Zipline issue

[gilesl.2011]

Bought a zipline trolley rated at 30kn. Small child zipline project..... about 40ft long. Trolley says use 12mm maximum size for steel cable. If 12mm converts to just under .5 in diameter, do I need 1/2" steel uncoated cable, like you get at Home Depot? Sounds a little excessive. The kids using it will be under 50lbs.

 

[cerviarborist]

1/2 inch equates to 13mm. Pulleys are designed for optimum contact and control with specified diameter ropes and cables. You might want to talk to a professional before hanging your kids on something that could hurt them.

 

[Benjo75]

Especially from Home Depot. Wouldn't buy anything life support from there. There's plenty of folks here who will have better advice about what's right.

 

[Tom Dunlap]

Vector loads...learn about them

the fifty pound load isn’t suspended from one single point above them.

Explaining rigging/speed line loads over the years has worn my fingers down from typing.

go with what is advised. The cost saving going smaller is insignificant anyway

 

[Reach]

You might consider buying a cable that is rated for what you need; I’ve bought from this site before: https://www.treehousesupplies.com/Zip_Line_Kits_s/42.htm They’ve done well for me, so I would reach out to them and buy something rated for zipline use. Keep in mind, a 40’ cable properly tensioned could have upwards of 1000 pounds of tension.