Rigging limits

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david1332

david1332

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whTs the heaviest piece of wood you would negatively rig with a rope with a MBS of 11,500 pounds a port a wrap and 105kn MBS block. Rope is obviously the weak point in the system.

I know the swll would be somewhere around 1150 pounds, but I know a piece puts more than its actual weight in force on the rope when it falls.
 

Del_

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So I can safely rig out 1000 pound pieces? Obviously let it run on the porty lol
That would be like what 4 wraps?

Multiply the piece weight by the feet dropped then add back in the piece weight.

So a 400lb. piece dropped three feet = about 1,200 to 1,600 lbs.

Letting it run reduces the load significantly.
 
david1332

david1332

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Multiply the piece weight by the feet dropped then add back in the piece weight.

So a 400lb. piece dropped three feet = about 1,200 to 1,600 lbs.

Letting it run reduces the load significantly.
Yeah I read that somewhere. I think arborpod?
So I would safely max out around a 300-500 lbs piece depending on how well I can let it run. That's pretty damn good for a 1/2" rope and a good ground man. Thanks Del!!
 
david1332

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On another hand, anyone ever use 1/2" New England Sta-Set? It feels more like 3/8" and definitely is smaller than my 1/2" stable braid...

i just bought a 200' hank and was very surprised when I felt it
 
crotchclimber

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On another hand, anyone ever use 1/2" New England Sta-Set? It feels more like 3/8" and definitely is smaller than my 1/2" stable braid...

i just bought a 200' hank and was very surprised when I felt it
Yes, it's my primary rigging line. It will fluff up with use more than stable braid does. Nice rope, my coworkers are starting to use it too.
 
BC WetCoast

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When you get up into those heavier weights, especially if you are butt hitching them, the two places of weakness I worry about is the tie in point where your block is and the quality of the strap attaching the block to the tree. The tie in point, because there could be hidden defect and the block strap cause it probably has more stress cycles than your rope. For us, where rigging gear is shared between crews, I'm never confident that some bozo hasn't overloaded something, so I always rig lighter.

Small pieces = small damage
 
david1332

david1332

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When you get up into those heavier weights, especially if you are butt hitching them, the two places of weakness I worry about is the tie in point where your block is and the quality of the strap attaching the block to the tree. The tie in point, because there could be hidden defect and the block strap cause it probably has more stress cycles than your rope.

Small pieces = small damage

I'm the only one who uses my equipment so I know what it's been through. I totally agree with that though. Better safe than sorry. I try to bomb out as much as I can. Most of the time I atlEast have enough room for a verticle speedline.
 
beastmaster

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I worry more of tree failure then equipment failure. Remember your putting double the weight of the force on the pulley (and what its tied to). Be sure to factor that in.
Im a big fan of dynasorp rope for negitive rigging. Im convinced its saved my life a time or two.
 

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