why spider legs?

[CHOPPER]

Spiderlegs looks like a good option for taking large awkward limbs as long as you have place to put it down.
Im not an expert but it seems that s-legs are more suited for k-boom operators especially when the k-boom operator is doing the cutting and wants a steady hang when they are so close to it with having to do multiple jobs ie.cutting and controlling a large piece of tree.
I know you K-boom guys dont have 2 sets of hands but how do you climber/k-boom operators cut and control at the same time? Do you have many saw pinches?(hope im not derailing thread)

 

[theXman]

I have much less saw pinches doing it myself.

to be honest, when i heard about mike poor doing it a few years back, i thought it sounded dangerous to be the operator and climber.

after i tried it, i have a very different opinion.

on a pick, I cut, if the kerf starts to sit down, I adjust a little by picking up, if the kerf opening too much and boom down, ect.

Much nicer than directing a guy on the ground running the crane.

there is really no times that the crane has to boom up quickly as the climber finishes the cut; as I've seen in stick boom tree removals; to keep the climber from getting hit by a rotating pick.

I try to do all the picks where i finish the cut and the cut limb just hovers there an inch or so above the cut, waiting for me to move it to the chipper. Sometimes i set them up to slightly swing out away from my location.

if something is really odd and has potential to move around or do something violent, i might cut to the last fiber, then move to another location in the tree, then have the crane take it off.

 

[classictruckman]

[ QUOTE ]
[ QUOTE ]
No the proper term is Center of Gravity. It is point of where the weight is evenly balanced and therefore rotates around.

[/ QUOTE ]

Therefore, where we place the hook of the crane would become the center of mass for the load, right?

In the case of a rigid body, the position of its center of mass is fixed in relation to the object (but not necessarily in contact with it).

Rigid Body

[/ QUOTE ]


According to the artical CofG and CofM are the same thing

"In the context of an entirely uniform gravitational field, the center of mass is often erroneously called the center of gravity "

The craning industry always calls it CofG

 

[classictruckman]

[ QUOTE ]
did you guys read the pound down of free rigging info i sent your way? check out page 4-4, section 4-1.1 http://www.scribd.com/doc/12920346/Rigging-Handbook classic truck man is very right, although a little hard to understand.

[/ QUOTE ]

Thank you so much somebody finally looked it up!

 

[classictruckman]

I would like to hear more about operating and climbing from you and Mike Poor that might convince me.

 

[allmark]

I make almost all my cuts,put the chainsaw down then lift the piece off the tree. It is much safer than the potential of a log coming at you while a saw is running. There is no reason this cant be done with a stick crane using a winch either. It is just easier to see the neccessary adjustments from the cutters position.

 

[classictruckman]

Heres a lift off a Populus canadensis, single steel sling and no movement after the cut. They can't all look like this with a limb in the right spot, but it is possible to balance a pick with a single choker and a little experience.

 

[classictruckman]

Allmark do you operate and climb at the same time too?

 

[allmark]

yes

 

[Colin]

no father down in the article the writer states that sometimes cog and com aren't in the same place. i trust most things out of wikipedia though sometimes the information is purposely erroneous. there is an article on yahoo that proves this. http://pantagraph.com/articles/2009/05/13/news/doc4a09841c4687e852077952.txt the article states that the student fooled wikipedia and the media although wikipedia caught it at a later time.

 

[jomoco]

This video was taken at the rear entrance of the San Diego Zoo on a stormy day. 3 medium eucs were removed with a 120 ton hydro getting the picks on the ground, and a small 15 ton truck crane feeding the chipper and loading the wood.

Every pick was made with a single steel choker and clevis, even the unwieldy picks, one of which my avatar was made from.

http://www.youtube.com/watch?v=fQOUEdSp3Pk

Note the way I hinged the unwieldy picks over allowing them to roll and orient themselves before finishing the cuts so the crane can lift them smoothly.

And before you rag me about not wearing my hardhat, bear in mind that I had a choice between the hardhat and wearing my radio set to communicate with the CO with, I chose the radio. This was before I got my Peltor ProCom plus hardhat/radio system that allows me to communicate with the entire crew with PTT.

jomoco

 

[Mark Chisholm]

Nice work. Thanks for clarifying the whole "hardhat" thing. I, however, would have chosen the hardhat first, but that's me.

The picks you made were just fine, especially with a larger crane capacity than needed. If you were pushing the limits, then the spider legs would have shown even less motion I believe.

Big tree Jo.

 

[brushbandit]

I'm not sold on the safety of the climber being the crane operator. What is the OSHA view or the ANSI standard on the climber being the operator? I doubt they have one and I doubt they would ever approve it.

 

[6t56]

I think I asked the same question,My posts aren't invisible are they?

 

[classictruckman]

Yes now that I think about it if you have an odd shaped piece the CofG could be above it while the CofM is still in the middle of it.

 

[classictruckman]

And we still want some good arguements and explainations from climber/operators

 

[jomoco]

In a trim situation the climber operating the crane to maneuver about in the tree is totally acceptable in my opinion, basically the same situation as a bucket truck.

But in a removal scenario I have serious doubts about the safety factor involved in not having the operator on the crane itself when the pick is made.

I agree BB.

And thanks for the kind words Mark C.

jomoco

 

[brushbandit]

[ QUOTE ]
I think I asked the same question,My posts aren't invisible are they?

[/ QUOTE ]

Yes, I missed your post but went back and looked at it. The operating out of a bucket comparison is interesting but I'm not sure it's the same. Standing in a bucket is a much more controlled environment than being in a saddle tied to the piece your working on. How about being in a bucket, running the saw, and running the crane at the same time. Even that to me is unsafe, too much multi-tasking.

 

[theXman]

i wish i had more time, but don't right now.

I felt the same way as you until I tried it.

I would not want a k-boom moving near me and I not be in control of it. too much of a chance of smashing into the climber or bumping into limbs or such. I as a climber I have the best view of what is going on. I sneak that boom through some of the tightest spots, especially for a trimming tie in point.

Also, a birds eye view is much better than a person sitting in a crane seat. I was thinking about this today while doing a very large dead pine removal with the k-boom.

I can get my picks much more accurate, with me doing them instead of signaling an operator on a crane below.

look for some of Mike Poors videos, he does a great job. a little fast and a little movement for me, personally, but fun to watch.

I really need to get some video out there.

But it might take me getting really sick or injured in order to ever get the time to do so. I was hoping this winter I would have time, and it didn't happen.

"standing in a bucket is a much more controlled environment", ???? That doesn't make sense to me. I hate being in a bucket. I feel unsecure and vulnerable.

 

[Jamin_Mayer]

[ QUOTE ]
I think I asked the same question,My posts aren't invisible are they?

[/ QUOTE ]

I see them!