Science for the win - Decreasing magnet tension in Carter Attraction (and other) Release

KneeDeep

FNG
Joined
Dec 30, 2022
Messages
24
Spent the last two weeks trying to figure out how to get my Carter Attraction release to pop with low enough back tension. This is one of the releases that can be used as a back tension release at high tension settings, or as a command release if you set the release tension below your bow holding weight. Unlike my other releases where you can swap out springs to adjust the dynamic range, this release uses neodymium magnets, and the smallest magnet was still so strong that I couldn't lower it enough to use the release as a command release.

After screwing around for two weeks with spacers and lever lengths and files, I finally figured out that plain old heat irreversibly decreases the magnetic strength of neodymium! Apparently there's this temperature, called the Curie temperature, at which all magnets irreversibly lose strength. For neodymium that's usually between 300*F and 350*F. Sure enough, 20 min at 350*F and the magnet was cooked, 80% loss of strength! Turns out that was way too much and now the magnet couldn't be used as a back tension, but thankfully Carter gives you two magnets. Put the smaller one in the oven at 300*F for 5' and decreased the strength by 30% which was absolutely perfect for me. Low end of range functioned as command release and high end of range functioned as back tension release!

Anyway, this thread may fade into the night until another lost soul finally decides to ask the web how to fix a magnetic based release but thought I'd share my small victory. Science is cool!
 
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KneeDeep

KneeDeep

FNG
Joined
Dec 30, 2022
Messages
24
Measured. I used my phone to record a slow motion video of a small luggage type scale while I pulled harder and harder on a portion of the disassembled release until the magnet separated as it would during release. These numbers don't translate to holding weight, but the setup I was measuring went from requiring 1.65 lbs of pressure to break magnetic connection to 1.15 lbs. That translates to a tension of 12 lbs required to pop the release to ~7lbs required to pop the release (because of levers and stuff inside the release).
 
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