I designed an AMO spine tester so I can start making wood arrows and this is the second iteration to improve things a bit.  This tester is 2.0 pounds at 26 inches per AMO standard.



I have improved the scale to also read deflection as well as AMO spine.  This deflection is not the same as Easton, et. al., report because they measure spine using 1.94 pounds at 28 inches.



The second improvement is adding a ball bearing assembly to the pivot point for the pointer.  The first version used a bushing arrangement that was OK but had a bit of stiction.  I think the weight applied from above, directly atop the pivot arm is a bit better than hanging a weight from the shaft.



Tell me what you think.
Kevin

Looks Great

Looks good! Curious,how do ya zero your pointer for different diameter or, uhh, err, crooked arras?
I really like the weight on top too!

On the left arrow support is a thumbscrew adjustment that zeros for different shafts.

Ok, now start making them for sale, I will be first in line. I like it better than my store bought modle.

Danny

Good lord! That's the finest looking homemade spine tester I've ever seen. Great work!!!      

Well Kevin,  you have come along way "Grasshopper" Very fine.....  Sorry I missed you all this weekend.  the deflection is a great addition. I want one .......we'll talk at breakfast..........Mark

I love it.  I'll be second in line.  Just wondering, why don't wood arrow manufacturers, shaft sellers just go to the Easton deflection standard?  Since most of us these days are coming from carbons and aluminum back to woodies?

Wow!
Kevin, that's some nice work! And I love your attention to detail! This spine tester should fit into every living room without disturbing the view of the "better half" in your life. Clever planed and done!     :D
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Quoteposted by Cutty47:
why don't wood arrow manufacturers, shaft sellers just go to the Easton deflection standard?  Since most of us these days are coming from carbons and aluminum back to woodies?

"Easton Standard"  :confused:  ???????    

Not ALL are comming "back" from something!
IMO those who had/do turn back - should not ask the "ridgid ones" to adjust to their new point of view, but get themselfs back to the good old sights.
Ahh, I don't know if I got this accross now - somehow difficult for me to explain ...

Falk, I'm not sure about you, but if you take your accuracy seriously, you bareshaft...

Ever try bareshafting woodies?  Don't work so well...

Sooo, any whooo...

Matching aluminum deflection to the same deflection in wood saves you a whole bunch of money in the long run.

I love bows.  Bows cost money.  Hunting trips cost money.  Poorly spined arrows are firewood.

People get discouraged buying expensive firewood.

People stop buying woodies.  Woodie dealers go out of business.

The "rigid" ones can find woodies anymore.

Have to go to Easton deflection anyway...

I've never even seen a simple chart comparing common aluminum arrows with wood arrow poundage.

Besides, demystifying and standardizing the wooden arrow spine is going to do nothing but bring more people back to shooting wood.

Think about it...with the advent of glass laminations, R/D bows, and especially FF strings, some sort of change should have been made...

All of this add five pounds for a "modern recurve," add another five pounds for "FF string"...add five more pounds for hardwood shafts over cedar because they don't recover as quickly, add another five pounds if your bow is cut close to center...

...so, I need an #80 spine out of a #67 LB?  Or is it a #75 spine?  And what about poplar versus chundoo?  What about hickory versus Ash?  And are hexpine shafts hardwood?  And how does laminated birch behave compared to hexpine?

Can you tell I've been trying to make the transition?  Lol...

nice looking set-up  

You want a little cheese with yer wine!
I have no trouble bare shafting wooden arrows.
Nice spine tester Cupcake. Makes my homemade job look like it was made in the landfill.

nice work Kevin, i'm in line for one as well.

wha did you use to print that metered chart on a curved plane like that??

Some software I've not seen before?

I know I'm setting myself up as a complete computer fool..but it doesn't bother me because I am...so tell me, please..how you printed that way?

High quality craftsmanship. Do you have an idea what you spent in materials to build it?

Cutty, here's a simple spine chart for ya:  http://www.arrowsbykelly.com/Spine_Charts.html

That's a slick tester!

Thanks Jeremy, I refer to that chart quite a bit.

Apologies for the rant...just finished a dozen POC and after shooting them I think they're underspined.

Cutty, Now you have a new project.  Build you a bow to match your arrows.  Then you get another bow and you get to keep your arrows out of the fire.  

I would be willing to bet you could sell them if bowbuilding is not an option.  But you know that already.

Nice work! If you make them they will sell...

"I want one" looks briliant would you consider making any to sell and how much

I'll take one.