bare shaft tuning question
09-13-2002, 07:47 AM
#1
Thread Starter
Join Date: Feb 2003
Location: Fort Wayne in USA
Posts: 71
bare shaft tuning question
I did a little bare shaft tuning last night. At 25 yds my bare shafts grouped 5 inches low and an inch to the right. Is this good or bad? I could see the arrow kick to the right as it flew to the target. Does this mean I need to move my rest?
09-13-2002, 08:54 AM
#2
Join Date: Feb 2003
Location:
Posts: 348
RE: bare shaft tuning question
I'd say that since the arrows are grouping, you've found an acceptable shaft size for your bow. If the shafts were not correct, you'd most likely have gotten arrows flying all over the place. At this point, you should be able to perform some paper tests to fix the impact point and kick to the right.
For the low impact, you can adjust the vertical alignment of your nocking point. For the kick to the right, you would adjust the horizontal of the rest. The draw weight of the bow can used to make fine adjustments to the fishtailing as well.
-Mike
For the low impact, you can adjust the vertical alignment of your nocking point. For the kick to the right, you would adjust the horizontal of the rest. The draw weight of the bow can used to make fine adjustments to the fishtailing as well.
-Mike
09-13-2002, 09:41 AM
#3
Join Date: Feb 2003
Location: Florence AL USA
Posts: 53
RE: bare shaft tuning question
That is great! Congratulations. With results that good, you know for a fact that your arrow spine and bow are well matched, and your centershot setup is pretty darn good.
Unless you have a very easily adjustable, very well calibrated centershot adjustment, I wouldn't touch the rest. One inch at 25 yards is a minute amount. (By the way, I'm assuming you're shooting a rope loop or release.) If you're shooting fingers, a very slight draw weight adjustment might correct for spine.
If you do have the caliper release or loop, the vertical difference (5"
, could be attributed to nocking point or spine. To make small nocking point adjustments, try turning only one limb bolt. This rotates tiller ever so slightly and moves the rest in relation to the nocking point on the string. Tightening the top bolt has the same effect as loosening the lower bolt, and the "rule of thumb" to remember is tighten in the direction you want the nocking point to move. In other words, to raise the nocking point up, tighten only the upper limb bolt. For instance, on your setup, I'd only tighten the top a 1/16 to 1/8 turn (about the angle between one hour and the next on a clock face). This is an easy way to make VERY FINE adjustments to the nocking point.
Unless you have a very easily adjustable, very well calibrated centershot adjustment, I wouldn't touch the rest. One inch at 25 yards is a minute amount. (By the way, I'm assuming you're shooting a rope loop or release.) If you're shooting fingers, a very slight draw weight adjustment might correct for spine.
If you do have the caliper release or loop, the vertical difference (5"
, could be attributed to nocking point or spine. To make small nocking point adjustments, try turning only one limb bolt. This rotates tiller ever so slightly and moves the rest in relation to the nocking point on the string. Tightening the top bolt has the same effect as loosening the lower bolt, and the "rule of thumb" to remember is tighten in the direction you want the nocking point to move. In other words, to raise the nocking point up, tighten only the upper limb bolt. For instance, on your setup, I'd only tighten the top a 1/16 to 1/8 turn (about the angle between one hour and the next on a clock face). This is an easy way to make VERY FINE adjustments to the nocking point.
09-13-2002, 10:26 AM
#4
Thread Starter
Join Date: Feb 2003
Location: Fort Wayne in USA
Posts: 71
RE: bare shaft tuning question
Capstone
Are you sure I should turn my limb bolts? My tillers are currently even. I am shooting a Mongoose release on a string loop. My arrows are Gold Tip XT 7595 tipped with 100gr pts. My draw wt is 70#.
Are you sure I should turn my limb bolts? My tillers are currently even. I am shooting a Mongoose release on a string loop. My arrows are Gold Tip XT 7595 tipped with 100gr pts. My draw wt is 70#.
