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Opposite view of the split. Tree was approx. 4' DBH. Just to the right of the trunk, you can see the neighbors pool pump house. Notice the limb going directly over the pump house. There were 2" PVC pipes exposed outside the pump house that we had to be careful not to break.
 

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This is where the tree was resting, in the neighbors American elm and white ash. Directly below the resting point is the neighbors aluminum fence. This pic also shows the narrow landing zone, 10' wide at it's widest point.
We have a 200' X 3/4" DB tied (orange) close to the resting point. The rope is anchored in another neighbors 24" white ash approx. 175' away. This rope goes to a 3/4" CMI arborist block anchored about 9' up to protect against peolpe from running into it and to get the rope to run down to the large porty anchored near the base, so we could use a Lug-All winch to tighten it. We doubled the wirerope on the Lug-All to get a 1,500 lb. pull and we used every bit of the 1,500 lbs. of force.
 

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Now we get to the avatar pic.
I was the one doing the topping and engineering, so I don't have any pics from the topping.

How we got the job:
The homeowner called her landscaper when she saw the tree was damaged. The landscaper called numerous tree care firms for quotes. Long story short, we found out the following morning that we got the job because we were the only ones to give a quote. Our quote was a T & M not to exceed $. We figured it would take 1/2 day to set-up the rigging (2 persons) and 2 full days, with 5 persons, to get the tree down and out. It was approx. 80 yards to the clients driveway, which was the closest access.
I'll try to explain the purpose of each rope and block, starting from right to left. The furthest right rope (smaller yellow DB 9/16's") is a guy rope to help stable the tree the rigging was set in. It is anchored to a porty 2 near the base of a neighbors tree. The 2nd yellow rope, a 5/8" DB, is set-up in a DWT to help hold the spar up. The DWT block is a 1" Hobbs and the elm tree block is a 5/8" CMI. It is anchored near the base of tree in the clients yard with a porty 3.
Next, in the elm, is a 5/8" DB (red/orange) used as a 'slide line' to help guide the spar down to keep it from going beyond the landing zone. We didn't want it going anywhere near the flimzy aluminum fence.
Above, in the elm, is another 5/8" CMI with a 5/8" DB used to help hold up the spar. Above that is the lowering line (1/2" 3 strand) with a spliced ladder snap for the brush and smaller logs.
 

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Wow Norm, that was surely a tight spot to work in. Excellent job!

I love the use of technical rigging that these kind of jobs allow us to do. Engineering a tree removal of this magnitude takes a great amount of skill. Your plan looked well thought out and safe, given the condition of this tree.

Question, why did you choose to use the Lug-All winch over the GRCS?
 
Another question Norm (and I’m in no way criticizing your work), just trying to understand the engineering behind it.

In the fourth photo, you have the 1” Hobbs block setup with the DWT and a 5/8” CMI block as a redirect coming from the DWT.

Would it have been better to have had the two blocks reversed, so the redirect block (which receives double the load) would have had a higher strength rating?

Obviously you weren’t taking very large pieces that would have pushed the WLL of your rigging system. I’m just curious
 
the whip block (1" hobbs) takes twice the load of the primary block in the lowering system. the load to the primary block is 1/2 of the load on the whip block. and if the primary block is setup with another pulley behind it to redirect the load to the ground then the load factor on the primary block is even smaller. to help clarify what i'm talking about think of a crane. the block is set to give mechanical advantage and to double the wll of the rope he could have used the lowering system to stabilize the guy tower (rigging tree). look into guy derricks and gin poles and how they work its amazing what you can do with a little knowledge and a couple of blocks
 
Jeff, I see what you are talking about with the way that Norm has the DWT set up. I was thinking that the top yellow anchor line coming from the Hobbs and going to the elm was acting like a becket would on the 5/8" CMI block, but that isn't the case.

Basically both blocks have the same amount of reaction force acting on them as is shown in the Double Whip blocks on the right side of the page in the example link that I have attached below.

http://www.btinternet.com/~fourthgill.seascouts/dwhip.htm
 
[ QUOTE ]

Question, why did you choose to use the Lug-All winch over the GRCS?

[/ QUOTE ]

The Lug-All could be attached directly to the retension bar on the porty, and once the porty was snugged up, the Lug-All could be removed.
If a GRCS was used, it would have to stay on the tree. Didn't want to chance leaving a $2,300.00 device over 2 nites.
Using the come-a-long tensioned up the rope pretty good. Once the piece resting on the elm was cut, the spar only dropped 6-8".
 
[ QUOTE ]
Another question Norm (and I’m in no way criticizing your work), just trying to understand the engineering behind it.

In the fourth photo, you have the 1” Hobbs block setup with the DWT and a 5/8” CMI block as a redirect coming from the DWT.

Would it have been better to have had the two blocks reversed, so the redirect block (which receives double the load) would have had a higher strength rating?


[/ QUOTE ]

The 1" Hobbs is at 1X the load.(the 2 parts of rope 'share' the load)
The 5/8" CMI rope had 1/2 the load going into it, times the rope angle, which is very shallow. So, yes, they are pretty much seeing the same amount of force.
Using a DWT reduces the force at the lowering point (the stationary block) by roughly 25% (depending on the rope angle at the stationary block). Reducing the force on the rigging tree was my goal.
Keeping the big, heavy 1" block outta my way was also a goal. I used every block I had on this job. There's 5 in pic 4 alone(the slide line block is blocked by the end of the log, but you can see the eye sling for it). I like using my rigging gear on my jobs, cause I know the history of each piece. If something fails, I can only blame myself.
See attachment:
Very good observation, Chris.
 

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Thanks for sharing, Norm, that's some rad rigging there. I must say, I do enjoy intense rigging scenarios. If I would have been in your area, I would have bid that tree. But you would have gotten the job, you are apparently a master.

Thanks for the in-depth explanations and pictures. Highly illuminating.
 
[ QUOTE ]
If a GRCS was used, it would have to stay on the tree. Didn't want to chance leaving a $2,300.00 device over 2 nites.

[/ QUOTE ]

Don't blame you there Norm. That's one piece of equipment that you don't want to get stolen!

Another question. Did you think at first that you might have to support the butt end with some sort of "A Frame" cribbing, or were the attachment points at the butt end sufficient to manage any extra weight before the support rigging was set up in the Elm?

I know that the tip was hung in the other trees, but was there concern about the butt end separating from the trunk? I've attached a link to one of your posts from a few years ago where you used the "A Frame" for those who have never seen this done before.

http://www.treebuzz.com/forum/showflat.p...748fa83bfde0612
 
"We" (Jerry Kelly and me) put our heads together and thought the rigging points in the elm and the neighboring white ash were suffice to hold the spar tip. The 3/4" DB, from the ash, held more weight than "we" thought it would. I was glad we chose to use that ash tree in the end.
 
I didn't realize why this was a good thread until now. I just thought it was a, well, avatar thread.

I love seeing creative rigging. They get more creative when the situation is more creative. So, one's experienc in rigging will be best to pull off a job like that.

Nice work Norm!
 
For the sake of not derailing, I'm going to move this to another thread.







How often to people use lowering devices up high in the tree, rather than blocks with their force multiplying effects. Seems like a way to keep rigging forces down. The upper lowering devices would need to get tied off to another one down low. The difficulty would be to get the correct amount of friction. If a bucket is used, the adjustments would be easier.

Often people have more blocks that friction devices, but it might be very useful in some situations, especially when the rigging points are not as beefy as would be preferred.

OF COURSE, I'm not second guessing Norm here. It looked like a master rigging plan. Just something that came to mind.
 
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