100m Speedline. Which Rope?

[slack ma girdle]

You will not be able to get enough tension in the rope/wire by hand, to be able to tension the rope properly, let alone with the addition weight of timber/ brash. You might with a couple of hand winches, but it will be painfully slow and hoplessly inefficient.

If there is a footpath running through the site you will be able to get a compact tractor and winch in, that will be able to be removed from site each evening.

Don't go making hard and tedious work harder than it has too.

Somebody on here will have what you need or know somebody who has, that can be sub contracted in.

[Big 'Ammer]

The usual methods for this sort of thing have been discussed.

 

At the bottom of the slope is an access road, the speedline could be tensioned with a vehicle or winch.

 

Hama, the timber needs to be off site.

[Pete Mctree]

Hama, polydine would not be suitable for this application as it's not static. The stretch would mean you would have to "over tension" the line to get comparable clearance with a static line. The extra stretch is what make it a good rigging line, dissipating some of the energy.

In most speedline set-ups people try & get the line taught. This is seldom necessary & puts a massive amount of lateral force on the rigging points, possibly inducing faliure either when tensioning or when extra load is placed upon it whilst rigging

[Pete Mctree]

With some ingenuity, lots of rope, a couple of winches & some muscle I can't see the task being impossible, especially if you can tension lines with vehicles etc

[Big 'Ammer]

With some ingenuity, lots of rope, a couple of winches & some muscle I can't see the task being impossible, especially if you can tension lines with vehicles etc

 

Well, its got to be more efficient than the way its being done at the moment, Pete!

 

50 m speedlines in dismantling are common, I reckon with the right gear the principles could be adapted for this situation.

 

Anybody able to put some figures together for the forces and weights, safety factors etc, using Dyneema or Amsteel?

 

(Please Pete!)

[Pete Mctree]

Too many variables & too complex to throw any numbers about without hours of maths. Common sense is the best tool in this case

[scotspine1]

The loads to be carried would be small and time is not too much of an issue.

 

 

If the loads are small here's a basic system.

 

Any questions fire away.

 

1- Speedline is Dyneema (grey/blue clour)

 

1b - control line (Yellow) could be half inch Yale double esterlon or even climbing line if the loads are light.

 

2 - Pulley blocks in trees (red), Speedline is locked off at the top using a Porty.

 

3 - Tirfor to tension Dyneema, this would only work if you didn't plan to move the top anchor point around continously.

 

4 - Two people hoist loads up to pulley on speedline - Speed of loads is controlled by 2nd Porty at top (which the yellow control line runs through)

 

5 - would the loads automatically start moving down the speedline as you loosened the 2nd Porty? not sure, maybe someone else can add in the finishing touches like a pull rope at the bottom.

 

Reckon could set this system up in around half an hour

 

Can anyone make this picture bigger please?

Edited February 4, 2012 by scotspine1

[Old Mill Tree Care]

I bought an 11mm Marlowe black 'abseil' rope from Chandlery Barge to use as speed line as its static rope.

£55 for 200ft! Brilliant!

[Big 'Ammer]

Cheers Scotspine.

 

I was thinking of tensioning with another pulley at the base of the lower tree and running back to a vehicle winch or just use the vehicle itself?

 

Top and bottom operatives communicating with two way radios.

 

Why not use the set up in your diagram and just let the main line go slack and then tension it up to pick up the pieces, save any manual hauling effort?

 

I would have thought that this slope would be sufficiently steep that gravity would take the load downhill and just a little gentle braking from the control/return line, say a half wrap through a porty would be ok.

[Buzzsurgeon]

If you do get this up and running we need vids!!