I posted these on PowWow in answer to a nock high problem a shooter was having.
To me it shows you can't use the rule of thumb for bow tiller. It really makes a difference in the type of grip on the bow and the way the shooter holds it. Because of the higher wrist grip on my bows I will me tillering them 1/8" negative tiller and see how they shoot. These high speed slow motion videos show some amazing stuff.
Ok here is the first video that shows the effect of putting pressure low on the bow grip. I intentionally pushed hard with the lower palm of my hand on this video. The bow is 63" nock to nock with equal distance between the top and bottom limb from the string. The nock height is 7/16" above the shelf. I also used and aluminum arrow because they flex more than carbons which helps show the effect. You can also see how much osculation there is in the limbs because the low grip pressure really messes with the limb timing.
I'll get the next video up as soon as it's ready
High speed low grip effect video (https://www.youtube.com/watch?v=PhPbGLYtktg)
Here's the second video. Same bow same settings I just pulled on the riser grip with my lower 2 fingers which took the pressure off the lower limb. The arrow still flexes some but doesn't kick up like it did in the first video. Also the bow limbs settle down quicker.
High speed high grip video (https://www.youtube.com/watch?v=BcqoFJVgW-o)
This is why I'm changing my tillering setup to match Bowjunkie and Roy from Pa's setups. As they said you see what the bow wants and do that. Thanks again you two for sharing your knowledge.
That's why, when crafting bows, tillering trees should be set up to replicate the shooter's holds as closely as possible... or why even bother?
I'm going to have to watch the video when I get home.
QuoteOriginally posted by Bowjunkie:
That's why, when crafting bows, tillering trees should be set up to replicate the shooter's holds as closely as possible... or why even bother?
LOL :)
why even bother? because it is still easier to accept the en vogue method of tillering to a predetermined tiller measurement, even if it is completely wrong, than to actually observe what the wood is doing, assess what needs to be done and make it so. at the heart of tillering is a critical eye and making judgements that demand understanding.
happy to see a rising tide of wooden bowyers accepting the realities of tillering wooden bows and letting go of the misguided 1/4" positive tiller standard.
Jamie that goes for glass bow builders as well!
Your welcome, Ben. Cool video too, I'll bet the bow was a lot quieter in the second video too. And it's plain to see the flight of the arrow is much straighter in the second video. Tillering wood bows for equal limb timing makes them so smooth shooting and so very quiet at the shot. I've had so many complements on how quiet my bows are when shooting at a 3-D shoot. And there aren't even string silencers on them.
I can believe they shoot great as well Roy. Hey you're a pretty nice guy too but I won't tell anyone :thumbsup: