Choosing the Right Rope
Choosing the Right Tow Rope or Recovery Rope
Kinetic vs. Static
Kinetic ropes are designed to stretch up to 30% and provide relief when dynamic loads are involved. Kinetic ropes allow a smaller recovery vehicle to use its speed, weight, and momentum to free a stuck vehicle many times its mass. Kinetic ropes, when used properly, are a safe and efficient way to make a recovery. Kinetic ropes should not be used with steel connection hardware as these can become projectiles if breaking loads are exceeded. Kinetic ropes are typically made of nylon with a double braid cover.
Static ropes have very little stretch. They can not be used to “jerk” a stuck vehicle. Static ropes have a much higher breaking strength when compared to the same diameter kinetic rope. This allows you to pull out larger vehicles with a much smaller and lighter rope. They work best when the recovery vehicle is of adequate size and has appropriate traction and a smooth steady pull can be made. Static tow ropes are typically made of newer synthetic materials like Dyneema, Plasma, or HMPE.
Choosing the right size rope may not always be that easy. When using a kinetic rope, sizing becomes more important. You don’t want to “jerk” your ½ ton truck out with a 200,000 lb kinetic rope as you may lose your hitch. On the flip side, too small of a rope will stretch and break. Static ropes offer more flexibility as you are not relying on momentum and stretch to make a recovery but a smooth steady pull.
An “industry standard” is the rope breaking strength should be 2.5 times the weight of the vehicle being recovered. If your stuck on a sheet of ice you may only need a 1:1 ratio. But, if your 8WD 600HP tractor is suctioned in some deep clay, you should move that ratio to 3:1. What does this mean? In the later situation, your 8WD 600hp tractor with fluid, wheel weights, and attachment may exceed 100,000 lb. This would require a 300,000 lb rope to safely make this extraction and not put unwanted stress on your equipment.
Another variable is what type of recovery/tow vehicle is being used. Must people look at the stuck vehicle to size the rope but that’s not always the case. If you’re using a 250hp tractor to help pull your 8WD with a tile plow, you are really only sizing the tow rope to the drawbar pull of the 250hp tow tractor at a 2.5:1 safety ratio.
Kinetic ropes benefit from a longer length. The longer the kinetic rope the longer it will stretch and more efficiently recovery a vehicle. Standard kinetic rope lengths are between 20’ and 30’. We like using static ropes when possible especially for towing or assisting in tile plow operations. We offer these ropes in various lengths and even custom make them several hundred feet long. This is especially useful to make sure both machines are not in the same mud hole.
Soft shackles are basically a synthetic version of a screw pin shackle or clevis. Soft shackles work great with kinetic ropes and are mostly used for connecting two ropes together. We typically recommend a 5:1 safety ratio on all shackles. One downfall of a soft shackle over a screw pin is that care must be taken when connecting a soft shackle around sharp edges like through a drawbar hole. That said, most people never go back once they see the benefits of the higher safety factor and lighter weight of synthetic soft shackles. Be sure to check each manufacture’s ratings as some already have a safety factor built in.
Please call us @ 608-387-0960 for assistance when selecting the best rope for your operation. Full Pull Rope can supply you with the towing and recovery rope and equipment you are looking for. Check us out at fullpullrope.com.