Primitive Archer
Main Discussion Area => Bows => Topic started by: Louie on February 06, 2018, 02:16:24 am
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Hi Guys
So the bowyer bug has bitten and I'm on my second bow. I'm busy with a hickory backed ipe 68" ntn 35mm wide at the fades and tapered to just under 1/2" at the tips. I'm looking to reel in 40# @ 27".
So here is my dilemma, when I look at the bow at 22" draw the right limb seems to be stiffer. No problem. Then I flip the bow around and, well, now the right limb seems stiffer (obviously I'm now looking at the previous left limb). Do you guys suffer from this optical illusion sometimes? I know the bottom limb needs to be slightly stronger than the top and at full (fist melee) brace the positive tiller measures in at 1/4".
I'm close, its really just a slither away and I really don't want to miss my target draw weight by removing shave after shave and this illusion just wont go away.
What would you do?
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Why do you call it an optical illusion? Is the limb actually stiffer in the flipped position? Why are you flipping it if it's how you want it?
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PatM, when I look at the bow the limb on the right seems slightly stiffer (not having the same arc as the limb on the left). Then I rotate the bow, now the limb that was to my left is now to my right seems to be the stiffer of the 2. This cannot be, if one limb is stiff (lets make it the bottom limb), then it should remain that way no matter which way I look at the bow.
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No, that is also dependent on how the bow is stressed when bent. The bow should not be mounted on the tiller like a crossbow.
Also you haven't said why you are flipping it is you're happy with it the first way.
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Loui, I had the same problem, drove me crazy and caused me to make a few kiddie bows.. I' only have about 5 successful bows to my credit so I'm no expert. Pat M is correct if youre looking at it strapped to a tiller tree it could stress one limb differently, it will drive you crazy. Use a mirror and grip the bow in different positions and the tiller will change slightly. Also check out Dons thread on Balance in tillering. Pictures will also mess with you're head as well.
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Never mind what it looks like. You should focus on how it feels when it is being drawn
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This is what she looks like. But on the tree she freaks me out.
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We shoot bows by hand, not off the tree.
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Nothing wrong with that tiller. Don't let the tree fool you. It's great for making sure things are even for getting to brace. The best thing to check tiller is to use your phone and take a photo of you drawing the bow. It allows you to really study the tiller.
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You need to forget the tree at this point and gauge the tiller purely by hand. Like these guys said. The tiller in the hand is what is important. The tree isn't always the same but it's not ultimately important.
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And, the sooner you get confident enough to not ask for opinions here, the better off you will be. ;)
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Looks good to me too,nice bend.
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Never mind what it looks like. You should focus on how it feels when it is being drawn
Mark, what do you mean by this?
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And, the sooner you get confident enough to not ask for opinions here, the better off you will be. ;)
This may be true, but the way you gain confidence is to ask questions- keep asking. I have been building bows for 20 years and I wstill ask about tiller.
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If your'e having trouble deciding on tiller, here are some options to help:
Ask someone else (you did!)
Use a measuring tool such as a tillering gizmo.
Take a photo and superimpose a circle or oval onto it.( look at photo while holding a CD up to it)
At brace height, look to see if the handle is parallel to the string.
Compare the angle between the string and limb tip.
Just cal it good as it is.
Looks pretty good to me. A little stiff towards the tips perhaps.
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It doesn't look like your bow has this issue, but sometimes a bit of propeller twist can cause that sort of optical illusion.
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Never mind what it looks like. You should focus on how it feels when it is being drawn
I hear this from a lot of the really experienced bowyers, but as I still feel like a newbie some days, I really am not sure what it means. What exactly am I trying to feel? I don't have a mirror big enough to look at my draw in, and getting someone to take a picture is difficult, especially when most of my scraping happens when others are in bed. Which leaves me with the tree. So what exactly is good tiller supposed to feel like?
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Never mind what it looks like. You should focus on how it feels when it is being drawn
I hear this from a lot of the really experienced bowyers, but as I still feel like a newbie some days, I really am not sure what it means. What exactly am I trying to feel? I don't have a mirror big enough to look at my draw in, and getting someone to take a picture is difficult, especially when most of my scraping happens when others are in bed. Which leaves me with the tree. So what exactly is good tiller supposed to feel like?
Maybe you should re-read this thread http://www.primitivearcher.com/smf/index.php/topic,62531.0.html
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Mark, I just read the "balance in tillering" thread again. With this in mind and your statement "never mind what it looks like", would you say that when you hand draw a bow, you are trying to feel if the handle is pulling more towards top or bottom? That is, you don't need to see it because you can feel that the limbs are unequal due to unequal pressure of the handle on the hand?
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Marc, I did read that thread, and it is part of why I raise my question. I can see the tilt in the picture, but how would you feel that in the hand? He may just as easily be aiming differently or holding the bow a little different. I assume that it is just because I have only made a dozen bows or so, and with more experience, maybe I will feel it better, but right now, I don't feel anything. What should I be feeling for? I can imagine some sense of balance, but you can't feel a stiff spot mid-limb, can you?
Don't get me wrong, your bows are gorgeous, so I know you know what you are talking about. I am just not sure where I should be focusing my attention.
