# Blade rest tuning



## WhitBri (Jan 30, 2007)

2712 250 point. Got them to paper tune. But when powder testing arrow I'm getting a single line down entire shaft. Should I just put the line between fletch and call it good or what should I try to get it to lift up and give 100% clearance


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## bigHUN (Feb 5, 2006)

Did you ever hear those "paper is good for wiping" and the other one is that "powder is good for...especially the Johnson baby powder...."
joke aside
what distance did you shoot the paper? what is your skill level meaning in front of the paper?
what blade thickness, length, what angle, what is a height relation to the nocking point? and then
what is your shooting skill level, and the most important "how far you want to get with this"? 
Now, my story....I am shooting for competition FITA and Field, my blade is set in same way as your that the arrow (those tiny CX nano pro's) kissing looong way the blade and still clearing the helical vanes. I set the blade stiff (stiffening support below and above the blade) so when the arrow leaves the tip is not bouncing back and hitting the nock...I believe I don't have 1 mm = 0.040" height difference between nocking point and the blade resting point.
I have a good read for you here http://www.archerytalk.com/vb/showthread.php?t=2198003


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## WhitBri (Jan 30, 2007)

Paper from 3' to 6 yards. Paper skill level I can produce consistent reliable results. Aae pro blade rest .012 blade 35 degree approx. tried .010 but appeared to be bending a little at full draw. Nock height 1-16" above. I'm a 55 to 58x shooter and want to get to 60x and better.


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## WhitBri (Jan 30, 2007)

bigHUN said:


> Did you ever hear those "paper is good for wiping" and the other one is that "powder is good for...especially the Johnson baby powder...."
> joke aside
> what distance did you shoot the paper? what is your skill level meaning in front of the paper?
> what blade thickness, length, what angle, what is a height relation to the nocking point? and then
> ...


Responded above


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## N7709K (Dec 17, 2008)

Line favoring left or right side?


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## bigHUN (Feb 5, 2006)

WhitBri said:


> Responded above


You are all set


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## WhitBri (Jan 30, 2007)

N7709K said:


> Line favoring left or right side?


Left prong on left side of arrow looking from behind.


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## bigHUN (Feb 5, 2006)

I would not worry about that line if you happy with reading a paper tear at 5 meters, but 
Take a magnifying glass and inspect your blade tip. Did you got one side-tip wearing more then the other side-tip (two tips of the "V")?
I believe one tip is worned out more that the other...do to a reason what is very common....
I would call it just perfect if the arrow leaves the launcher starting nose diving, but considering it unnecessary if the point is pointing towards the riser. (or towards the right in your case).


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## ron w (Jan 5, 2013)

tuning a launcher blade with big diameter shafts and heavy tips for softening the spine , will always be a compromise at the rest. because of the heavy points on an overlt stiff shaft, the shaft will flex in other than perfect directions. this doesn't matter at all, as long as the groups at the other end of it's fight are good. the whole concept of using heavy tips on large shafts for line cutting, is "outside the box, of normal tuning "rules", so why would a contact mark that does appear to be normal, or follow the "rules" be of any concern ?.


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## WhitBri (Jan 30, 2007)

ron w said:


> tuning a launcher blade with big diameter shafts and heavy tips for softening the spine , will always be a compromise at the rest. because of the heavy points on an overlt stiff shaft, the shaft will flex in other than perfect directions. this doesn't matter at all, as long as the groups at the other end of it's fight are good. the whole concept of using heavy tips on large shafts for line cutting, is "outside the box, of normal tuning "rules", so why would a contact mark that does appear to be normal, or follow the "rules" be of any concern ?.


My archery experience is usually out of the norm. 32.25" dl which means longer arrows in most cases. Heavier spines, etc. Bought the 2712s and 250 points. Had to cut them to 31" to get them to spine stiff enough.


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## bigHUN (Feb 5, 2006)

*this is a 100% spine tune*









and will wear the launcher blade L-R tips evenly.
because I set the "equipment" well balanced, my arrow at the moment of launching it won't flex in horizontal plane at all,
only flex would be vertical (this what I planned to do) and will start nose dive (note the spine check/fletching in combination of the nocking point).
Your arrow is flexing both in horisontal and vertical plane, maybe a combination of two creates some spherical run out first couple yards before stabilizes.
If that line you mentioned is really bothering you, do a french tune as much possible (if the overly stiff shaft is still within range), or adjust/tune the bow and arrows together.
Or, just keep shooting, because none of these advises will give you an extra "x" anyways, answer to that is somewhere else in the mental section.


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## ron w (Jan 5, 2013)

eliminating, or minimizing shaft flex in the horizontal plane, is why the shoot through idea was developed. it is also the easiest set up to tune well, for this same reason.
any conventional system with the side torque of an offset cable guide will induce flex in both the vertical and the horizontal planes, no matter how well the rest, string and pin line up. all that says is that the bow is tuned and arrows spined , as well as can be, and that the shooter's form has as little torque input as can be had on the shot. mechanically, the bow still imparts a sideways torque to the rigs line of travel itself, that will make the shaft flex in the horizontal plane.
if this thread was about someone's shoot though bow, your post would be valid, however, if this thread is pertinent to a conventional, offset cable rod bow, your post compares apples to oranges.


