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bfisher
03-04-2010, 10:32 AM
A while back I had a friend build me a spine tester, something I've never had. Today I finally got a chance to check some of my new Gold Tip Entradas and was taken aback with the results.

First off let me say that I couldn't check them at the usual 28" span because they are cut to 26". so the bearings were set to 24". Not accurate for getting the actual spine, but should be OK for checking spine consistency around the shaft, right?

All arrows were checked with the nock index pointing up to start, this being called 0 degrees. I then checked each arrow at 0, 90, 180, and 270 degrees, zeroing the dial indicator to compensate for any UN--straightness of the shafts.

The first arrow showed a total spine deviation of .005", not all that bad. It went downhill from there with one shaft showing .011", another at .013" and the other three showing .015". The one thing that surprised me is that when I installed the nocks I happened to get lucky and have five of the six set to the stiff side---luck. What did surprise me even more was the spread of the readings. The lowest number I had was .533" and the highest was .580". Quite a wide spread between arrows. Maybe it's no wonder these things don't group the best.

Just for comparison I threw one of my ACC 3-18 arrows into the thing and came up with a total deviation of .002". I guess it's no wonder these things always group and tune the best for me. I'm getting more educated as I get older.

Now for you guys that have ever done this what would you consider decent numbers here?

shawnkfl
03-04-2010, 02:38 PM
the quality of gold tip shafts went way downhill once they left the country. typical of everything else built outside