How to Tighten a Zip Line Cable
If you are thinking about installing a backyard zip line, learning how to tighten a zip line cable is something that varies from person to person. Though the concepts remain the same for everyone, your tools will change depending on the length of your zip line cable. We are going to go through all of the methods of making your cable taut.
A cable being too slack (or loose) will slow down your rider a lot of faster than if it was taut (tight). It will also create cable sag which may result in your rider dragging on the floor. Everyone has different goals for their zip line, but typically dragging takes away from the experience! Here are 3 ways to effectively control the tension on your cable.
We are starting with the free method. As you probably guessed, this technique requires a little bit of pulling. You don't need any tools, but two people is highly recommended. On top of that, we only recommend tightening a zipline by hand with zip line length of around 100 feet. Any longer, it becomes difficult unless you are superman!
Wrap the end cable around the end anchor, which could be a tree or post and while you are creating tension, you can have your buddy install a cable clamp. One cable clamp will be sufficient to hold the cable up, but three clamps are necessary for the zip line to be safe to ride.
Once you have three clamps on the cable, one trick to get a little bit more tension is to move the cable clamp closest to the tree closer to the tree. This is achieved by squeezing the split zip line cable and sliding clamp over. Be sure to readjust the other clamps to ensure they are evenly spaced and tightened.
What is a turnbuckle? A turnbuckle is a device for adjusting tension of cables. It has two threaded eye bolts with each side having opposite threads. How can this be used for a zip line?
The turnbuckle is placed near an anchor (tree or post) and works in conjunction with a cable sling which wraps around the tree and attaches to one end of the turnbuckle. The other end of the turnbuckle attaches to the main zip line cable.
When first operating a turnbuckle be sure to unscrew the ends to open the turnbuckle. These will be tightened later on to bring the cables closer together. Attach one end of the turnbuckle to the main cable line. The main cable line typically has a swage end, or you can create a loop with cable clamps shown above with a cable thimble. The other side of your turnbuckle will attach to your cable sling that is wrapped around your end anchor. Tighten the turnbuckle by twisting it with a wrench, your hand or a screwdriver.
Cable Come Along or Cable Tensioning Kit
There are many different names for a Cable Come Along. Some common names are cable puller, winch, ratcheting tool, or cable tightener tool. All of these have the same purpose, it represents a mechanical way to achieve tension in a zip line cable. If your zip line is over 150', it is strongly recommended you have a cable come along.
To properly explain how it works, I will refer to the main zip line cable; riders will be on the main line.
The main idea behind a cable tensioning kit is to use the kit to temporarily create tension towards the end anchor so the main zip line cable can be tied off properly. The come along tool will temporarily attach to your end anchor via straps and the main zip line cable via a temporary cable clamp or a cable grab. This will provide a temporary connection to ratchet the main zip line cable tight. From there, take the dead end of your main zip line cable, and fasten it around the tree. Once secured, you can remove the come along line and now you should have a fully set up zip line.
Congratulations you have just learned three ways on how to tighten your zip line cable. You can mix and match these methods together as well. It is very common to have a turnbuckle with a cable tensioning kit for fine tuning. Please check out our tutorial on how to build your own homemade zip line. Always be safe and happy zipping!