Step 1: Do an Inventory of your Hardware
First, you want to make sure that you have all of the parts required for the install. You will need: aircraft cable, slings, cable clamps, a come along (if longer than 250'), a trolley, a turnbuckle, wooden blocks (to protect the trees), and some time and patience.
Slings are optional, as you can use a chain or you can simply wrap the zip line cable around the tree and then secure it with some cable clamps. You always want to install cable clamps in batches of 3 for maximum safety and security.
A come along will only be necessary if the ride is over 250', anything under 250 and you can simply use the turnbuckle to get the proper tension on the wire. If it's over 250', you will need a nylon sling wrapped around the tree which then gets attached to the come along, which then pulls the zip line cable taunt, allowing you to secure it with the proper hardware attachments (ie slings and cable clamps). This is all done on the high end of the ride, and the turnbuckle is used on the lower end. Once you have secured the high end of the cable with the cable clamps, you can remove the come along.
The wooden blocks are also known as tree savers. They are installed to help protect your trees and also to keep the tree from growing in around the zip line wire which would result in a hazardous situation.
The turnbuckle is used on the lower end of the zip line and is used to tighten the cable at the final stage to get it to the right tension. Don't forget to put the trolley on the zip line before you tighten up the wire...although most trolleys do separate and allow you to install them once the ride is up, it's sometimes easier to simply thread the zip line cable through the trolley prior to installation.
One final reminder, is to make sure that you purchase aircraft cable which supports the maximum rider weight that you intend to use with your zip line. You don't want to exceed the weight restrictions as this can end very badly, so please make sure that you triple check these numbers before purchasing your zip line.
That's it for step one, join us as we continue our installation in the next step, calculating ride length and height.