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at first glance looked good to me,, about the never mind how it looks,, hmmm ,,, Im not sure that is exactly right,,
if the taper is even on the bow,, like a character stave,, the tiller may not look even,, althouh the limbs are working evenly,, then if the bow shoots great,, with perfect arrow flight,, then the look of it would be secondary to the way it performs,, but you are still looking at it,, if the bow is shooting great and maintaining a good unbraced profile,, then making it look different in the tiller if probably not gonna make it better,, (--)
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Mark, I just read the "balance in tillering" thread again. With this in mind and your statement "never mind what it looks like", would you say that when you hand draw a bow, you are trying to feel if the handle is pulling more towards top or bottom? That is, you don't need to see it because you can feel that the limbs are unequal due to unequal pressure of the handle on the hand?
Yes that is correct
Marc, I did read that thread, and it is part of why I raise my question. I can see the tilt in the picture, but how would you feel that in the hand? He may just as easily be aiming differently or holding the bow a little different. I assume that it is just because I have only made a dozen bows or so, and with more experience, maybe I will feel it better, but right now, I don't feel anything. What should I be feeling for? I can imagine some sense of balance, but you can't feel a stiff spot mid-limb, can you?
Don't get me wrong, your bows are gorgeous, so I know you know what you are talking about. I am just not sure where I should be focusing my attention.
You can feel a when a limb is stronger than the other but that won't tell you if a limb is tillered poorly. You won't be able to feel the bow tilting if you have a death grip on the handle.
at first glance looked good to me,, about the never mind how it looks,, hmmm ,,, Im not sure that is exactly right,,
if the taper is even on the bow,, like a character stave,, the tiller may not look even,, althouh the limbs are working evenly,, then if the bow shoots great,, with perfect arrow flight,, then the look of it would be secondary to the way it performs,, but you are still looking at it,, if the bow is shooting great and maintaining a good unbraced profile,, then making it look different in the tiller if probably not gonna make it better,, (--)
A backed bow is usually pretty uniform in the way it looks but there are always exceptions to every rule
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Thanks Marc, that is helpful.
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Thanks for asking, something I was wondering as well and was puzzled by this past weekend. Flipped it a few times and then figured it must just be in my head
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Thanks for all the feedback guys. You know, sometimes the mind can play tricks and completely shake your confidence. This is my second bow, but really my first real bow. I made one out of cheap pine just prior to this so I can get a feel for the tools I needed to use. Pine is a NO NO for bow wood, I do know that, but heck, it was purely a practice piece, which actually came in at 26# at 27" and I shot about 50 arrows with it too, until I saw a compression fracture on the belly. Pine bow is now a wall hanger. I was worried I would over tiller this hickory/ipe one until I had a kids bow. Finished tiller now, bow comes in at 38# at 28". My goal was 40# at 28", so I'm pleased with the result.
Now to finish the handle and shoot some arrows.
Some pics of the pine bow.
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You may find the actual tiller rig isn't set up true.
Just 1/8" out and it can cause the effect you are mentioning.
I have the bow resting on a curved block so that it can rock, some people prefer a square block which stops the bow slipping off.
Anyway, it's better (IMO) to support the bow where it will be getting hand pressure and draw the string from where the fingers will pull it. This set up is not symmetrical but it better represents how the bow will be used.
Have a lok at this post from my blog:-
https://bowyersdiary.blogspot.co.uk/2013/03/tillering-symmetry.html (https://bowyersdiary.blogspot.co.uk/2013/03/tillering-symmetry.html)
it may show what I mean better.
Del
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The length of your bow and the materials used make it a good candidate for piking to gain weight.
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Looks like its time to shoot some arrows...I like the slightly positive upper here...I think you may be over thinking this...How does it shoot...It is hard to detect a slight imbalance in hand especially a heavy bow...You look balanced from here...See how it feels loosing an arrow...You look low wrist, nothing wrong if this is your style...2nd bow A+...
Don
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Well, I've seen that also, Louie.
I use a rope and pulley and do not support the bow.
I tiller from the center.
Nothing approximates how it feels in the hand.
Is the bow tilting or is the handle pressure even? Those are questions I ask myself every time I take the bow down from the rope and pulley and test with short pulls.
I finish tiller with a digi pic taken by my wife or daughter.
Also, I use my patio window at night. Gives a nice reflection.
I like the tiller even or bottom limb slightly stiffer which you appear to have.
Looks good to me.
Jawge
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"Do you guys suffer from this optical illusion sometimes?"
Yup, all the time. Less so in laminated bows. Propeller twist can be caused by making the limb thicker down one side. This often happens to me just because of how my bow rests in the vise, where I have to stand, and how I hold my tools. Something to watch for in the future. Read the Sticky thread above about limb-tip lean and twist caused by this.
One thing that taught me about how to "feel" a bow in the hand is purposely pulling the string from way above and way below where you really WOULD to shoot an arrow, while leaving your bow hand in the right place. If your bow is balanced, pulling the string from too high will make the bottom limb feel week and the bow's upper limb will tip back toward you, and vice-versa.
Once you are familiar with the feel, try pulling an unfinished bow from the correct points on handle and limb. A weak upper limb will lean the bow away from you and vice-versa.
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It's a shooter! Fletched some feathers onto a few carbon arrows (it's all I have at this point). Let loose about 30 shots. Hitting consistently within a 6 inch circle at 13 meters. I'm new to this and it was my first time shooting so I don't know if that is any good, but it feels pretty sweet to me.
I like this Archery thing, ALOT!
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Congratulations! Jawge
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Awesome!
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It doesn't look like your bow has this issue, but sometimes a bit of propeller twist can cause that sort of optical illusion.
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This! Arvin