vertical speed lines

[mikepage]

Does anyone here have experience with vertical speed lines ? I've been watching some video's on it and it seems like once your left with a spar, you set up a zip line going straight down and then chunk off pieces. the line allows them to drop down to the ground but not go any further from the trunk then the line will let you. I'm not sure what this acheives other than a lot of extra time setting up the rig. why not just rig it off a block ? I must be missing somthing. any thoughts ?

[softbankhawks]

If you dont mind bashing the ground and bottom of the trunk but need to keep the pieces from bouncing away, for example on a slope or with shrubs or buildings around, the vertical speedline is a fast solution. The rope can be attached with a running bowline to the spar so doesn't need to be untied after each piece. Attach sling or slings to said chunk, clip to vertical speed line, attach to friction device and you are away.

[Big 'Ammer]

There is an article about it in this month's Arborist News.

 

I have never utilised it, but I could see that in certain situations it would be a useful technique.

[Mark Bolam]

I also have never used it, but a couple of times I wish I had....

[scotspine1]

Does anyone here have experience with vertical speed lines ? I've been watching some video's on it I'm not sure what this acheives other than a lot of extra time setting up the rig. why not just rig it off a block ? I must be missing somthing. any thoughts ?

 

With normal negative block rigging, you can at times put immense pressure on the stem of the tree, a few climbers have been killed rigging vertical sections because the stem had failed beneath them as the section of timber dropped into the block.

 

with vertical speedlines there's minimal pressure on the stem/trunk of the tree, the rope running down the side of the stem is only acting as a guideline for the section and to stop the piece bouncing away from the tree into a house etc.

[mikepage]

With normal negative block rigging, you can at times put immense pressure on the stem of the tree, QUOTE]

 

thanks, I think this was the answere I was looking for, I have yet to use one.