Big Country

WOW! I am pretty surprised to hear the responses to this one. I can only go off of my own results, but when I shoot fixed blade heads(thunderhead or muzzy 125gr.)in excess of 280fps, I must index the blades to the vanes, or my groups get much bigger.
I did notice that when I set my rig up to shoot in the 250-260fps range, it does not seem nearly as critical.

These are only my personal findings, I don`t for a minute doubt anyone elses.

NRA,UBP,BASS Member
New Stanton,PA

IMN23D

BobCo.. Both the aluminum and carbon have weak sides. That little trick with the skate board bearings really do the trick.

BobCo19-65

What trick is that?

IMN23D

Get 3 skateboard or roller skate ball bearings, or get some from a bearing shop, they cost about $2.00 ea. (get the bearings with the closest inside diamater of your arrow shaft). Soak them in acetone or some other degreaser to clean the oil and grease that are in some of the sealed bearings. The idea is to get them to spin real free. Then take and put one bearing on each end of your shaft and one in the middle. Lay your arrow across a corner of your kitchen (or workbench) countertop. The two end bearings need to be supported on the countertop with an open area underneath. Now, push down on the center bearing. The arrow will spin in the bearings to the weak side (weak side up). Then I fletch my arrows with my cock vane on the weak side (I shoot with a release and Bodoodle Pro-lite with cock vane down). I like to keep the weak side down. This applies to release shooters. Now, finger shooters are different. They want to have the weak side to the side. Since I don't shoot fingers I don't remember if you want the weak side outside or to the inside. I like to have the weak side down because of the pressure applied to the arrow by the eliminator button and the arrow rest. The nice thing about this test is you can do it while it is fletched and with field points on. You can get a true indication of your arrow spine with componets installed. I have yet had to index my notks (turn them to get them to group correctly). NOTE: some of the carbon arrows indicate 2 weak sides. Don't know why but one is a little weaker than the other. I just use the weakest. If you get this, just push on the center bearing a little lighter, and lighter until you feel a difference while spinning the arrow during the test. (you'll see what I mean when you do the test)

BobCo19-65

<BLOCKQUOTE id=quote<font size=1 face='Verdana, Arial, Helvetica' id=quote>quote:<hr height=1 noshade id=quote> Then take and put one bearing on each end of your shaft and one in the middle. <hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face='Verdana, Arial, Helvetica' size=2 id=quote>

You put the bearings on the shaft???? Or are they in the shaft? I'm really not following this.


<BLOCKQUOTE id=quote><font size=1 face='Verdana, Arial, Helvetica' id=quote>quote:<hr height=1 noshade id=quote> The nice thing about this test is you can do it while it is fletched and with field points on. <hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face='Verdana, Arial, Helvetica' size=2 id=quote>

<BLOCKQUOTE id=quote><font size=1 face='Verdana, Arial, Helvetica' id=quote>quote:<hr height=1 noshade id=quote>The two end bearings need to be supported on the countertop with an open area underneath. Now, push down on the center bearing. The arrow will spin in the bearings to the weak side (weak side up). <hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face='Verdana, Arial, Helvetica' size=2 id=quote>

I don't understand how this can happen.

How can the bearings land anywhere but where they started from by simply pushing down on the center bearing. Won't they end up in the middle (if they are inside the shaft) if both ends are supported but the middle isn't.


Does anyone else do this?

IMN23D

Bobco, I probably made it sound harder than it is. The bearings slip on the outside of the shaft. The two outside bearings have to be supported someway. I use the inside corner of my countertop. If you wanted to support the shaft by the two outboard bearings with your hands and have someone apply downward pressure with the middle bearings you could do it that way too. All you want to do is put a slight bend (flex) in the shaft. As it is flexing it will rotate in the bearings. |-------|--------|

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Kind of get the idea? Let me know if I can help.

BobCo19-65

Hmmmmm. That is very interesting. Do you test each arrow more then once? Do you usually get consistant results with the same shaft?

Stealth_Force

NOT to dispute this test...but wouldn't this show the direction that an arrow is bent vs. how strong or weak the spine there is?
This test would work on PERFECTLY straight arrows, but I would suspect that an arrow with even a SLIGHT bend would mar the results...Just guessing.

IMN23D

Wow...just saw what that little diagram looked like. Kind of stupid looking. That isn't how I had it before I sent it, it must have transfered that way. What I was trying to show was an arrow that looked like a &quot;smile&quot;.

BobCo...Yes, I test each arrow a number of times. It always gives the same consistant result for each shaft. During the test, I usually hold the center bearing down and spin the arrow inside the bearings. You can feel the weak spot also. Don't forget to mark your weak side with a pencil or something before you spin while holding the center bearing down, so you can confirm it shows the same weak side. Like I said before, if you are holding the arrow down and spin it, some carbons give a &quot;false&quot; weak side feel 180 deg. from the actual one. If that occures with yours....don't flex the arrow so much, you will feel the difference (the false reading will disappear and you can still feel the actual one).

Stealth...you are correct. If your arrow is bent it will not be an accurate test. Why would you want to shoot bent arrows? They would not group, and this is what you're after.

I shoot carbons about 99.9999999% of the time so I don't think about an arrow being bent.

BobCo19-65

Thank for all the info IMN23D. I am going to have to try this. Actually, I pretty much always use aluminuns. But just wondered about carbons. Thanks again.