Have a question Guys about tillering

[Art B]

Bowjunkie,the only thing that I can think of that would cause the distance between A and C to be that close is if the arrow pass and string nock is center of the bow. That would place the bow/drawing hand below the dimensional center of the bow causing greater strain on the lower limb. Here, even limb mass would be ignored, causing timing/balance problems.

Concept of even tiller is based on the fact that the drawing force of the hand is more in line with dimensional center of the bow (arrow pass above center). And gripping the bow so that even strain is applied to both limbs and both limbs having equal mass for best timing/balance.

So, if the drawing force "C" is center of the string, bow hand center of the bow, how can the lower limb be more strained over the upper limb? It can't, because both limbs receive equal strain.

What am I missing here?          Art

[Art B]

Originally posted by Roy from Pa:
 
And the other thing I wanna know is, should I pull the bow from the center of the handle on the tree, or should I pull it from the top of the handle, which is closer to where I will pull it when shooting it .

I think, if what you were previously doing (pulling from the top of the handle) was working for you Roy, you wouldn't be asking this question........Art

[Roy from Pa]

It was working Art, but I noticed most all of the guys on here pulling from the center, that I thought I could be doing it wrong.

[Art B]

I use to pull from the top of the handle also Roy. Only because of the recommendations of a some folks on these boards. First thing I noticed was that most of my scraping/reduction was being done on the lower limb to maintain an even tiller as the bow progressed to full draw. Perhaps you've noticed this too?

I like to ask questions, so I asked myself why was this happening. To use Bowjunkie's illustration, reverse it, and using A as the upper limb, you will notice the upper limb with a tighter radius. To even out tiller and catch up the bottom limb (A), it must be scraped more.

Sure, you can make this apporach work. But by pulling closer to center you not only keep the limbs more evenly strain during the building process, but even limb mass is better maintained.......Art

[Bowjunkie]

Guys, I edited my post above after some more thinking and testing. Please revisit it and let me know your thoughts.

[Roy from Pa]

Well if the top limb comes around sooner when shooting split finger, then why would anyone want a positive tiller on the top limb? And for 3 under shooters, it seems they would need a less positive tiller than split? I'm more confused now than before:)

[Bowjunkie]

"Well if the top limb comes around sooner when shooting split finger, then why would anyone want a positive tiller on the top limb?"

Bingo! That's the million dollar question. Because they're doing what they're told instead of taking the time to test it themselves. Not everyone follows those guidelines, Roy.

I watched, and fought, what was happening on my tillering tree in denile for a long time.

"And for 3 under shooters, it seems they would need a less positive tiller than split? I'm more confused now than before:)"

No, more positive.... or, a stronger bottom limb, relatively speaking.

[Bowjunkie]

Here, read this.

 Tillering the Organic Bow

[Art B]

Yeah, I use to be stuck in that same logic Jeff, but since moved on. Keep testing.......Art

[Art B]

Roy, the top limb comes around quicker ONLY on the tillering board (when drawn closer to the top of the handle). Not while the bow is actually being shot. That's where the confusion is coming into play.

When the bow is being drawn on the tillering (again, when drawn from the top of the handle) board the top limb receives the tighter radius.

When the bow is being drawn by hand (using split fingers, bow with positive tiller), the tighter radius shifts from the top limb to the lower limbs BECAUSE of the hand/heel pressure.

That why the tillering tree has been described as the lying tree. If you strictly use a tillering tree to set the bow's tiller then you get what Bowjunkie prescribed.  

Do a search for "tillering for three under". Lots of reads and opinions. Here's a few:

http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=100511

http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=098117

http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=search_tng;d=results;record=2455686-142653-GY9N;result_start=20

http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=083262

http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=077022

http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=075748

[vanillabear?]

[Roy from Pa]

Roy, the top limb comes around quicker ONLY on the tillering board (when drawn closer to the top of the handle). Not while the bow is actually being shot. That's where the confusion is coming into play.

When the bow is being drawn on the tillering (again, when drawn from the top of the handle) board the top limb receives the tighter radius.

When the bow is being drawn by hand (using split fingers, bow with positive tiller), the tighter radius shifts from the top limb to the lower limbs BECAUSE of the hand/heel pressure.

So therefore Art, that's why one should pull the bow at the center of the handle on the tree?

[Art B]

That's one reason Roy. You can't accurately mimic one's draw on the tillering board when using the split finger draw. But at least you're maintaining even limb strain, and just as important, at least to me, is maintaining equal limb mass.........Art

[Bowjunkie]

Roy, like I said before, the bows themselves are the best instructors. When you have serious questions, don't blindly take someone else's word, including mine. Get off the computer, get out to your shop, and study, test, learn, and adapt. People can get confused, bows generally can't. The bows, they have the correct anwers. Let THEM teach you.

"Roy, the top limb comes around quicker ONLY on the tillering board (when drawn closer to the top of the handle). Not while the bow is actually being shot. That's where the confusion is coming into play."

Yes, it CAN be confusing, but it doesn't have to be. The reason that problem 'seems' to go away is because the bow hand is flexible and allows for the shifting fulcrum. I'd rather that didn't happen however, because other problems can come with it, and work to avoid it as much as possible.

"When the bow is being drawn by hand (using split fingers, bow with positive tiller), the tighter radius shifts from the top limb to the lower limbs BECAUSE of the hand/heel pressure."

I don't know about that, but if so, I'd rather that didn't happen either. That sounds like a good reason to draw the bow from as close to its center as possible. i.e. asymetrical limb design.

"That why the tillering tree has been described as the lying tree. If you strictly use a tillering tree to set the bow's tiller then you get what Bowjunkie prescribed."

Perhaps some don't have it set up as well as they should, misuse it, or misinterpret it, and then make judgements based on the resulting bad information.

I make my final assessments by hand as well, but careful use of my tillering tree invariably gets me right in there with no surprises.  

"You can't accurately mimic one's draw on the tillering board when using the split finger draw."

Well, we can sure do a lot better than drawing it with the hook in the middle of the handle :^)

later dudes, I have lots of sanding to do.

[hova]

i always used a hook loop so i wasnt constantly rubbing on the string. i gave my tillering stick a fulcrum as well and always made my bows so the middle finger is the middle part of the bow. tiller to 2-3 close like everyone else and see where youre at in a mirror.


good luck...

[Lee Slikkers]

gosh, after reading this I am hessitant to even trust me eyes or the Tiller tree       I guess more bow breaking an d hands on learning time will have to provide this Newby with the answers I seek...

[George Tsoukalas]

Lee, don't be hesitant at all. Make shavings. Tillering for the first time can seem to be daunting but with time it gets easier to get a bow. Do it. Check my site. Jawge
http://georgeandjoni.home.comcast.net/~georgeandjoni/

[Roy from Pa]

Don't be scared Lee. If Art and I can do it, then any one can do it:)

[red hill]

Thanks for the link above, bowjunkie. Dean's explanation is very good.
Stan

[Lee Slikkers]

Thanks guys...not saying I CAN'T do it just that I'm right on the cusp of doing so and heading from the floor tiller and long string to a short string this weekend.  Since I'm sneaking in on the more critical steps of tillering and finding the bow I and just get a bit nervous about the process and hopefully not missing any major step or doing this incorrectly.

Anyway, great topic folks!