Smarter, Not Harder - Coldclimb's Slackline Setup

After far too many threads in the slackline forum asking how to tighten slacklines, I figured we need an article on the subject. The systems I used here are widely regarded as some of the easiest ways to tighten a line that exist, mostly because they use very little gear and can be created by one person working alone. I am hoping this article will clear up some confusion among the masses, and add a bit more good information to the site.

What I have done was to spend a few minutes outside setting up my line using three different widely used simple tightening systems. For the most part, I will let the pictures speak for themselves.

Pertinent Information: My line is forty feet long, and about two feet high at the lowest point and five feet high at the highest point. The anchors are two solid birch trees, and the landing is slightly weed-filled ground that I have been turning into lawn with my slacking activity. The line itself is one-inch tubular webbing. I weigh 175 pounds. All systems shown were tightened as tight as I could get them alone.
	The Anchors: At one end of the line, I have a loop tied into the line with a bowline. Most knots will do fine for this, as long as they'll take some serious weight. The end goes around the tree, and the rest of the line passes through the loop, making it adjustable and in theory placing much less stress on knotted webbing, although I have no evidence that says it really does this. It sounds good though. At the other end, I have a length of webbing wrapped once completely around the tree with loops tied in either end, also with bowlines (otherwise known as a "rabbit runner"). The tightening system is clipped directly to this.
The Tie-off: For two of these systems, the line will need to be tied off. What I do is pull as tight as I can, then walk the end around the tree once, or twice if enough slack is available, and then tie it off to the rabbit runner, making as many loops around various points as possible to increase friction and remove most of the tension from the knot. If the knot is taking a lot of stress, it will usually work itself loose, or let line slip through, which is never good as it forces you to retighten the line repeatedly in a session of slacking.

The first system shown here is the Ellington System. The recommendation for this system is to use 9/16in webbing, because it will produce less friction when you pull allowing you to get it tighter. It still works on 1-inch, just takes a lot more pulling.

The line is clove hitched to a pair of carabiners at a point about five feet away from the anchors. Two carabiners are used to make the clove hitch removable after slacking hard. If only one biner is used, you'll need fingers of steel to get that knot undone. Remember this. The tail end of the line then goes through one biner on the rabbit runner, then loops back and goes around one of the cloved biners. From there it goes back to the first biner on the rabbit runner and loops through it again, going over the top of the previous loop and making a full circle. This method continues until you have three complete circles of webbing around the two biners, each loop going over the top of the loop before it. Here's the cool part. When you tighten this line, if set up correctly, the loops will roll around and the top layer will go under the other layers. When you let it go, it is automatically locked off tight! No messing with knots while holding tension, which is very nice. The only downside is that you'll want either 9/16in webbnig, or a strong friend to help you pull your 1in.

The photo on the left shows the three loops before tightening, and the photo on the right shows them after tightening. Under these two pics is a blended composite of the drop in the middle of my line after tightening this system by hand, alone.

The second system is simple use of two carabiners to add some mechanical advantage (and a third, to keep that darn clove removable). The line is clove hitched as with the Ellington, about five feet from the anchor. The tail end goes through a biner on the anchor, back through one biner on the clove hitch, and then goes to the power, which would be me. I yard on the end of that line as hard as I can, then tie it off using the method described previously. The photo on the left shows the system in use, and the photo on the right shows the drop in the middle of the line after tightening as hard as I could. It should be noted that the mechanical advantage of this system is not as much as the next system shown, and that the amount of friction is severely dropped as well. What this means is that while there is less friction to pull against, you also exert less force on the line. In addition to this, the line is harder to tie off without letting some slip through because of the lack of friction.

The last system uses the same idea as the two biner system, but with four biners instead. The line runs in a zig-zag fashion through all four biners and is pulled in the direction of the anchor. While there is a bit more friction involved trying to pull this tight, there is also more mechanical advantage. I've found in my own experience that this works better for one-person tightening. The friction actually helps when it comes to tying off the end of the line, because it takes much less force to hold it and keep it from slipping while you tie the knot. This is my method of choice. Once again, the photo on the left is the tightening system, and the photo on the right is the drop in the middle of the line when tightened by me alone.

There are many different commonly used methods out there, and specialized tools with which to tighten and lock off lines. I'm just hoping this article will be a help to the average person setting up ordinary lines without getting too complicated or using a ton of gear. I hope it has been useful to you.