Climb Safety Grappling Hook

With this project we wanted to create something to increase the safety of rock climbers. Yes, there are harnesses and ropes to catch you, but in the chance they fail, there's nothing. As climbers ourselves we always want to be sure we are safe, and with this device there is that extra step of precaution that can keep climbers minds at ease.

To make this device you will need:

Launcher:

4" PVC pipe (1.5 feet)

2" PVC pipe (4 feet)

4" PVC threated coupler

4" PVC cleanout cap

4"-2" PVC adapter

PVC primer

PVC cement

Drill with 0.5" bit

Spark plug push button

Hairspray

Potatoes

Grappling Hook:

3D printer

Small springs

Paracord

In this first step we drilled the hole for the button to sit in. We went about three inches up from the bottom of the four inch pipe and drilled a half inch hole.

In this next step we put the spark plug push button into the hole we drilled in the pervious step. To do this you need to first take off the inside ring, slide the wires through first followed by the rest of the spark plug until it stops, once its all the way in you would then put the inside ring back on and ensure that it isn't going to come out.

In this step we are putting the launcher together. First put the primer on both ends of the four inch PVC pipe and the four inch threaded coupler. Then put the cement on the pipe, push them together and twist in opposite directions to assure a tight fit. Then repeat the process on the four inch pipe and the adapter. After the four inch pipe has both the adapter and coupler attached, use the same process to attach the two inch pipe to the adapter. Leave it to set for a few hours and then it will be ready to use.

In this step the launcher was made and we needed to test it. We took it out to an open area where we could safely test it and tested it out. After a couple failed attempts we figured out exactly what we needed to do. At first we didn't put in enough hairspray so after a quick google search seven seconds is the perfect amount of spray time.

Now it was time to create the grappling hook. We used OnShape to create our 3D design of the grappling hooks, then the 3D printers at our school to print them out.

In this step we need to bend the springs to fit into the grappling hook we printed. We bent them as shown in the photo and attached them to the grappling hook parts and secured them on there.

In this step we attached the paracord to both the grappling hook and the launcher. We tied the paracord through the loop we designed into the hook. Then also around the base of the launcher.

After having all the pieces we need for this to work we put it to the test. We put the potato on the spike of the grappling hook, pushed it down the cannon, fueled it with hairspray and tested it out.