I just got an Ace 203 spine tester with a 1 lb weight, I am aware that it’s designed for woodies, if I want to use it for carbons, with the same 1 lb weight , can I convert the reading? Is the correct conversion this , Measured spine divided by .825 = carbon spine.

What exactly are you trying to solve for?

When I put a “500” on my wood spine tester, it will read #65…. But because of standards, the deflection is NOT .500 — more like 400.

Good news is that you really don’t need a tester for Carbon; they’re pretty reliably “as marked”.

What exactly are you trying to solve for?

When I put a “500” on my wood spine tester, it will read #65…. But because of standards, the deflection is NOT .500 — more like 400.

Good news is that you really don’t need a tester for Carbon; they’re pretty reliably “as marked”.

There is a way to convert. Try Oakcreekarchery website. If Kevin sees this post he may answer as well. He has all that math stuff worked out

M60gunner, I’ll check oakcreekarchery, Thank You!

M60gunner, you were right, found it on oakcreekarchery website, my guess was pretty close. It was 0.825419

Good, figured he had it . I still remember way back when we tested carbon arrows on his spine tester. We were amazed at the varying amount between shafts let alone manufacturer. Then we discovered they had a high side like woods. We were still of the aluminum arrow era were tolerances were tight even on cheap shafts.

That’s interesting… Unless I’m looking at something like GT Trad blems, I really don’t see that much variability with carbons…

Also, consistency seems better with 500-600 than 340-400 ranges. Maybe the woodgrain layer (and just more layers in general) make it just harder to nail the consistency?

Where I'm confused is the 1 lb weight.

I've never been aware of a 1 lb weight.

Only know of 2 lb for AMO, and 1.94 lb for ASTM.

Someone enlighten / catch me up.

Rick

Yeah, the one pound weight had me confused

https://acearcherytackle.com/ace-spine-master/

It’s wall-mounted; saves space. Different geometry so that you get the same answer with half the usual weight.

And for 25 bucks, you can buy a weight that corrects the calibration to the carbon/aluminum standard.

I’m not sure that I see any value in testing aluminum— haven’t had any unmarked shafts and as long as they’re straight, they will spine out to spec (can’t imagine otherwise).

And for carbons, as I mentioned above, they’re not EXACTLY consistent, but probably closer than wood of comparable cost and much closer than 99% of us can shoot.

M60gunner , you’re absolutely correct about variation in spine in carbons, they’re definitely not as marked when you start spine testing them. They’re all over the place. I have a digital spine tester that I use for carbons , but now that I got the ace I find it much faster to set up and check spines. Plus I like to see the needle move on the beam scale , it’s more intuitive. Overall I see that aluminum arrows are still more consistent than anything else, they’re straighter, and have less spine variation.

Rick Barbee , grizz, … yes it’s a 1 lb weight, I didn’t believe it myself but checked on scale and it’s exactly 1 lb. The one ace sells for carbons is 1.1875. I figured why buy another weight if it’s just as easy to convert by calculating. I’m just too cheap, lol.

You guys just HAD to do that, didn’t ya? Now I’m gonna end up checking a barrel full of shafts to see how much variance I get….

I would get a 2# weight from ACE. The 1# weight is for kids light weight arrows. Hap

Hot hap, that weight is for woodies up to 100#, kid arrow weight is 1/2 lb.

OK - just for grins…

I trotted 5-6 dozen arrows across my tester this afternoon, and these are arrows bought at many different times by different people from different manufacturers…

And basically, all of the 600s spined about the same; variance around the shaft was almost universally less than .025”, and frequently less than that — not unusual to see about half.

I was pleasantly surprised to see GT Trad blems right in line with “non-blems”. Bare carbons seemed a little more precise than woodgrain (except Warriors).

Shafts sampled were Black Eagle Vintage & Outlaw, GT Trads & Blems, Warriors, Easton Legacy Carbons, and assorted Beman and GT non-woodgrain.

I don’t have my notes with me, but overall, anything marked at 5/6/7 hundred was in basically one #5 group, and for any given make/model/spine, about 1/2 that. If you buy a dozen, they should be tighter, most likely..

If you have already registered, please

sign in now

For new registrations

Click Here