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## jmann28 (Nov 22, 2010)

N7709K said:


> Line favoring left or right side?


Interesting question, can you explain why you ask that question? I'd be curious on this topic as well, I never seemed to be able to get rid of a single line down the entire shaft, which then had the other prong that wasn't making any contact on the arrow hit the fletching on the way by.


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## Tiroarco (Nov 6, 2012)

If you have a single line it indicates you have more pressure on that specific prong (v of the tongue lizard). All this means is your centre shot is not perfect (close, but not perfect).
If it favours the left side....I would move the rest to the left. Very small increments (my DS Advantage is 0.002" per click) until you start forming two consistent lines (Which means even pressure or "perfect centre shot" or perfect travel). In my experience we are talking 2 to 4 thousandth's of an inch with my bows. My bows are really easy to find centre shot (set it in the middle of the riser tunnel) and fine tune from there. This may not be the case for other bows......



jmann28 said:


> Interesting question, can you explain why you ask that question? I'd be curious on this topic as well, I never seemed to be able to get rid of a single line down the entire shaft, which then had the other prong that wasn't making any contact on the arrow hit the fletching on the way by.


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## jmann28 (Nov 22, 2010)

mgnasi said:


> If you have a single line it indicates you have more pressure on that specific prong (v of the tongue lizard). All this means is your centre shot is not perfect (close, but not perfect).
> If it favours the left side....I would move the rest to the left. Very small increments (my DS Advantage is 0.002" per click) until you start forming two consistent lines (Which means even pressure or "perfect centre shot" or perfect travel). In my experience we are talking 2 to 4 thousandth's of an inch with my bows. My bows are really easy to find centre shot (set it in the middle of the riser tunnel) and fine tune from there. This may not be the case for other bows......


This setup bareshafted at 25 yards, not sure how much better then centershot could have been


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## bigHUN (Feb 5, 2006)

ron w said:


> ... if this thread was about someone's shoot though bow, your post would be valid, however, if this thread is pertinent to a conventional, offset cable rod bow, your post compares apples to oranges...


I almost sad BS but on the other hand it was long ago I had a cable guarded bow, something could get changed, but still I am playing with blades and materials for a very long time , you may be partially right. Lets talk about these details.
When the arrow sits on the rest, its sits there only, right? You can apply torque to the riser as much you like....
At the moment when the nocking point start moving (but the tip point is still static) the shaft start bending in direction of "less resistance" - now, I am not going to discuss what we learned there in this thread, and we can be prepared for that bending direction, a vertical plane is enough and no need one more - a horizontal plane to bend as well. The bending amount is determined by the "spine stiffness" how we call it public wide...and this amount could be compensated but that is an other story...
At the moment when the tip point start moving we already have a a big bend in the shaft, also a direction where it is pointing, right?
.....still no effects from torque....because...assuming we did some tuning for the cam lean....also creep tuning...
so the point tip start moving, following that direction....big bend in the shaft length do to nocking point is already in motion... 
(did we set the resting point higher or lower, that will be the length amount of contact between the launcher blade and the arrow shaft....)
so, started moving out, the launcher blade is doing a looong kiss on the shaft....still in contact.....
Now I would take a brake here, you can help me out from here telling us "when" is that moment that the torque from riser and cables start kicking in through cams and running down on the string? Yes, it will happen, but when? Will the carbon still be in the contact with the blade? Maybe yes maybe no.....


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## montigre (Oct 13, 2008)

n interesting study....https://www.youtube.com/watch?v=ikGpIqlO5VQ


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## ron w (Jan 5, 2013)

the shaft can't bend until it receives some resistance to being pushed at one end. that resistance is obviously the weight of the tip and some from the shaft itself. until that resistance is realized the shaft stays straight except for what little sag there is between nock and rest. the shaft does not flex until it starts moving forward, because it is the forward movement that generates the resistance, that makes it flex......no generation of the resistance,...no flex..


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## ron w (Jan 5, 2013)

sideways torque, is applied as the bow is drawn, by the cables being loaded under draw tension. because this load is offset from the string, the load torques the bow sideways at full draw. it is actually the release of this lad that applies the sideways influence on string alignment and nock horizontal nock travel, as the side ways torque from the offset guard is reduced as the bow goes from full draw to brace. it's actually the instantaneous nature of this release that causes the sideways influence. if it happened at a slower speed, such as in drawing, it would not be so influential.....do you feel the bow torqueing in you hand as you draw ?.....maybe sometimes, just a little bit, but not much. if you could draw, as fast as the bow works when shot, you feel it allot.
now, the elimination of that cable guard, on a shoot through rig, eliminates this sideways torque almost completely. the only amount comes from the amount of offset, between cable groove and string groove on the cams, in bias with the center of the bow. as bows became more truly "center shot", shoot through rigging became more sensible.


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## bigHUN (Feb 5, 2006)

ron you are correct elaborating where the torque is coming and what it does, I have no other comment to you, only that 
the line on the left side of the shaft; also the worn blade tip on the left side; also having the scope pin not aligned with the rest (or isn't the rest in the center between cams); these have nothing to do with a cable guarded bow or else.
These are absolutely related to spine stiffness, do we have it within a tuneable range or not. How much is this important for indoor 20 yard shooting is totally different story (outdoor long range would definitely suffer), correcting it will give us an extra "x" is again a big question.


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