Spine chart

[DC]

I've given a few bows to kids at the range and they seem to want to use carbon arrows. Is there a chart that would convert AMO spine(pounds) to Easton spine(deflection). I just want ball park static spine. I've done a Google search and anything I've found seems to want to get into dynamic with a bunch of inputs. One site had a half dozen or more(I didn't scroll all the way down) charts and had the gall to call it "simple". I could do the arithmetic but in this day and age someone has usually done it and posted the results(I'm lazy)

[Urufu_Shinjiro]

^ What he said....

[aaron]

The short answer is to use .600 shafts for kids bows and most primitive bows. For kids bows to be well tuned, you would want even less spine, but a .700 or more shaft is hard to find.
The long answer, I believe, is that 26/inches deflection= amo spine in lbs.
So a .500 shaft is about 52. A .600 shaft is 43 lbs.

[aaron]

If Easton measures deflection at 28 inches, the numbers may be off a little, but still in the ballpark.

[aaron]

I know a guy who swears by gt trad 15/35 with a footing made from aluminum 2117 shafting. Full length with a weighted insert works good for my , I mean his, 40 lb wood bows. Very durable

[DC]

The short answer is to use .600 shafts for kids bows and most primitive bows. For kids bows to be well tuned, you would want even less spine, but a .700 or more shaft is hard to find.
The long answer, I believe, is that 26/inches deflection= amo spine in lbs.
So a .500 shaft is about 52. A .600 shaft is 43 lbs.

I don't think that's quite right. Easton measures their deflection at 28 with a 1.92 lb weight and AMO is 26 and 2 lb. So you first have to convert Easton deflection into AMO deflection and then divide it into 26. I have a couple of aluminum arrows that I checked and for example, an Easton 340 measures about 295 deflection on an AMO spine tester. That's about 85%. So a 500 would be 425 AMO deflection which is 61#. I'm halfway to the chart and doing the arithmetic I didn't want to do

[DC]

If Easton measures deflection at 28 inches, the numbers may be off a little, but still in the ballpark.

Sorry, you were posting while I was figurin'   Now that I've done one I just have to do another and make a graph. I think it should be linear.

[willie]

but it seems like the spine offerings are limited on account of most all modern applications are more center shot

might have to just start adding tip weight to the lightest (easiest found, reasonably priced) arrows.

[DC]

A couple of ladies at the range managed to find some 1000 carbons. They look like knitting needles with fletching.

[loon]

There was that other thread with a formula. Could try that. I think TSA has conversion charts or something as well.

[TSA]

go to oak creek archery- he makes awesome spine testers- we exclusively use his.
his testers have the different graphs on them.

http://www.oakcreekarchery.com/ocapages/oakcreek1_003.htm

go to this page and the buttons at the bottom will take you to all the info and tables etc!
 
cheers!

[DC]

Awesome! Thanks Wayne, that's what I was after

[TSA]

yer welcome

[loon]

Awesome! Thanks a lot! The PDFs there are very helpful!

[TSA]

thanks,
 would be awesome to take all the credit- but the real
cred goes to kevin from Oak creek archery- hes  a really smart guy!- builds some awesome spine testers!