Questions: Pulling Trees Over With Pulleys

[StihlRockin']

This doesn't have to be isolated to just whole trees, but for me, mainly tree tops.

I use a two separate pulley system to pull tops of trees over when the climber is ready to go. The mechanical advantage is nice; especially when there's only one guy pulling or just to make the pulling easier.

Instead of describing how I do it, I drew a simple picture to save time. You can see it below:

What I would like to know is, How can I hook up a 3rd pulley to get more of a mechanical advantage?

I was thinking of adding a 3rd pulley on the tree and instead of leaving off where you see the rope ending, it will be looped in the 3rd pulley. Now I like this system. It gives just about all the power I need for most jobs. If I need much more power, I got my ways. LOL! Also, I know about other pulley systems made just for this job, but I'd like to stick with more along the lines of what I do & ask here.(Thanks!)

Can you please describe or show a picture of how you do it using a 3rd pulley? If you do it with 2 pulleys, but a different way, I'd appreciate a look at that too.

Thanks for y'alls help!

StihlRockin'

 

[Wolfking42084]

Why not make the 1st pulley which is around the trunk of the tree and double pulley. Then the line comes out from the top of the tree you're cutting, runs through the first half of the double, up on the rope to a single pulley which is held by a ascender or prusik like you have drawn, and then back down to the other half of the first pulley. Thats how my groundies always do it. It works fantastic. We very rarely use any machines to pull with. The way I described, or tried to anyway, is wonderful and you can pull some heavy loads with a couple guys

 

[Ghillie]

If you only attach a 3rd pulley to the tree (or a double sheave pulley on the tree) it is still a 3:1 mech adv.

If you use double sheave pulleys in both locations you have shown, and run the rope through both sheaves, you can obtain 5:1.

I have a feeling you have another pulley and wonder what you can do with it.

You would have to piggyback the third pulley onto the tow line you show in the diagram. Prussik it onto the tow line, anchor one end of a second rope to the tree, run it through the third pulley and you now have another tow line.

EDIT: This is a compound sytem and makes it 6:1 but is harder to manage and takes a lot of tending.

 

[eljefe]

Re: two pulleys

Hi, Wolfking is right, a double pulley or 2 blocks on the anchor point. I pulled a heavy leaner a couple of weeks ago, working alone. I took what you show in the drawing as the bitter end of the rope, the tail, and anchored it to a porta wrap. Then I hooked a 5:1 fiddle block set from the portawrap to the point below the second pulley- the one you have attached mid line- to the rope with another prussic. This gave me a 10:1 MA. And with prussics I can readjust the point of pull of the fiddle block (my fiddle block only has 50 feet of rope on it). Pull up as much as you can with the fiddle, lock off the bull rope on the porta wrap and reset the point of pull on the fiddle block and go again.
Also, I would use a prussic for anchoring, not a butterfly. A butterfly, when heavily loaded is going to take some time to pick apart, the prussic will fall open when unloaded. And can be moved, if necessary, much more easily. By the way, nice drawing. Eljefe

 

[Ghillie]

Another pulley on the anchor point only redirects, it does not increase mechanical advantage.

Or am I reading too hastily and missing someone's point?

 

[Ghillie]

Hi, Wolfking is right, a double pulley or 2 blocks on the anchor point. I pulled a heavy leaner a couple of weeks ago, working alone. I took what you show in the drawing as the bitter end of the rope, the tail, and anchored it to a porta wrap. Then I hooked a 5:1 fiddle block set from the portawrap to the point below the second pulley- the one you have attached mid line- to the rope with another prussic. This gave me a 10:1 MA. And with prussics I can readjust the point of pull of the fiddle block (my fiddle block only has 50 feet of rope on it). Pull up as much as you can with the fiddle, lock off the bull rope on the porta wrap and reset the point of pull on the fiddle block and go again.
Also, I would use a prussic for anchoring, not a butterfly. A butterfly, when heavily loaded is going to take some time to pick apart, the prussic will fall open when unloaded. And can be moved, if necessary, much more easily. By the way, nice drawing. Eljefe

If you piggybacked a 5:1 onto a "z-rig" like is drawn, you have 15:1.

 

[Ghillie]

Look at figure C or D on page 9 of this Document

 

[treemandan]

The thing about 3 pulleys in this case is , well, uhh, it kinda puts you under the thing you are pulling. Any odd number of pulleys will, I think.
Double pulleys are good but just adding another whole single pulley system is fine as well. Its good to back up the system with prusiick( whole lot of good that will do) but never used a friction hitch to secure a pulley directly to the working line. I don't think that is a good idea.I would use I knot no doubt.

 

[pdqdl]

Put a double pulley at the base of the tree, and a double pulley at your mid-line pulley. Instead of a theoretical 2:1, you will have a theoretical 4:1.

If you need more travel, rig a pulley at the tree being pulled. Tie the midline pulley to the tail of the main line, leaving the rest of the ropes rigged as shown in your figure, and now you have much more travel with a 4:1 advantage.

3:1 advantage? Tie one pulley at the the load (tree being pulled), and one pulley at the base of your anchor-point. Tie the bull rope to the top of the tree being pulled, through the anchor pulley, back through the pulley at the loaded end, then put your groundmen on the loose end. This method will have the most pulling travel possible, but will take 3 times as much rope. It is also the very strongest system, since the rope is tripled for the entire distance, and there are 3 anchor points and the standing end to carry the load.

