Truck Pull

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MIke what if you were using a truck that puts out 7000 foot lbs with the farmer running with a chainsaw.
 
Frequently use tow lines of force on a peice, Espcialy when using the GRCS. Pull, control and many times a tie on the but allso.

When I was in KC with the storm work I wished I had 2 GRCS so we could pick from t different points instead of just taking up slack on the control line.
 
Well, I have a winch, any wenches wanna winch 'er over fer me?! If two or more reply, then the decision will be: which wench to do the winchin'!!


Or how's bout a witchy woman....



.....livin it up at the Hotel California
 
I'm getting the feeling of that unexpected breeze from these yahoo's breaking wind over their wenches or winches.Only ever had one unexpected wind come up to ruin my day. Cutting a 93' tall Aspen planted on a spoil bank. Just got a new saw and wanted to try it out. The wind had been blowing down hill all morning so I thought nothing of cutting this one clean leaving no hinge and leaving it stand while I stopped for lunch. I was just starting on my second sandwich when the wind changed direction and that tree took off up the hill and took out over 30' feet of cyclone fence and downed 800' of power line. On my property and I own the wire and the poles. Never again cut a tree clean and leave it stand. Cost for that stupid trick.$1,000 to have the wire restrung. $250 to have the electric co. come turn the power again.$300 to fix the fence and I will not live down the embarressment of my stupidity not to look out for safety first. The saw worked great though. If only I had tied the tree off.

On using the block and tackle, I was about to let a new guy either prove he could cut a tree down or not. Got out 125' rope block and tied it into a 75' apple tree in very bad shape at his mom's place. Landing zone clear for 90' in all directions.Now he has to prove he can fall this tree were he says it will land. His nephews ages 5-7 are pulling on the tailine well clear of the the tree and I tell them don't pull till he starts to cut the tree. He is facing away from the tree to start the saw and as the saw rev's up the kids pull on the rope. He turns toward the tree as he picks up the saw and tree tree snapped and fell before the saw got close to the tree. We had a good laugh about that one, the kids pulled the tree down before he got to use the saw. The kids ran around the rest of the day thinking they were super hero's because they could pull down a tree.
 
Murph attempted refute

1. A truck's pulling power cannot be quantitatively measured by the operator without a gauge on the rope.
ANS: Can any pulling power be quantitatively measured with out a gauge on the rope?

2. Using a technique intended to work as a back-up in case of the top breaking would create slack in the rope which the truck would quickly take up and shock.
ANS: This asumes that the truck is pulling 'at speed' mostly U would pull gently using 'torque'.

3. Hinges are not designed to travel a great distance. The wood has been there for potentially hundreds of years, it could crush the side of the hinge closest to the notch, it could break on the side of the backcut - especially if it is thick or "meaty," and it could snap off completely if it moves too far (picture breaking a stick over your leg).
ANS: Surely this depends on the tree species and the type off fibre layed down . I my expierience organic celluose constructions can be flexed to a point. Also the design off the falling notches( cuts) can assit this flexing.

4. A sawyer should be able to fell a tree without a rope, if not, rigging is necessary until the tree is of a size that it can be dropped from the ground.
ANS:This is simply not true!!

5. A rope must never be placed under a circumstance in which the wear or stress cannot be quantitatively measured.
ANS: Wear and stress measurements in the field are mostly approximate estimates off loads over time backed up with visual inspections. Is that quantitative measurement?

6. No action should ever be taken where the rope could break.
ANS: Agreed!!

7. An otherwise healthy root system may fail if such force is applied.
ANS:This could apply to any winching system.

8. If the top were to break, an equal and opposite reaction would take place, sending it in the opposition direction of fall.
ANS:Sounds logical but is really a simplistic pseudo scientific description of 'a possible outcome' in the event of failure.

9. The truck could stall or suddenly move forward and no longer be the tool that is so heavily relied upon.
ANS:Operator error or mechanical failure possibilities exist wherever tools are used.

10. Routing a rope through multiple devices increases friction and points of failure.Ans Srry ran out off room!!
 
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I'm not sure if the attachment will make it through (first try at one).
I think there's a difference between running a tag line all the way up the back side of the spar, then over the top, and tying the running bowline on the backside near the top, and then over. It seems to me the the first scenario uses a greater part of the tension force to jam the tree straight down into the ground. This is what Mike is referring to in his vector diagram. But when the rope is tied up high, is this jamming-down effect the same?
 
