Tying Poly
Tying Poly
What is the maximum height I can swing from when using this rope?
I am sixteen stones in weight. I have tied the rope to the underside of a bridge so I can swing over water. The rope is three metres long from the bridge to 4 feet above ground level, which is equal to the water level.
Here are the dimensions of the rope:
Blue poly rope
20 mm thick
4 metres long.
What is its breaking strain?
Can I use it safely?
What height can I swing off from?
cheers!
If I swing from ground level I will travel at a certain speed. If I jump from two feet higher, thus giving me more momentum, will this affect the force exerted on the rope? If so by how much.
Being 4 metres long, the highest height you can swing from given the rope would be level to the anchor point, or 4 metres above the water.
I don’t know what the breaking point of that rope is, but I will find the breaking force that you will exert on the rope when you jump from this height, and you can make the decision regarding the rope. Don’t use a rope that doesn’t have its strength published on the package!
Greatest force on the rope will be exerted when you are hanging directly underneath the rope after jumping. This force will be the sum of both your weight and centripetal force.
F=force (N), m=mass (kg), g=acceleration due to gravity (9.8 m/s^2), v=final velocity when underneath rope (m/s), r=radius (which is rope length of 4m), 1 N=0.2248 pounds, 1 kg=0.15747 stone.
Want to find F=(mv^2)/r + mg
First find final velocity
v^2=2*g*height
v^2=2*9.8*4
v=8.854 m/s
4 stone = 101.6 kg
Now plug in…
F=(101.6*8.854^2)/4 + (101.6*9.8)
F=1991+987
F=2978 N
So the force you’ll maximally exert on the rope is 2978 N, or 670 pounds. So find something with considerably greater breaking force, say 1000 pounds or more, and swing away. Plus, you’re over water anyways right? The worst that’ll happen is you get wet a little sooner than you wanted to 
Be safe.
EDIT: Looks like you said 3m rather than 4m. Just plug it in and get a different number. Or use my number, as it’ll be safer. My rating is worst case scenario given your weight at the highest jump height holding onto the end of the rope.
|
|
FLY TYING MATERIALS POLY BALLS MIXED PACK FREE POST £1.99 |
|
|
FLY TYING MATERIALS SMALL POLY BALLS MIXED PACK £0.99 |
|
|
Blue Spot Strong Poly Rope 7mm x 100ft – 30m ideal for tying down Tarpaulin ‘s £4.90 |
|
|
FLY TYING MATERIAL LUREFLASH GREEN FLOATING POLY YARN, £1.99 |
|
|
12 fly fishing tying poly dubbing In neat plastic box £2.99 |
|
|
Blue Poly Rope 8mm x 200m – for tying straping straps holing ty down tight £32.00 |
fly fishing: making a poly caddis
Tying Poly AMAZON PRODUCTS BELOW
|
|
Turrall Fly Tying Poly Dubbing Body Material 1g Pack Black £1.50 A very popular polypropylene based dubbing that is short in fibre and medium in texture…. |
|
|
Turrall Fly Tying Poly Wing Fluoro Yellow £1.50 Turrall Poly Wings are lustrous fibres of continuous filament providing an easy to use winging material. It is excellent for Spinners and Parachute patterns. Approx 100 per pack…. |
|
|
Turrall Fly Tying Poly Flash Synthetic Body Material 1.5m Pack Yellow £1.50 A 2mm wide fine but tough, braided flash material. It is easily used to form bodies on Lures, Streamers and Salmon flies. 1.5 metre length per pack…. |
|
|
Fly Tying with Poly Yarn £12.49 … |
Leave a Reply