Spine Jig Help
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Spine Jig Help
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???
Re: Spine Jig Help
Not sure but i saw a website a little while back with some good information. I will try and get the link for you.
Cheers, Toby
- stringnstik
- Posts: 1106
- Joined: Tue Oct 21, 2008 12:09 pm
- Location: Cranbourne
Re: Spine Jig Help
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.
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.
"I am the arrow..the arrow is me...together as one...I fly to thee"
"the stick maybe crooked and the string hath no form,
then married by bowyer, transforms when first drawn"
"twang....thud"
"the stick maybe crooked and the string hath no form,
then married by bowyer, transforms when first drawn"
"twang....thud"
Re: Spine Jig Help
Thanks
- CraigMBeckett
- Posts: 38
- Joined: Mon Jun 22, 2009 10:55 am
- Location: Cooma, NSW
Re: Spine Jig Help
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.
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.
- Attachments
-
- Spine.xls
- (59.5 KiB) Downloaded 88 times
Re: Spine Jig Help
Hope this helps: http://www.jamesmhill.com/Spine_Tester.html
Re: Spine Jig Help
This one might also help.
http://paleoplanet69529.yuku.com/topic/24031
http://paleoplanet69529.yuku.com/topic/24031
Cheers, Toby
Re: Spine Jig Help
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.
I don't think I worded the question properly...But I was able to fix the spine jig myself through trail and error.