PDA

View Full Version : Had to adjust arrow rest to the right (Onza 3)



Phantonza
01-15-2013, 06:55 AM
Compared to my initial Onza 3 tuning almost a year ago (shooting "bullet holes" to paper and broadheads hitting the same spot with field tips), the biggest drift has been with the need to move my arrow rest more to the right to maintain proper tuning (the bow is RH model). The change was more than 1/10" compared to the initial tuning. The nocking point needed almost no adjustment.

Actually there is not much extra vane clearance left anymore with the riser after this adjustment, the rest is so close to the riser now. I would have rather kept the arrow rest where it was...

I wonder what actually causes this. The cables (and most probably, also the string) have stretched a bit, but does it have an effect to this? I could imagine that as stretching of the cables decreases some tension, also the sideways component of the force (due to the cable guard) decreases. And this would then cause the need to adjust the arrow rest sideways, as the "side balance" of the bow becomes different. But I wouldn't have expected such a relatively large need of sideways adjustment. If this theory was correct, I could of course add some twists to the cables and string and get the situation back to where it was.

Last spring, I changed the cable slide to a model that lets the cables stay closer to the center, since I could get enough vane clearance even so. I remember that I had to move my sight pins a bit to the right after that. I don't remember if I also had to re-tune the arrow rest, though. I think I will test this tomorrow with another cable slide that takes the cables more to the side. I would expect the tuning to change.

I don't recall having noticed a similar tuning issue with my old bow (Martin Phantom II, not a parallel limb bow).

TEN RING
01-15-2013, 07:15 AM
The first thing I would do is check your spec's ata, brace hgt. poundage and go from there

Phantonza
01-15-2013, 07:34 AM
The first thing I would do is check your spec's ata, brace hgt. poundage and go from there

Could do that, but I would like to understand what really causes the difference with the arrow rest and if my reasoning above was any good.

Brace height is unchanged (with my measurement accuracy, anyway), ATA is a bit longer (1/4...1/2" if I remember correctly), indicating some stretch. Pounds I didn't measure yet.

droppixel
01-15-2013, 08:43 AM
Did you change arrows or anything like that? Did you sight window get bumped one way or another?

Phantonza
01-15-2013, 09:50 AM
Did you change arrows or anything like that?


No.



Did you sight window get bumped one way or another?

Not sure if I understood the question...

wscywabbit
01-15-2013, 10:02 AM
One thing to consider is that as your strings stretch, your poundage will go down a little, making the arrows you use seem a little "stiffer" than they were before. This could, I suppose, (depending on the amount of stretch/loss) change your center slightly...

droppixel
01-15-2013, 10:56 AM
Did your sight get moved in either direction, could it have shifted from where you had it set. Bringing your pins out of alignment with your original center shot setup could have an effect on it ...

Phantonza
01-15-2013, 11:50 AM
Did your sight get moved in either direction, could it have shifted from where you had it set.


That wouldn't make a difference anyway, since sight movement doesn't affect paper test or boradhead tuning. It was the arrow rest I had to adjust - and of course, also my sight after that.

Lab Rat
01-15-2013, 11:55 AM
Could your draw length change enough to mess up form? I have read that the left tear for right hand shooter is common if draw length is too long. Also could you be getting any rest or facial contact? I tried using FOBs but my stupid face would cause them to kick the arrow a little. Also have you tried a bare shaft?

Phantonza
01-15-2013, 11:57 AM
One thing to consider is that as your strings stretch, your poundage will go down a little, making the arrows you use seem a little "stiffer" than they were before. This could, I suppose, (depending on the amount of stretch/loss) change your center slightly...

Good point, but I don't believe that theory. I have never noticed that a "too stiff" arrow would make any difference with compound bow (it's a different thing with traditional bow, of course, since it does not tolerate too stiff arrows because of archer's paradox).

I have sometimes tested this: when the bow has been tuned properly with paper test, it shoots perfect "bullet holes" also with a stiffer arrow.

In contrast, too weak arrow would be a problem.

Anyway, I'm sure the difference in pounds is quite minimal. I could also easily test it by screwing the rest two full turns to my limb bolts.

Phantonza
01-15-2013, 12:02 PM
Thanks for replies everyone! :)


Could your draw length change enough to mess up form?


It is indeed 1/4" longer now than initially. Feels very good still and my bow arm is not overly straight. Don't think so.



Also could you be getting any rest or facial contact?


If there was some fault in my Ultra Rest HD, then maybe. Didn't test this with powder or anything, but since I could get the bow back in tune with arrow rest adjustment, so I don't think this is the case.



Also have you tried a bare shaft?

No. Paper and broadhead tuning. I use paper test to bring tuning close, then finalize it with broadhead tuning.

So basically there is no big problem - the arrows fly great now, I just wonder what caused the need to adjust the arrow rest more to the right. One thing though: I use No-peep, and since I also had to adjust my sight pins more to the right, the No-peep blocks the sight picture more than before - it also almost blocks the bubble level of the sight. That's one reason why I preferred my initial tuning. Although this could be fixed by moving the No-peep to an upper position on its mounting bracket.

Phantonza
01-16-2013, 01:11 AM
I wonder what actually causes this. The cables (and most probably, also the string) have stretched a bit, but does it have an effect to this? I could imagine that as stretching of the cables decreases some tension, also the sideways component of the force (due to the cable guard) decreases. And this would then cause the need to adjust the arrow rest sideways, as the "side balance" of the bow becomes different.


After some more thinking, I'd say this cannot be the reason. Considering the force sideways, the decreased tension of the cables due stretching would pretty much equal just backing the limb bolts out. And I have never seen that having an effect to arrow rest adjustment.

Next theory: perhaps the limbs have twisted slightly over time...? Need to check cam lean. When I first got the bow, there was none.

Phantonza
01-16-2013, 01:32 PM
It's the cable slide!

I have been experimenting with different models to find one with minimal friction, to ensure reliable operation of my QAD Ultrarest HD arrow rest (that's another long story). Different models vary with how far to the side they pull the cables. I checked today and I could see the difference in paper test between two models. And with broadhead test, I even noticed a clear vertical effect, which was a little surprising.

Don't take changing your cable slide lightly - you may need to retune your bow :p

Arrow Splitter
01-16-2013, 01:47 PM
That's interesting, I will have to keep that in mind. Congrats on solving your own mystery.;):cool:

A.S

Lab Rat
01-16-2013, 03:14 PM
You should experiment with the bent cable slide rod or a tilt tamer. They will radically change the center shot of the bow. It is amazing how much you can feel in the riser. I could feel the torque in the riser in my bow hand. When I unhook the cable slide it immediately releases the side torque and you can feel it in your bow hand. This was with the Z. My Onza is stiffer though with the bridged riser.

Phantonza
01-17-2013, 04:44 AM
You should experiment with the bent cable slide rod or a tilt tamer. They will radically change the center shot of the bow. It is amazing how much you can feel in the riser. I could feel the torque in the riser in my bow hand. When I unhook the cable slide it immediately releases the side torque and you can feel it in your bow hand. This was with the Z. My Onza is stiffer though with the bridged riser.

One reason why I wanted to experiment with different cable slides was minimizing torque. The original cable slide had excessive vane clearance, therefore it induces torque in vain - not that I would have noticed any problem with it, though.

I was considering tilt tamer / bent rod at some point, but wasn't convinced that they would actually increase accuracy. So I didn't purchase one for testing it.