Hey guys,
I'm not sure if this is the correct place for this question. Anyway, do any of you know of a web site that shows how to build a tester and also explain how it works?
Thanks,
Z
Michael,
I'm doing the same thing right now. I'm not sure if I can post links but if you type these words into your browser: measuring arrow spine deflection, then in advanced search, under "None of these words" type in the word: Charts
You'll see a bunch of ways to make your own.
Ron
Sorry man I posted too soon.. Just search "Homemade arrow spine tester"... I found several different tutorials for making various designs. Try using the search feature here on TG too.
Ron
Ron,
I am still trying to understand this spine stuff. From what I understand, the devise uses a 2 pound wt. to deflect the arrow. The distance of deflection with a two pound wt. is what your spine is. I understand the deflection in inches, but I don't understand what the numbers are that it is converted to represent.
Thanks,
Mike
Mike, the shaft will be suspended between points 26" apart. When the 2lb weight is hung on the shafts the needle will point to a number on the scale (deflection in .001 of an inch). Lets say a shaft measures .335" deflection, you divide the 26" spread by .335 and it will give you 77.6, that shaft has a AMO spine of 77.6lbs. That is how wood shafts are measured, Aluminum and Carbon are measured between 28" points with a 1.94lb weight.(that is the ASTM measurement)
Eric
Search here for a spine gauge or spine tester. there's several. seach the net & find dozens. Stone simple in theory! I built mine with info here & some ideas from some other sites then use my own idea for suporting the 2# weight.
Ron, Eric,
I appriciate your explanation on a subject that only a newbie could ask.
All of you guys that answer these questions are so valuable to us less educated to this sport.
Thanks so much for you help.
Mike
Sure Mike, good luck with your project. If your building wood arrows, a spine tester is essential IMO, carbon and Alum are pretty consitent.
Eric