09-13-2002, 11:55 AM
#5
Join Date: Feb 2003
Location: Florence AL USA
Posts: 53
RE: bare shaft tuning question
Barile,
Tiller doesn't have to be dead even. It really doesn't have to be even close, but that's another discussion. My point is, you're not going to mess up some "mystical" tune by turning one bolt and not the other. Just as I said, turning one bolt (and, remember, I'm talking about a FRACTION of a turn) will simply rotate the riser (a minute amount) and have the same effect on nocking point as raising/lowering the rest or physically moving the loop would have. Using the limb bolt is just an EASIER way to do it, because you have such "fine tune" control. Also, as close as you are to being perfect, you don't need any more than a fine adjustment.
Tiller controls the angle that the riser sets in your hand. You won't throw the entire bow "out of whack" if you move one bolt and not the other. Let's say a bow is "tuned" at even tiller. If you tighten the upper bolt a large amount and it "throws it out of tune", you haven't disrupted how the bow operates, you've just 1) raised the nocking point and 2) changed the appearance angle of the arrow compared to the shelf.
2) has no effect on tune; it's just a matter of appearance. 2) also changes how the bow "sits" in your hand at full draw. Some people adjust this setting to where they feel most comfortable.
1) does have an effect on tune. The nocking point just moved up the string. The bow is now "out of tune" because the nock height changed, NOT because the tiller changed. The bow can be returned to the original "tune" by adjusting the rest or moving the nock point to remove the amount that the nock point moved up due to the tiller adjustment.
Now, I said all that to prove the point that you're not going to do any damage by turning your upper bolt 1/16 turn. You are not going to have to go through all that I mentioned above, because you're not going to turn the bolt that much. You just shouldn't be wary of moving away from even tiller. (No more than you'd be wary of moving your loop down the string a FEW THOUSANDTHS OF AN INCH, because that's how small a change we're talking about.) In other words, don't sweat it.
By the way, with the bare shafts hitting low, and your arrows seeming to be adequatelty stiff, I'd say your problem (if you want to call it that) is the nocking point is slightly HIGH. The adjustment I suggest you make is a TWEAK tighter on the lower limb (or a TWEAK looser on the upper).
Tiller doesn't have to be dead even. It really doesn't have to be even close, but that's another discussion. My point is, you're not going to mess up some "mystical" tune by turning one bolt and not the other. Just as I said, turning one bolt (and, remember, I'm talking about a FRACTION of a turn) will simply rotate the riser (a minute amount) and have the same effect on nocking point as raising/lowering the rest or physically moving the loop would have. Using the limb bolt is just an EASIER way to do it, because you have such "fine tune" control. Also, as close as you are to being perfect, you don't need any more than a fine adjustment.
Tiller controls the angle that the riser sets in your hand. You won't throw the entire bow "out of whack" if you move one bolt and not the other. Let's say a bow is "tuned" at even tiller. If you tighten the upper bolt a large amount and it "throws it out of tune", you haven't disrupted how the bow operates, you've just 1) raised the nocking point and 2) changed the appearance angle of the arrow compared to the shelf.
2) has no effect on tune; it's just a matter of appearance. 2) also changes how the bow "sits" in your hand at full draw. Some people adjust this setting to where they feel most comfortable.
1) does have an effect on tune. The nocking point just moved up the string. The bow is now "out of tune" because the nock height changed, NOT because the tiller changed. The bow can be returned to the original "tune" by adjusting the rest or moving the nock point to remove the amount that the nock point moved up due to the tiller adjustment.
Now, I said all that to prove the point that you're not going to do any damage by turning your upper bolt 1/16 turn. You are not going to have to go through all that I mentioned above, because you're not going to turn the bolt that much. You just shouldn't be wary of moving away from even tiller. (No more than you'd be wary of moving your loop down the string a FEW THOUSANDTHS OF AN INCH, because that's how small a change we're talking about.) In other words, don't sweat it.
By the way, with the bare shafts hitting low, and your arrows seeming to be adequatelty stiff, I'd say your problem (if you want to call it that) is the nocking point is slightly HIGH. The adjustment I suggest you make is a TWEAK tighter on the lower limb (or a TWEAK looser on the upper).
