Crane Operations/TD

[John Paul Sanborn]

Originally posted by ORclimber
Wouldn't that make it swing to horizontal? What if you want to keep it verticle and then lay it down?

That is on the top of the load, so that it will hang straight up and down.

you set one on the left, one on the right, then drop down to make your cutto spearate

BTW when I said force the hinge, i ment forceing separation. Having the crane teart the peice off.

Durring the last huricane our operator was kvetching about one guy who was having him put 7000# on peices around 3000#.

 

[ORclimber]

Gotcha, thanks!

Have a crane job coming up, it's been awhile. 2 Doug-firs 36" stems 50' tall, 4-5 30' tops apiece. Tight access, single lane drive, doublewide on one side, brick wall on other. 55 ton crane with all wheel steering.

 

[Matt Follett]

ORClimber

Check out the last pic the MB re-posted for me... the dark one, there's the dual sling lift. It makes for a real smooth lift on the big pieces, but takes a min or two to set up. You have to move around the tree a couple times....

Actually on the next lift after that particular one, I just got up on top, and worked from above. It was even darker... and I had even less 'fuel'

 

[Matt Follett]

JPS, yeah for sure on the forcing part, and that's what bounces stuff all about when it finally breaks.

I think lifting hinges and the like take time and practice. Which we don't get nearly as much as felling/swinging ones.

I, as an 'new to cranes' rigger, have been doing rope rigging lifts to improve my understanding, when ever we can set the 5:1 I will, and lift and see what stuff works and try to understand the loadings notch angles, tear off forces required etc. In an earlier post we discussed the notch closing and pop vs the cut the final hinge theorys, I find the cut the hinge to be smoother, but only if I can be protected by something.

Not that we (my little company) are in any position to do so right now, but if your guys were to own a crane, what would be the most practical size?

 

[Kneejerk Bombas]

Originally posted by RockyJSquirrel
Why would it be necessary for the log to 'come off even'??
It would take twice as long to rig 2 chokers instead of one, and it would be more difficult for the groundman to guide the log into the dump truck. It would also take longer for the groundman to unhook and unwrap 2 chokers.

So what would be the purpose for all this??

The climber should be able to drown the ground crew with brush and wood when using a crane if he wants. It genrally takes a lot longer to clean up a pick, than to take one. That said, for the climber to use two straps should not affect the time it takes to make a pick.
A climber might opt to use four straps, two go with the pick and two stay with the climber. As the pick is being move to the landing zone, the climber sets the other two straps. When the hook comes back, remove the straps and put them on your belt, at the same time hook the preset straps up and cut away.
The added safety of two straps is worth the small effort. Doing tree work with a crane is quite dangerous compared to other crane operations because you are dropping loads onto the boom (dynamic). In most other operations loads are picked up (static), and if they are too heavy, nothing happens. In an operation where youy drop too big a load on the boom, bad things happen.
The best way to reduce shock loads is to use two straps, one on each side of the COB, take up the slack and gently apply the load.
Also consider what you do with a crane. Picking huge amounts of weight and lifting them over expensive homes and sometimes people, with straps the crane operator brings with him. You don't know what's been done to that strap (cycles to failure), or crane, for that matter.

 

[John Paul Sanborn]

Dos anyone have a pic of an otopus, or chandelier sling. A multi leg balancer brumeled together to take out whole tops or large laterals branches?

 

[tophopper]

chandelier

JP--

here is a pic of Tom rigging up a chandelier at that speedline workshop a couple of years back. You were there. I have a few others but this one seems to be the best.

 

[John Paul Sanborn]

I've used one a few times for taking a big limb out where a single leg ballancer would not work.

Someone else has that one now. There have been a few cases where I could have used one int he recent past.

i need some heavier hollow braid then what I have on hand now.

(insert fake Chicogo Irish brough)Sean me lad, could ya hook me up there?

 

[tjk]

We often use just a balancer for limb removal. Its a piece of rope (we have a few lengths) with spliced eyes in both ends, Then steel double locking caribiners to half inch loopies. a prusik is the adjuster which is connected to the hook. very easy to rig. Works very well unless your doing real heavy stuff.

 

[Gord]

Here a page of the latest Davey bulletin... I had no part in this but looks like fun...anyone ever used a larger crane for treework?

big crane

 

[MasterBlaster]

Gawd-dam! I wonder how much per hour?

GEEZ!!!

 

[John Paul Sanborn]

I worked with Guy in Raleigh NC for the ice storm in late 2002.

Where we were crane work was problematic having all the utilites paralelling the roadways. Some of that work was a real PITA.