustability (i.e. negative tiller) it's possible to accommodate unusual grip and/or string hand pressure/torquing of the string.  Builders of one- and three-piece bows could build negative tiller into their bows for 3-under shooters, but most don't because most shooters wouldn't know how much negative tiller to ask for because they've never determined the amount of negative tiller (if any) that is best for them. Only an ILF shooter can do that.

IMO, the psychological effect of tiller has a greater effect on shooters than any practical effect. If folks think they can't shoot a bow as well tillered one way vs another, they won't.  OK, I'm open to flaming now.

[JohnnyBa]

Very well said and passed along so I can even understand! Thanks for all inputs, more learning for me!

[Terry Green]

From the late great Dean Torges.....

http://www.bowyersedge.com/organic.html

[Friend]

Plenty of valued advice...

[Bamboozle]

That's really good stuff from Dean.  I remember a thread a year or so ago here a member posted here and on another forum.  Everything here was spot on, on the other site someone that couldn't carry Dean's quiver said it didn't mater that Dean was just OCD.  Dean was not OCD, he was a perfectionist.  Big difference. He was a master custom furniture craftsman, and his bows were no different.  When you held one of his bows you were holding perfection.

BTW, you can download his book here also.

https://digitalstore.tradgang.com/

[MCNSC]

I shoot split finger . One of the best shooting bows I’ve owned was a used BW that was tillered for 3 under.

[Kirkll]

From the late great Dean Torges.....

http://www.bowyersedge.com/organic.html

If you have the time and patience to read Dean Torges whole article there is a lot of good info and is mostly centered around “Organic” bows….but a lot of this won’t mean much unless you build bows yourself.

   As a glass bowyer of 15 years I can tell you that the same principles apply to modern laminated limbs too, to a certain extent.

  Dean does a great job of explaining how the tillering process works and that it’s more about limb balance, and where the limbs are balanced and where they are bending that matters and changes the WAY a bow is tillered. But How the tiller design and and balance is achieved is quite different on laminated glass bows.

The limb design shape,  taper rates, and width profile all dictate where the limbs bend for the most part on laminated glass and carbon backed bows.

I’m not going to write a long explanation of the procedure…, but…A custom bowyer can alter the overall tiller and the balance just like a self bow or wood bow. It can be manipulated during the lamination process by shifting wedges and changing taper rates to the same limb shape, or design. Contrary to Deans philosophy , It can also be fine tuned by sanding the glass to a certain extent…. But knowing WHERE to sand the glass is critical.

With big companies that mass produce limbs, and even a lot of smaller bow shops, they rely completely on the symmetrical lay up and are rarely balanced.

This is important…..

You can sand the glass on limbs to change the tiller measurements…. But unless those limbs are bending exactly the same top and bottom as you draw the bow, it will make very little difference. Mapping the limbs on butcher paper is the only way to check your limb balance.

Bottom line is tillering for 3 under or split finger is not even worth talking about . Very few archers could tell the difference in a plus or minus 3/16” tiller measurement. Adjusting your grip and nock height on the shelf is all you need to adjust.


As a bowyer….. unless you start talking about balancing a bows limbs to the pressure point on the grip, the tiller measurements are just reference points to be used when fine tuning.


.02 cents….    Kirk

[GCook]

If tiller was a non issue it wouldn't be one of the big pluses of an ILF rig. 
Can a nock adjustment allow you to tune and shoot well?  Yes.  But it also changes the resonance sound of the bow.  How much, to what extent, will vary but it does affect sound.  Not necessarily a game changer or deal breaker but it can be.  Noise makes a difference for me. 
Also mention to your bowyer if you use a fixed crawl.  A whole other can of worms.

[McDave]

Another thing that can cause a problem is if the bow is tillered to shoot from an elevated rest and you try to tune it to shoot off the shelf.  I just about tore my hair out trying to get rid of a persistent nock high.  I finally tried so many things that I half convinced myself I had forgotten how to shoot a bow.  So I broke out my trusty Bob Lee, which only has a shelf, and shot a bare shaft, which shot perfectly, as always.  The next day I was driving around and it finally occurred to me that the problem might be caused because bow was tillered to shoot off an elevated rest, so I put one on and it bare shafted perfectly.

The thing that made me write this post was GCooks comment above about tuning for a fixed crawl.  I have done that a time or two, and what usually happens is that if the bow is tuned to shoot when gripped at the arrow nock, the bare shaft flies nock low when gripped lower on the string at a fixed crawl position.  In my experience, if you raise the string nock a little, you can get perfect bare shaft flight when using the fixed crawl.  But then it isn't perfect anymore if you grip the string where the arrow is nocked, so you get your choice.

The interesting thing about my case was that I couldn't eliminate the nock high when I gripped the string at the arrow nock, but when I gripped it an inch or so below the arrow nock, where a fixed crawl grip position might be, the bare shaft flight was perfect.

Once I knew what the problem was, I was able to solve it so I could shoot off the shelf by a combination of building up my shelf a little to bring it closer to the elevated rest hole, and increasing my positive tiller.  I didn't have to raise my shelf very much, about 1/16”, and I ended up with a positive tiller of about 3/8”.  It took quite a bit of mental gymnastics to convince myself that I needed to increase positive tiller on a bow that I  shoot 3 under, but the reason I needed to increase positive tiller was the opposite of the reason why it is sometimes beneficial to increase negative tiller to tune for a fixed crawl.

It is interesting that I haven't had a similar problem when tuning a bow that was tillered to shoot off the shelf that I wanted to shoot off an elevated rest.  Don't know why there would be a problem going one way but not the other.

[hvyhitter]

Ive shot 3 under for about 30 years now and with a few dozen bows. I've found that its a matter of just tuning every bow with the specific arrow combo that matches that bow. I've 3 keeper longbows and 5 keeper recurves that I've been shooting the last dozen years or so. I think that only 1 longbow and 2 of the recurves are supposed to be tillered 3 under, yet all have a nock point 5/8 - 9/16 and shoot great. Its all a matter of nock height, brace height, arrow length, arrow spine, and point weight. I set the nock point, then brace height 7" for longbows, 8 1/2" recurve, pick arrow thats close, then tune like any other bow for good arrow flight........