Build a bungee brake

Why do I need a brake

Unless you have designed your zipline to be very slow, thus taking away the fun of it, you need a zipline brake.

A short zipline, and especially in your backyard, should have more than 3-5% slope. Meaning that for every 100 feet, not more than 3-5 feet of elevation loss is needed.

How to build my bungee brake

Most of the time, a bungee brake is enough but it has the disadvantage of sling shot the rider back to the bottom part of the catenary, the belly if you may.  

To avoid this situation, there are ways to set it up with an anti-return system.

You will need:

1. Brake Block (1)
2. Petzl OK (5)
3. Petzl Fixe (1)
4. Petzl Mini-Traxion (1)
5. Petzl Rescue 8 mm Ropes (according to design)
6. Bungee Cord (half the length between the main tree and the anchor pulley)
7. Two anchor points on your main tree
8. One forward anchor point where braking starts

You need is to build a rope close circuit using 3 points of anchors: the brake block, the brake anchor (typically a tree or a ground anchor where a pulley will be attached) and the main tree (or post) where you will attached a one way pulley. 

Your rope should run from the brake block, through the anchor pulley, through the one way pulley and back to your brake block.

To be continued...