I know alot of people who float their arrows in a tub to find the spine. They cork the ends then mark the high side.

Does it work? Beats me! I think tru-flite does something along those lines. I am not sure about that, but I do know that many top archers order their arrows from tru-flite, so however they build them must work pretty good!

NRA,UBP,BASS Member
New Stanton,PA