Jump to content

Perfect rigging using a spider's leg


hesslemount
 Share

Recommended Posts

When rigging using a spider's leg (SL) is there a one rule fits all in rigging? I am told and it "mostly" works that use the rigging line to go distal and keep the spider's leg at the butt end where you're cutting. Just for note; both the rope and SL are anchor hitched to rigging crabs with slings on (knotless rigging). The theory then is that both the spiders leg & the rigging rope are taught. Now as long as the centre of gravity (COG) is in between both tie off points; preferably nearer the middle I'd hope, then all will be well; the branch will come down HORIZONTAL!

 

What's other climbers experience of this? With the crane rigs your rigging point is easier and more central. Rigging from the tree you're working on things are a little tighter for space in the third dimension (mostly skywards). So I am saying keep your distal tie off as far out as you can get (without wasting too much energy and climbing time) and your butt end close. Ensure both rigging rope and SL are tight and the COG is somewhere near the middle.

 

If anyone disagrees please help as it's not been 100% or if there's an easier rule of thumb let me know. Some climbers think the SL and rigging end should form an equilateral triangle. Also whilst I'm asking does the law of physics demand that if you have a perfect rig on a SL with horizontal dropping of the branch is there more weight being put on the rigging point that the groundie is attached to; be that a simple wrap (or no wrap), port-a-wrap or whatever? Obviously there are two rigging points on the receiving end.

 

I'm well aware that there are many out there who've thrown their spider's leg in the proverbial footwell BUT used well and in the right situation they're a great asset to the climber's arsenal IF s/he can use it with confidence.

Edited by hesslemount
Link to comment
Share on other sites

Anyone doubting the use of a spider's leg (or a similar set up) please look at Tom D forum reply on crane rigging

 

I like to use a short piece of rigging line on the hook and some spiders on that, that way you can use the spiders when you need to balance a section or just leave them hanging when you don't need them. The spiders are just a piece of 13mm climbing line with a loop either end, you tie a 6 wrap prussic onto the rigging line and adjust the length from there.

 

You can see it here:

 

In this one the top is slung right on the COG, ideally it would have been higher so that it stayed vertical but it was a particularly nasty crack willow, and I couldn't take the risk of the anchor point snapping:

 

Another heavy pick on the COG, a little too much tension here, it jumps off a little....

Link to comment
Share on other sites

  • 3 weeks later...
When rigging using a spider's leg (SL) is there a one rule fits all in rigging? I am told and it "mostly" works that use the rigging line to go distal and keep the spider's leg at the butt end where you're cutting. Just for note; both the rope and SL are anchor hitched to rigging crabs with slings on (knotless rigging). The theory then is that both the spiders leg & the rigging rope are taught. Now as long as the centre of gravity (COG) is in between both tie off points; preferably nearer the middle I'd hope, then all will be well; the branch will come down HORIZONTAL!

 

What's other climbers experience of this? With the crane rigs your rigging point is easier and more central. Rigging from the tree you're working on things are a little tighter for space in the third dimension (mostly skywards). So I am saying keep your distal tie off as far out as you can get (without wasting too much energy and climbing time) and your butt end close. Ensure both rigging rope and SL are tight and the COG is somewhere near the middle.

 

If anyone disagrees please help as it's not been 100% or if there's an easier rule of thumb let me know. Some climbers think the SL and rigging end should form an equilateral triangle. Also whilst I'm asking does the law of physics demand that if you have a perfect rig on a SL with horizontal dropping of the branch is there more weight being put on the rigging point that the groundie is attached to; be that a simple wrap (or no wrap), port-a-wrap or whatever? Obviously there are two rigging points on the receiving end.

 

I'm well aware that there are many out there who've thrown their spider's leg in the proverbial footwell BUT used well and in the right situation they're a great asset to the climber's arsenal IF s/he can use it with confidence.

 

Interesting what you say, from my experience of spider leg rigging it that the equilateral triangle works fine on a pine tree or the like, when the rigging point/pulley is directly above,

 

But this is not always the case with larger, more spread out trees as the rigging point may be over the other side of the tree, what is best to do here?

I am asking in view of learning?:001_smile:

 

There is no doubt that SL is a valuable tool in the arb world done correctly, and Dan Holiday sets it out very simply in this video, for all to learn from:thumbup1:

 

ClimbingArborist.com | Rigging | Spider leg rigging system

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  •  

  • Featured Adverts

  • Tip site reviews

About

Arbtalk.co.uk is a hub for the arboriculture industry in the UK.  
If you're just starting out and you need business, equipment, tech or training support you're in the right place.  If you've done it, made it, got a van load of oily t-shirts and have decided to give something back by sharing your knowledge or wisdom,  then you're welcome too.
If you would like to contribute to making this industry more effective and safe then welcome.
Just like a living tree, it'll always be a work in progress.
Please have a look around, sign up, share and contribute the best you have.

See you inside.

The Arbtalk Team

Follow us

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.