Need some rigging gear

[ApexTreeService]

Bear in mind, too, that the working load limit of a rope refers to the load, not the weight of the piece you're roping down. When using that WLL, a good safety factor for tops/branches is 5:1 (ie; for a 1500lb WLL, don't take pieces bigger than 300lbs) and for negative rigging blocks down 10:1 is more realistic (ie for a 1500lb WLL, blocks no heavier than 150lb). Sounds like a lot, but you'd be surprised at the forces blocks can generate. Branches are generally rigged from above, so they don't create as much of a shock load, and they also often create a lot of 'sail effect' with their foliage which slows their descent and consequently the way the rope takes up the load.

Great informative post.
Does this 5:1 also apply to blocks? If it does, I'm confused as to why the blocks for the same size of rope (example 3/4") have a much higher WLL than the rope to be used in that block.
Samson Nystron 3/4” Hanks has 23,000 lb. average breaking strength = 2,300 WLL
CMI 3/4” Stainless Steel Arborist Block MBS: 40,000 lb, 5:1 WLL: =8,000 lb WLL
I would appreciate if you could clear this up for me.
Thanks,
Rob

Because a block/sling, and the limb it's tied to will have up to 2 times the weight of the piece you are lowering. Imaging a pulley with two ends of the line touching the ground. Now you and your twin brother grab and hang from each end. You both hang there, 200lbs on each rope, but, the pulley has 400lbs on it, so does the sling, and limb that both are you hanging off. Same principal for a port a wrap and a 200lb limb. 200lb on port (or one side of the line/porti), and the 200 lb limb. 200+200 on each side of the pulley is 400lb on the pulley, sling, and limb it's tied to.

 

[B Harrison]

I was going to say you might go with 200' since it will be your only rope, but you got there first.

You should buy it anyway as you need to spend some of the money you have been making this year for tax purposes, just remember you getting a huge discount on everything you buy business wise when you don't have to pay taxes on that dollar at the end of the year.

 

[Carburetorless]

Bear in mind, too, that the working load limit of a rope refers to the load, not the weight of the piece you're roping down. When using that WLL, a good safety factor for tops/branches is 5:1 (ie; for a 1500lb WLL, don't take pieces bigger than 300lbs) and for negative rigging blocks down 10:1 is more realistic (ie for a 1500lb WLL, blocks no heavier than 150lb). Sounds like a lot, but you'd be surprised at the forces blocks can generate. Branches are generally rigged from above, so they don't create as much of a shock load, and they also often create a lot of 'sail effect' with their foliage which slows their descent and consequently the way the rope takes up the load.

Great informative post.
Does this 5:1 also apply to blocks? If it does, I'm confused as to why the blocks for the same size of rope (example 3/4") have a much higher WLL than the rope to be used in that block.
Samson Nystron 3/4” Hanks has 23,000 lb. average breaking strength = 2,300 WLL
CMI 3/4” Stainless Steel Arborist Block MBS: 40,000 lb, 5:1 WLL: =8,000 lb WLL
I would appreciate if you could clear this up for me.
Thanks,
Rob

Bear in mind that the force at the block is doubled, so you'll have a 5:1 WLL of only 4000 lbs, and don't forget your sling, whoopie, loopie you use to rig the block to the tree, as the forces are doubled on it as well.

When selecting rigging rope length you want to think about how far you'll have to lower the highest piece.

If that first piece is 60 ft up, you'll need...

60 ft up + 60 ft down + 20 ft to rig the piece + 60 ft to lower with + at least 20 ft safety margin to keep the guy lowering the piece of out the LZ = 240 ft minimum

You'll need a bit of line on the lowering device as well, so might as well make it 250 ft of rigging line or more.

 

[2treeornot2tree]

When selecting rigging rope length you want to think about how far you'll have to lower the highest piece.

If that first piece is 60 ft up, you'll need...

60 ft up + 60 ft down + 20 ft to rig the piece + 60 ft to lower with + at least 20 ft safety margin to keep the guy lowering the piece of out the LZ = 240 ft minimum

You'll need a bit of line on the lowering device as well, so might as well make it 250 ft of rigging line or more.

WTF are you rambling about. I rig pieces out all the time that are 60' up and I use a 150' long piece of rope and have plenty left over.

You need twice the height of the rigging point, plus a little extra for a tail when you are almost fully lowered. Ex: 60' rig height x 2 120' rope plus 30' tail

 

[Carburetorless]

WTF are you rambling about. I rig pieces out all the time that are 60' up and I use a 150' long piece of rope and have plenty left over.

You need twice the height of the rigging point, plus a little extra for a tail when you are almost fully lowered. Ex: 60' rig height x 2 120' rope plus 30' tail

If you're rigging it straight down to the ground you're right.

If you have to use a zip line to clear an obstacle or just get it closer to the chipper without handling it twice, then you'll need that extra 60 feet.

Then you end up lugging all that extra rope around even if you're only lowering pieces from 40 feet, so like everyone knows, you're better off with a long rigging line AND a shorter one, but the OP is trying to go the least expensive route, but maybe somewhere in our debate he'll find something useful that he can use later. So it's all good.