spine tester

[Elktracker]

I just made one of jmacks spine testers and after spineing some shaft I realized that the hooks are 26" apart then I cut my shafts down to 24 and added a 160 grain point,my spine is too stiff. How can I figure this out to where it works right? should I mount the hooks at 24" and re spine? And if I do this will I still devide my thousands by 26? or 24? hope this isnt to confusing. thanks

[stringstretcher]

Elk.  When you spine you arrow at the 26" post spread, you are spineing the arrow at 28" for an AMO deflection.   The rule of thumb is to add 5lbs of spine for every inch you go out past 28" and substract 5lbs per inch for every inch under 28.  IE"  if you have an arrow that you spined at 60lbs on your 26" center post and cut that arrow to 24, you know have an 80 lbs spine arrow.  4inches at 5 lbs per inch is 20 lbs.  60 +20= 80.

Hope this helps

[Elktracker]

Yes it helps allot thanks