Balancing long limbs parallel to ground (crane slings)

[JJM IV]

I have been miscalculating (tip heavy / light and butt the same) the dead eye slings when removing long parallel limbs. Maybe the sling angle too great? miscalculating center balance? Curious to rules of thumb too. Thx for help.

 

[evo]

I have been miscalculating (tip heavy / light and butt the same) the dead eye slings when removing long parallel limbs. Maybe the sling angle too great? miscalculating center balance? Curious to rules of thumb too. Thx for help.

Are you using two slings? Three?

A second dead eye with a large(ish) eye attached to the primary with a prussic helps.
Set the butt first then walk out and set the tip. This way if you need to adjust you can adjust the butt one, or worse case go back to the mid point after wire down and adjust the prussic.
Best to have the ball over the estimated balance point and have equal tension around 30 degrees sling angles.
A their sling slightly taught at the balance point if heavy picks as a oopsies backup if slipping prussic is a concern
Often the middle point is tip heavy

 

[Keeth]

Do you have one person rigging & rappelling and another person cutting?

 

[Matias]

Do you have one person rigging & rappelling and another person cutting?

Omg, if we get to crane out this big black oak that we bid, I am gonna suggest that. That sounds efficient as fuck

 

[flushcut]

My crane OP likes me to sling them wide on horizontal picks.

 

[96coal449]

Omg, if we get to crane out this big black oak that we bid, I am gonna suggest that. That sounds efficient as fuck

It works out great. Saves bunch of time and saves me a shit load of pain.
I'm usually the guy cutting in this scenario. The big oak I posted about in the today thread was done this way. I set the first pick for the top, rappelled down, and made my cut. Almost all the rest were horizontal leaders, save one. I set a TIP where I could maneuver around for the remaining picks. That last pick of 30k lbs, both of us set 6 twenty foot eye slings with 2 shackles. 3 straps for each shackle. The guy setting straps was a bit slow. He's not privy to crane work but, it still was done within 3 hrs. If I recall, there were 8 or 9 total picks.

 

[evo]

Do you have one person rigging & rappelling and another person cutting?

I don’t, haven’t done a crane job in years. That and the vast majority is conifer work. Most of the time we brush it out and pick wood.

 

[evo]

View attachment 93777
My crane OP likes me to sling them wide on horizontal picks.

I had a bad experience with wide angle slings. A bigleaf maple lead busted out and was laying horizontal through the crown of the tree. Maybe 40’-50’ long. The longest slings we had were 15’ or about. The stem buckled as the operator was rotating after it cleared the tree. I was working the ground and dodging giant 3’ maple splinters in the parking lot.

 

[flushcut]

Duly noted.

 

[Stumpsprouts]

I have been miscalculating (tip heavy / light and butt the same) the dead eye slings when removing long parallel limbs. Maybe the sling angle too great? miscalculating center balance? Curious to rules of thumb too. Thx for help.

Having the piece butt heavy will generally work out better than tip heavy. So I would ensure the tip is tied adequately far out in the piece, and often have the crane cable up slightly before I tie on the butt so that the tip has more tension. Where the ball is placed relative to COG has a lot to do with how it will behave as well. Each piece is its own unique challenge, isn’t it? If it’s a wide brushy pick I will add a third sling to keep it from rotating. Maybe you can describe your process a little more to help us get a sense.

 

[96coal449]

Yes, 3 slings in an unbalanced, bushy pick, is the way to go. On bushy horizontal limbs, 2 equal length shorter straps for the tip, and a longer sling towards the butt.

 

[cody willard]

Self cuts are king for the horizontal picks. Obviously you want it balanced perfectly, but you can purposely rig it slightly butt heavy, and allow it to lift off the shelf.

You can also make an upward cut on the brush end, then a horizontal plunge cut to rip down a fat branch. After that, you can trigger it with the downward cut at the branch collar as pictured, (third to last picture).

You need Nick Taylors NT Slings and log Equalizer . Incredible adjustability.

Finding the balance point is key, but slightly butt heavy is better then brush heavy IMO.

 

[Daniel]

 

[Jehinten]

I have been miscalculating (tip heavy / light and butt the same) the dead eye slings when removing long parallel limbs. Maybe the sling angle too great? miscalculating center balance? Curious to rules of thumb too. Thx for help.

Take an extra 5 mins on the job and after a piece is down, adjust the slings and re-lift.

See where the slings should have been for a balanced pick and adjust for the next one.

 

[Daniel]

Self cuts are king for the horizontal picks. Obviously you want it balanced perfectly, but you can purposely rig it slightly butt heavy, and allow it to lift off the shelf.

You can also make an upward cut on the brush end, then a horizontal plunge cut to rip down a fat branch. After that, you can trigger it with the downward cut at the branch collar as pictured, (third to last picture).

You need Nick Taylors NT Slings and log Equalizer . Incredible adjustability.

Finding the balance point is key, but slightly butt heavy is better then brush heavy IMO.

good stuff...