Ever wondered about the loads on a zip line you may have rigged?
I’ve got hold of a small portable load cell which I used last week when out with a group to measure the forces on the top end of the zip line during rigging and use. Here’s a copy of the graph generated from the readings.
You can see how I managed to tension the rope the rope with a 5:1 system initially by myself, then with some help.
I had 1 teacher (approx 100kg) and 10 students (primary school kids around 30-40kg each) down the zip line, with the teacher first. You can see the loads shoot up as the teacher reaches the mid point, then the tension of the whole system drop (almost by half!) as I suspect knots tighten up etc. This then remained reasonably consistent throughout the session.