Spine Jig Help

[M.Hogan]

I am wanting to make a spine jig and was wondering after I make it how do I know what spine a particular arrow is...Do I have to place an arrow I already know what the spine is and mark where the needle is on the wood...then when I test the spine of the arrows I will know???

[pdccr]

Not sure but i saw a website a little while back with some good information. I will try and get the link for you.

[stringnstik]

sorry mate i expected a dozen slightly better experienced folk would have answered this for you by now. Search for some of my posts I had a crack at a few different ones and there will be some links to them in those posts.
Most have a dial which if you stick to the design right will read out either inch deflection or even give you spine indication directly. Some are a little crude, depends how accurate you want it all to be.

[M.Hogan]

Thanks

[CraigMBeckett]

Hi M.Hogan,

If you use the AMO (American Archery Manufacturers Organisation) method the spine of a shaft is measured using a span of 26 inches subject to a 2 pound point load applied at the centre (why does this forum's spell checker use US spellings?) of span is defined as span/deflection or 26/deflection. Thus a 26 lb spine arrow will have a measured deflection of 1 inch. Although the AMO system uses a 26 inch span for measurement its results are intended for 28 inch arrows.

The British GNAS has/had a different system, where I believe the actual lenght of shaft being measured was used and a 1.5 pound weight applied.

Attached is an excel workbook with spreadsheets and charts for both AMO and GNAS spine.

Craig.

[BMB-Mal]

Hope this helps: http://www.jamesmhill.com/Spine_Tester.html

[pdccr]

This one might also help.

http://paleoplanet69529.yuku.com/topic/24031

[M.Hogan]

Thanks for the help everyone.
I don't think I worded the question properly...But I was able to fix the spine jig myself through trail and error.