Myself, I would just get a rope come-along, set a single line, and have about 1000lbs of pull with around a 7:1 mechanical advantage. Nat as fast to pull line with, but better mechanical advantage, and simpler for a groundman to install. It also uses a lot less rope, with the ability to pull the entire distance.

 

[Blakesmaster]

Why shouldn't you attach a pulley midline w/ a friction hitch, Dman? I do it all the time. I atually had to set up the exact system pictured on Saturday but instead of pulling it with my hands I hooked up the ranger. Yeah, it was a BIG tree.

 

[StihlRockin']

I'll make this post quick because I have to go, but I do really appreciate the tips, feedback and help I've received.

After visualizing the 3rd pulley idea I had, I did figure to use correctly as a mechanical advantage, I would need to pull around the 3rd pulley in the direction of the tree being pulled on.... like some have explained. That's not for me. LOL!

Put a double pulley at the base of the tree, and a double pulley at your mid-line pulley. Instead of a theoretical 2:1, you will have a theoretical 4:1.

That's what I was thinking.

Thanks for the help guys. I'll be back!

StihlRockin'

 

[masiman]

...
Myself, I would just get a rope come-along, set a single line, and have about 1000lbs of pull with around a 7:1 mechanical advantage. Nat as fast to pull line with, but better mechanical advantage, and simpler for a groundman to install. It also uses a lot less rope, with the ability to pull the entire distance.

Additionally, it is a little cheaper than all the blocks and no risk of damage like any blocks that might be in the fall zone. Depending on the tree you can set the line from the ground. If you get into attaching blocks to the load, you'll probably need to climb.

 

[Ghillie]

You already have a 3:1 in the drawing.

Commonly called a z-rig.

You will have a 5:1 if you put a double pulley midline and at the anchor.

Measure the distance your tow line moves compared to your load line.

 

[pdqdl]

Ghillie, I don't often make mistakes like this, but I stand corrected.

Yep. that's 3:1, and my suggestions would have made it 5:1

I was not considering the rope from the mid-line pulley to the tree to be a loaded leg of the pulling system. Upon a closer read (or thought?) I realized that was a single pulley attached to the anchor tree, hence 3:1.

[When I hook that up to a tree, we don't use pulleys. Just knots & ropes. The friction going around the tree soaks up any mechanical advantage on the first leg. Oops.]

 

[Ghillie]

Ghillie, I don't often make mistakes like this, but I stand corrected.

Yep. that's 3:1, and my suggestions would have made it 5:1

I was not considering the rope from the mid-line pulley to the tree to be a loaded leg of the pulling system. Upon a closer read (or thought?) I realized that was a single pulley attached to the anchor tree, hence 3:1.

[When I hook that up to a tree, we don't use pulleys. Just knots & ropes. The friction going around the tree soaks up any mechanical advantage on the first leg. Oops.]

LOL... No problem. There are so many different configurations that it can get confusing.

I haven't read through the document I posted the link to yet, but what I have read of it seems pretty good at explaining mech advantage. It is on my list of things to do.

 

[pdqdl]

The silly thing about all these pulleys is the time you loose setting it up. Shucks, all the pulleys and the extra rope probably cost more than the rope come-along.

http://www.baileysonline.com/itemdetail.asp?item=21700&catID=

If that doesn't do the job, you can always put it on a pulley and double up.

 

[pdqdl]

This costs more, but what nice results!

I have one of these for pulling loads. We use a Shindaiwa 488 powerhead.

It gets used more often for moving logs out of tight quarters or up a hill than it does for pulling a tree over. This will easily shag a 500 lb log up a hill at almost walking speed. I used ours two days ago to pull three dead japanese yews. [No digging! ]

http://www.baileysonline.com/itemdetail.asp?item=49470&catID=

 

[BlackenedTimber]

I use two double-sheave pulleys and two Maasdaam 2-ton hoists with prusiks on the working (thats what we call it...? the end your pulling/applying force to) end of the line. use one hoist to apply force and the other to hold the line while readjusting for the next pull, alternating hoists. Killer mechanical advantage and simple to use. Pulled over several 150 ft leaners no problem. didnt have to worry about the ranger slipping (yup, I got one too...) The hoists are 40 bucks each at any Home Depot with a lifetime warranty and the prusiks might run ya 20 bucks each, or make them yourself. Cheap and effective.

 

[masiman]

I use two double-sheave pulleys and two Maasdaam 2-ton hoists with prusiks on the working (thats what we call it...? the end your pulling/applying force to) end of the line. use one hoist to apply force and the other to hold the line while readjusting for the next pull, alternating hoists. Killer mechanical advantage and simple to use. Pulled over several 150 ft leaners no problem. didnt have to worry about the ranger slipping (yup, I got one too...) The hoists are 40 bucks each at any Home Depot with a lifetime warranty and the prusiks might run ya 20 bucks each, or make them yourself. Cheap and effective.

I'd like to see a pic of that setup if you can get one.

 

[BlackenedTimber]

I am gonna havta look around and see if I can find a pic of that setup. I have been out of the industry for about 3 years now, only climbing recreationally and doing the occasional side job for a friend or relative. Nowadays I build wind farms and power transmission lines. I miss tree work though. Alot. :greenchainsaw: