Dynasorb Energy-Absorbing Rigging Line ( Polydyne )
What have we learned about energy absorption when it comes to dynamic activities that test the limits of ropes and wood? For one, we’ve learned that tensile strength alone is not all it’s cracked up to be. For example, no one needs to spell out the result of bungee jumping using high-strength cable instead of (significantly weaker) elastic rope. Although an extreme example, the physics are virtually identical when arresting other falling loads, including tree parts. No, not because the load shouldn’t be injured, rather to lessen forces capable of cracking an anchor point or snapping high-strength ropes. Not only are such shattering forces the inspiration for modern tree cabling systems like Cobra and TreeSave, but they are also the reason many arborists are choosing Dynasorb for wood-dropping activities, too.
In another example, Jamie Goddard of Yale Cordage recently demonstrated on video
a drop test using a 220-pound weight tethered first with dynamic (elastic) line and then with static (nonelastic) line. Tensile strength of the dynamic line was 3 tons, while the static line was 10 tons. The dynamic line arrested the weight six times without failure, while the static line snapped on the first drop.
Dynasorb ( aka Polydyne ) is not drastically different from other arborist-grade rigging lines, only a smidge more elastic, about 3% within working-load range. The first to really tell the difference (especially when there’s ample line in a system) will be the climber. If managed with a lowering device from below, the impact will be noticeably softer. The groundsman operating the lowering device will feel little difference as well if letting the load run properly, but in the event of yanking it to a stop, the difference can be dramatic. Dynasorb’s secret is in the core. Inside is a special blend of high-strength nylon built to come back to shape again and again for unbelievable rigging performance, while the outside feels much the same as other arborist-grade rigging lines. Dynasorb is jacketed in 100% high-tenacity polyester and is Maxijacket-coated for excellent abrasion resistance.Rigging Rope Specification Chart