There are many different ways of setting up a slackline. The method I will describe below is the one that I use, and one of the biggest advantages of it is that there is only one "knot" in the entire system, and the line can be easily adjusted, or torn down.
Items you will need: (click the links for websites to order the supplies)
- Three "oval" carabiners (referred to from here on out as 'biners)
- A long piece of 1" tubular webbing, (I use 70') Military or Climb-Spec, doesn't matter, for walking on
- A shorter piece of 1" tubular webbing for attaching to a tree (I have two different pieces I use, depending on the size of the tree, I believe they are 10' and 20')
- Two strong and healthy trees, however far apart you want to walk, with ground beneath them that you don't mind walking/jumping on in bare feet.
You can purchase the webbing and 'biners anywhere that sells climbing materials, harnesses, rock climbing shoes, rock climbing ropes, etc. If you go into the store, they will also cut the material for you to any length you need for free. It is usually around $0.30/foot.
***It is VERY important that you do NOT try to cut the tubular webbing by yourself.***
Tubular webbing is a specially designed material which can support (usually) around 4,000lbs. The device that is used to cut it does not actually CUT the material, it MELTS through it, which maintains the strength of the material. Even cutting it with a scissors and then melting the ends with a lighter does not do what you need it to, and can lessen the integrity of your materials increasing the chance for failure, and possible injury.
The first thing you need to do is prep the short line to go around the tree. I use a water knot, also known as the tape knot. This is the only part of the entire system that is slightly difficult to undo at the end of the day, and to be honest, I just don't take it out anymore.
You will use the water knot to make one loop out of one of the shorter pieces of tubular webbing--instead of tying two shorter pieces together to make a longer one, which is what this knot is typically used for--and instructions for tying it can be found here.
When you are done, the knot will look like this.
And you should have one loop out of a shorter piece of webbing, looking like this.
After that, loop the piece of webbing around the tree, and pull a free end through to make a "lasso" around the tree. You don't need nearly as long of a free end as what I have shown here, the tree I used was just barely too big for my small piece, and much to small for my large piece... so this is what I got.
Attach one of the three carabiners to the free end of the loop, and set it on the ground for now. Pick up the long piece of webbing and walk over to the other tree.
Next secure one of the other carabiners to either end of the long webbing. I use a girth hitch. A video can be found here, or you can look at the pictures I provided below. Note that in the video he adds an additional "safety" knot. You can do this if you wish, but I have never had these knots fail for this use, and you're only about 2 feet off the ground if they do.
Next secure that end of the slackline to the tree that does not have webbing around it already by wrapping the webbing around the tree, and clipping the carabiner to it.
Next attach another 'biner to the webbing, close to the point where the short webbing stretches out to (where you attached the first carabiner). There should be approximately 5-10 feet between them, depending on how far apart your trees are.
Then clip the webbing into the first carabiner like the picture below. Notice how I am careful to keep the line from twisting between the two carabiners.
This next part is incredibly easy once you know how to do it, and very easy to explain in person, but rather difficult through pictures and text... I will do my best.
Bring the line back and clip it into the third carabiner, making sure to keep the line from twisting. You have now started a circle, actually more of a spiral, out of the tubular webbing, and it should not be twisted at all. If the little threading on the webbing is on the inside, make sure to keep it on the inside.
Next go back to the first carabiner and clip in again, once again careful to keep the line from twisting at all. This part is what will keep the slackline up, there are no knots in it, but the friction from the line being pulled will keep it tight, and any twists in the line make that friction less effective.
When you clip back in to the first carabiner, be sure that the line you just clipped in is BELOW all the rest, to continue the spiral that you're making, so the free end is always to the INSIDE of the spiral. That way, the outer parts will cinch down on the free end and stop it from slipping. (You can see pictured below me holding the "old" line out to show that the newest line clipped in is on the inside.)
Finally go back to the third carabiner and do this again, once again making sure to keep the threading inside (or outside) to stop the line from twisting, and put the newest clip-in line BELOW all the rest. Pictured below.
You can repeat that as many times as you wish to take up extra line, but I usually do exactly what I just showed and leave the extra laying on the ground.
Finally, pull on the free end. As you pull, the two carabiners will get closer together, and the "slack" in the line will start to take up.
Get some friends to help pull the line tight, and there you have it!
Get some friends to help pull the line tight, and there you have it!
