This fun zipline is great for kids and adults. My zipline zips all the way to the other side of my lawn where I go on a homemade rope bridge that takes me to another bridge that leads to my tree fort and then you walk on slap lines to get to my trampoline. It's like going to a high ropes park but you don't have to pay.

Cautions.
Avoid travel being too fast so as they collide at landing or to slow (if elevated) that they get stuck away from landing (watch/adjust slope as needed). Avoid dangers below zipline for when kids fall off. Don’t have elastic type anchors or other lines in high tension to slow stop rider.. if they break the loose ends could whip back at the rider and cause serious injury. Ensure no one ever touches the zipline or they could lose finger or hand.. ideally, the rider (seat or handle) is well below zipline to avoid anyone touching the line (note the purchased ziplines typically have handle right at zipline.. super bad.. but at least a defined place to keep hands).

Supplies

.hammer

.screwdriver

.surveys level

.hand saw

.wrenches

.2 x 4 wood

.deck screws #8-3”

.galv. Nails

.slackers zipline kit or steel cable (4.8 mm dia.) and 9 crosby clamps and steel runner pulley (double inline pulley suitable for running on steel cables! Not climbing pulleys for ropes)

.turnbuckle 6-8 inches

Step 1: Step 1

Select a site, based on length and slope. The distance should be 50-100 feet. Slope 3- 5 percent (can be checked with the surveyors level). Height should be low enough that smaller riders can touch ground or platform at both ends when on cable and not so high to bump into riders buts/knees. Look for trees with a minimum of 12-18 inch diameter at the connection point and healthy tree. It can be an elevated platform to the ground or elevated platform to elevated platform.

Step 2: Step 2

Build a starting platform. For the platform, you can use 2x6 inches lumber (on sides) between trees with galv. Nails (4-5 inches long) to construct floor joists (3-6 feet length). If there is only one tree (or branch) available you can use posts for other ends of the platform, posts can be 4x4 inches treated lumber. They should be founded in 12-36” deep hole (depending on soil conditions) with brick or concrete footing and supported to joists with triangle braces constructed of 2x4” lumber.

Could construct end pieces with horizontal timber supported on each end by triangle frames. This approach often did at playgrounds, but not often at house yards, needs to resist the pull of the cable, such as with an anchor cable from the horizontal member pulled back with a cable to some anchor (such as a buried horizontal steel plate/rod or duckbill type anchor).

Step 3: Step 3

Nail 2x4s across joists to construct platform floor, leaving 0.25 to 1-inch space between 2x4s.

Construct railing with 2x4s, 36 to 42 inch high, leave open where the zipline goes.

Step 4: Step 4

Construct a landing hill or platform. The platform can be the same as take-off except it should be longer to allow a greater range of ending location ( 12 feet plus or minus ). Might slope the landing to account for smaller and larger riders.

Step 5: Step 5

Connect seat to a pulley with 1) vertical rope (i.e. Slackers zip line) or 2) horizontal log to the pulley with rope on both ends of the log (forming a triangle pulley at top, rope on sides, and log on bottom) for riders to hold onto log under armpits, or 3) with a fixed loop to connect daisy chain and seat or body climbing/work harness via locking carabiner (i.e. higher/longer ziplines). Have a vertical rope or line that will extend from pulley to a height that will be reachable for helpers on the ground.

Step 6: Step 6

Wrap zipline cable around the starting tree. Connect the loop of cable with 3 opposing Crosby clamps. Hammer or wooden chimes for example 2x4s. Construct a loop around the landing tree, through the turnbuckle, attach with Crosby clamps (add shims between tree and cable), insure both of the loops are not too tight around the tree, loop connection should be 1 - 2 tree dia. Away from the tree. Thread pulley system on zipline cable. Connect the main zip line cable to the other end of the turnbuckle using the remaining 3 Crosby clamps. The cable can be tight. To end the ride at end of zipline cable, wrap old inner tubes near Crosby clamps as the bumper and slope should not be too steep that heaviest riders swing up and hit face on cable. Alternatively leave slack in the cable to get the rider to up cable past slack point to slow the rider down, then landing location will be at that location. If using the slaker line, you may need some galv nails or ‘u’ nails to hold the cable in place. (Alternatively, the cable can be attached to trees with a galvanized threaded eyelet through the tree with bolt and a metal plate on another side of the tree. this method is good but prevents the adjustability of cable slope).

Step 7: Step 7

Steps 7

Test zipline; first by heavy person hanging on cable, then with a rider on the zipline with a strong and heavy helper holding the hanging down tether rope to control speed or rider. Try this approach with all new riders to ensure not too fast (heavy riders may be too fast and lighter riders may not make it to the end). Adjust slope of cable (by hammering shims) to get speed correct.

Step 8: Step 8

Step 8

Now done, but the rider has to bring pulley back using tag rope after each run. Instead, a pulley could be added near the take-off cable (or higher) and then a small pull back line (2 mm cord) lined from rider pulley to this new pulley and then add a weight (such as cloth bag of rocks) to pull back pulley. This weight will slow down the rider, the slope will need to be greater for the zipline. A set of inline pulleys at top and at weight allow weight to get travel without being the same height above ground as zipline is long. Furthermore, a secondary line with additional weight could be attached to the weight bag to slow down the rider at end of zip ride.