How Much Lean Can Be Overcome By Pulling?

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lxskllr

Treehouser
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The crane operator wants me to drop a tree for him. He asked last year, and I called one weekend, but he said he was busy. The way he said it made me think he wasn't interested anymore, so I didn't pursue it. Well, it may just be the way he speaks, cause he asked again.

I haven't seen the tree, and he hasn't been much help in describing it. It's leaning over a fence by some amount, and he owns both sides. When I talked to him last year, I suggested climbing til I got past the fence(he says 15'), topping it there, then dropping the rest on the side it's growing on. He's very interested in keeping it on the side it's growing on, and has suggested twice pulling it with his tractor. Since I haven't seen it, I can't say "easy", "maybe", or "LoL no". The middle option is the most problematic, cause things could go either way.

Here's the manufactured setup, since I don't know what the tree is.

2' DBH oak
Height that would get you a 2' tree, so pretty tall
A forest setting. Fenceline with pasture on one side, and forest on the other
A tractor of unknown size, but I'm guessing a hard working hobby farm tractor

If I set a line 70' up, what would your estimate be for how much lean could be overcome with a tractor and forest loam as a traction surface? Most straight forward would be shooting a line up, cut and pull. More time consuming would be climb up, set a snatch block, anchor and pull. Easiest of all might be take down the damned fence, fall it into the pasture, then cut it up in tractor size pieces. But I don't know what kind of fence it is. Wood is easy, and high tension wire tough. So, how much lean?
 
Theoretically, any amount of lean can be overcome, given all aspects are covered. The biggest issue is that if it’s leaning “too much”, the hinge will fail before it passes the COG. Which is why I often use two pull point, both slightly outside the intended direction of fall. If you have blocks of sufficient strength, the tractor can pull both legs. Double-whip each leg if necessary to gain enough pull. I have used a 3/4” pull line, doubled down with a 9/16” rope, then doubled down again with a 1/2” rope. It’s amazing what you can pull with that.

Also, on bad leaners, I make the back cut below the face cut so the butt can’t jump the hinge in a poor-hinge type tree.
 
15 degrees off of plumb is about the most back lean I’ve pulled, but take the fence down even chain link isn’t rocket surgery it just needs certain tools. I setup a 3:1 with the mini pulling, oak about 26” DBH 85’ got in it and set a 3/4” with wraps and half hitches. We had near ideal pull angles and a solid anchor.
 
Guesstimating the amount of pull a random tractor in a random situation is impractical.

I’ve stood a similar sized oak off a house after a storm using winch(es) and blocks. I’m going to guess the angle was beyond 45*, probably around 60*.

Make sure you have enough room to advance the equipment, stuff gets uncomfortable when you’ve backed up as far as you can and the tree hasn’t tipped yet.

The angle of the tree to the ground matters, as does the angle of the rope to the tree… the more acute the angle, the more pull is required.

A few-several hundred bucks can get you a winch that will out pull the tractor.
 
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Yea, I prefer the idea of a winch, and it's on my list somewhere down the road, but isn't something available to me now.
 
Mount it on this and you have a portable winch…

We’ve carried one across a river in a canoe, trailing a spool of rope behind us. Anchored it to a tree on an island and used it to winch over a tree next to a house on a bluff by the river.
 
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  • #9
That little loader's impressive. I wouldn't have thought it could lift it.
 
Very nice use of the root wad for stabilization/counterweight.

I wonder if you could have skipped the track loader and done it all with a rope and the excavator
 
The ex would likely not have had enough traction to get the tree up, the ex can pull with the blade anchoring it, but that wouldn’t have taken up enough to get the tree over.
 
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  • #12
Mount it on this and you have a portable winch…

We’ve carried one across a river in a canoe, trailing a spool of rope behind us. Anchored it to a tree on an island and used it to winch over a tree next to a house on a bluff by the river.
Been thinking about this. I guess you used a lead acid battery? How long will a battery last without charging?
 
We used a deep cycle battery out of my boat. Size 27 I think it is. A new battery will last for two or three pulls (depending on load and how long it has to actually run the winch). We did a job once where we had to tote the battery out of the woods every other tree to charge it for a bit at the customer’s house. Couple hundred yards across a couple of gullies/ravines. Not fun. I’ve since picked up a solar charger to help keep it going. I now keep a size 24 on hand for the winch and my little boat. Won’t last as long but it’s lighter to haul around.
 
Gas powered winch would be way better, even if it's a chainsaw winch. You just gas and go with little worry of overheating. I estimate an electric winch will only amount to a 25-70cc at best chainsaw for 20min.
 
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  • #15
Running scenarios through my head, and thinking how to set a block with a more or less lateral pull. Can a "deadeye" be made with a single line doubled over, and tied into a timber hitch? Further, would that hold well with the pull perpendicular to the stem?

Might be a stupid question. I feel like it would work, but I've never set it up in that configuration. Probably daisychain the end for a little extra insurance.
 
I’ve never seen a chainsaw winch that remotely compares to an electric winch in terms of pulling power.

He’s pulling over a single, maybe heavy, tree.

One of the strongest ways to get a pull point on a rope is to use a portawrap.

If you go the route of the winch, keep in mind the loads it can exert are way beyond most arborist rigging’s capacities z
 
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  • #19
I'm thinking 10k# is the max force my gear will take with a small safety factor. That's why I asked about the doubled line timberhitch. It gets rid of a knot(and also uses a piece of rope I don't have a lot of use for). I have deadeyes, but I don't completely trust pulling directly on the spliced eye.
 
I have a 7/8” Tenex-Tec dead eye sling that I spliced up for heavy pulls. I’ve put some heavy pulls on it over the last ten years.
 
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  • #21
@flushcut made me one out ¾" tenex(I think), and I have one I made myself from ⅝" tenex. Maybe they'd be ok. Maybe order a piece of the biggest tenex wesspur sells, and make a sling to beat the shit out of for stuff like this. That would give me an excuse to splice tenex :^D That's fun to splice, and I can do a fairly credible job with it.
 
I went with 7/8” because it will fit in my big yellow ISC block without distortion. I could get a 1” into the block, but it won’t fit without some distortion.
 
If I’m pulling hard, relative to the rope being used, I have no qualms doubling the rope in a basket configuration.

Don’t hook the cable directly to the rope, the bend radius is too tight.

If I was worried about the end line termination to the tree, I’d take a wrap then terminate with a running bowline. The tree acts like a bollard with plenty of bend radius and the bowline sees a fraction of the load.

I have 7/8” double braid for hard pulls, luckily it doesn’t come it very often.
 
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