Redwood Blocking/Rigging

[scotspine1]

Very impressive video.

 

cheers

 

Was there no option other than putting the bollard anchor or other at the base of the tree to increase the life of the rope. From the perspective of the video the fall factor would be very high especially with larger sections and a shorter rope as the stems is reduced.

 

How much damage does this sort of work do to the rope and how many loads like this will it withstand?

 

Food for thought!

 

Hi Tony,

 

we could discuss safety ratios, working load limits, cycles to failure, minimum breaking strength, fall factors, green log weights, equipment choice etc at length but I dont like to dwell on these things or put too much faith in the science otherwise you may find that you've rigged yourself into a quandry which could mean serious trouble in the tree. So, instead I've just posted some thoughts on rigging in general, which may answer your questions....

 

1. you can't know the working load limit of any part of a tree. Assume it's the weakest part of your system. Even if you have a good awarness and understanding of Visual Tree Assessment/the body language of trees (being able to identifiy obvious structural weaknesses), there will still be hidden weak spots inside the tree. This should always be at the forefront of your mind when choosing how your going to set up your rigging. Are there any obvious structural defects in the tree? if so, how will you work around this issue? Do we need to use rigging at all? use a MEWP? crane? fell in one go?

 

2. be aware of current industry best practices, think about your rigging setup/equipment and base it around recommended safety factors.....

 

3. choose ropes and rigging equipment that are very strong for the forces and loads that you expect to create....safety factors, working load limit etc.

 

4. what is the objective of the rigging? to avoid damage to structures etc but will it fit in with the space around the base of the tree/landing zone? how much space have you got to rig the timber/branches into? this will help guide you on the sizes of branches/timber you rig.

 

5. What rigging equipment do we have available? what's the condition of the rigging equipment? how much use has that rigging line had? was it badly shockloaded at the last job? has the rigging equipment been in constant daily use on big jobs? does any of it need replaced? do we need to take smaller lighter pieces/branches? do we need to replace the rigging line before we start this job?

 

6. whose working today and what level are they at in relation to rigging experience? how many people on the ground?

 

7. where will I position the block(s) to get the achieve the best results? think the about angles and forces being created, will it swing far enough away from the house? where will I set my tie in point for my climbing line?

 

8. what is the estimated weight of the branches/timber? should I start off rigging small so that I and the groundie can get a feel for the weight? might be a good idea.

 

9. What species of tree are we working on? fibrous wood, brittle wood? how will this affect control of hinges, what type of cuts will I use?

 

10. The client has paid for a professional job, how do we avoid damaging buildings, walls, pots, garden furniture etc? can we move things out of the way/landing zone? plywood the roof of the conservatory?

 

11 what is your acceptable level of risk when making decisions in the tree? take big pieces? will the rigging point tree take the heavy loads? go small? how will this affect the time on the job? ie choose the optimum size of timber/branches that your comfortable with and your experience dictates.

 

12. What is the general health of this tree? or the parts of the tree I'm rigging off?

 

13. are there any underground utilities that have the potential to get damaged during the rigging? are you letting heavy pieces run through the rigging all the way to the ground etc.

 

14. weather conditions? too windy? too wet? will the weather interfere with the rigging to a point where the job has to be stopped temporarily?

 

could go on, hope this helps.

Edited February 25, 2013 by scotspine1