Review: Ace Spine Master Spine Tester

Having correctly spined arrows is very important in archery. It's even more critical when using wooden arrows in selfbows. Spine refers to the stiffness of the arrow, which is gauged by measuring its deflection when a 2# weight is applied to it. The unfortunate thing is that most spine testers will run you $200-$300 and the prices are always going up. That may seem pretty expensive, but a spine tester is a fine tool, requiring exact accuracy and calibration. The Ace Spine Master Spine tester is an affordable alternative for $90-$114.

I put the Ace Spine Master though it's paces. I tested about a hundred or so Port Orford Cedar arrows and some other miscellaneous shafts that I had sitting around. I also have some ash and maple shafts but decided to test those another time. The bundle of 100 Cedar shafts were bought as group years ago and apparently machined spined at 55-60 pounds. Machine spining is when shafts are randomly tested, so some shafts might not be spined properly.

Out of 100 cedar shafts, only a dozen spined below or above the 55-60# range. I set those arrows aside to use in lighter/heavier bows. The rest of the shafts all spined within 55-60#.

Then I tested the finished arrows in my quiver. They all tested fine except for one that hit 75#! That would explain why one shot in my groups would fly to the right. I pulled that arrow out and set it aside.

The Ace Spine Master is hung on a wall. I hung mine on a board and clamped it in a vice for easier portability (and less holes in the walls). When spining shafts it's best to get three spine readings to ensure accuracy. Place the shaft on the tester, zero it out, then test it, rotate the shaft 90 degrees, zero out the tester again and take another reading. Do this three times and average out the results.

Aside from spine, the weight of the shaft is also important for consistency in your arrows. I use a hand scale which works for my needs. After spining your shafts you can then weigh them. You can then arrange the shafts in groups that are closest in weight AND spine. The more consistency you have, the more consistent groups you will get when shooting.

I would highly recommend a spine tester. It's a great way to ensure that all the arrows you use are a closely matched as possible. The Ace Spine Master is inexpensive compared to other spine testers and does the job very well. You can purchase it directly from the source (made in the USA) or other traditional archery vendors.