Tether twister


I've just done my first run of homemade twisted tether:

2 x 18awg equipment wire.

1 X 4H nylon cord .

It looks quite chunky but i was hoping to transmit 200w at 48v down 100m- there might be other wire with thinner insulation. Just starting to think about floats.


Hi ¡¡

Good arrangement.

Have you thought on using polypropylene rope instead of nylon ?

Polyp.... is a lot lighter, and lighter than water. It would reduce the mass of the tether.

While in water, "effective weight" would be even more reduced, due to the rope buoyancy.



Love the winder David. What a neat idea.



Its an old fashioned rope making technique. Nice and simple. It does require 3 operators though.



I tested your idea:

4mm poly rope with 2 conductors as with the nylon version.

In and out of fresh water.

Grams/m IN OUT

Polly 8.3g 26.7g

Nylon 10.5 22.5g

The poly rope seems to be about 6.5mm diameter and the nylon is about 5mm. I am still leaning towards the nylon to reduce drag. I also prefer the cord -think it might last longer.

I am thinking about making the floats out of barrier pipe sections with blanks in either end maybe with an additional o-ring on the seat.


Or maybe just heat the ends and squash them together.

Polypropylene cord dose exist but the only 3mm cord in 100m length i could find was going to cost £50.