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Always leave a hinge, it helps control the fall of the tree.
Wedges and felling bars can be used and many arborists don`t bother using them for some reason.
 
Would gently taking the slack out of a line, then pulling 4 foot forward on a 7% stretch line that is 120' long qualify as judicious pulling, ie. relatively safely gauging? Or 2-4 wraps on a PortaWrap, and pull till a man can't fight the slip so as to gauge? Or experienced eyes and feel, observance of all that and tree top?

i think the higher the leverage without breaking is best, snaking down the back allows this more times than bowline tecqunique. i might opt for a bowline pull on a well split fork at the top in some cases to get a straight/high leverage pull, calculating the approximate strength at the fork below, rather than the higher hitch points.

You could break a top out with either method, but snaking down the back allows self adjustment to some extent, for the flexing top would bend out of the way and the pull would come to further/stronger down if it persisted. On a bowline pull, the continuing pull would remain at the same point; which would be more risky. i Love self adjusting effects in machinery!

i think that in addition to that self adjustment, stronger, more centered connection of snaking the line down the back, and the easier release after felling by cutter (as JP reminded), that there is something else here. i don't know how to prove it, but i think that bend in the line wants to come out at the top, it wants to be straight, the more pressure that is applied; i think that helps the felling some how. Kinda like i see the clove at the base being pulled, and the bend at the top, pushing the top forward (with leverage?). This is how i came up with the self torquing rig in climbing actually, another crossover lesson! Also, as i witness it, all that is compounded by the line being in more of a cocked back position. Is that what you mean Mr. F.Berkel on vector study?; Whereby the closer you are to the tree, the more cocked back angle?

Always leave a free flowing (un-obstructed/cleaned face, allowing the machine to work smoothly), no crossed cuts (that doesn't perform some specific purpose, or isn't neutralized somehow) in sound wood. The reason for maximizing the leverage and pull here was to pull the tree forward into the face with more hinging wood, delivering into a wider face; both to lend greater control (speed / direction). We also pound wedges from behind to lift the tree into the face, as line is pulling top into the face. Then allow it to commit, then let the machine of the hinge gracefully usher down the leveraged mass; i get excited just thinking about all that power strategically controlled like a ballet of slow motion and flowing power!

Very good Murph! Still think that center punching the older stiffer fibre out of hinge can allow more flexible, younger fibres to do this mechanix of hinging more positively. Also gives a nice gunsight for real critical lays, if it passes all the way thru to the back. Though this eliminates the fibre across face, so shouldn't be done so much in weaker, decayed varieties. Theoretically (i think) the tree will fold with about the same amount of fibres, per leveraged pull, they are just rearranged, this means that to replace the fibre across face, they are deeper in, requiring more flexing, bending over than front fibers. ie. flexxing them more as they bend over the front fibres, so should be really sound/flexible fibre for this trick. We practice on easy pines.

With, or without an input force of a truck, these methods are to maximize the leverage, security and hinging of these machine parts.

The tree will give at the weakest point/ per leverage applied, whereby the root system gets more leveraged pull than the hinge, so you make the hinge the weaker point, to give first, per its leveraged pull at that point. So weaker rooting would get a thinner hinge, so that this mechanical fuse (thinner hinge) is scheduled to give out first, saving the root system .

There is another warning with root systems, dropping with more hinge control on speed, puts more pull on anchor (stump)during this part of the motion. For the stump is the anchor for this braking force, that controls the speed. Whereby; even a good anchor/ stump can shift slightly unseen underground, and bust entwined in its roots: wires & pipes if wrapped real tightly. All my liability insurance i've carried (luckily not used), doesn't cover underground damage. And that folds back into climbing, for if you use this extreme hinging on a preservation job(non-removal); you should do it leaving a longer stob, so the deeper fracturing of fibres doesn't run into the parent connection, from the stress of using the hinge more.

We use 4" blocks and 90 degree turns for our redirects in this, except for returning to load to com-pound pulling force on the load. We use hitching and anchoring at these points that are stronger than the line, and don't pull very far. With that, i believe the heat/stress factors of simple redirecting are neutralized. When compounding force, the redirects on anchors and loads are at 180 of course, but then with truck as input pulling force, that too is generous overkill, so barely really pull!

Maximize: Leverage, security and strength; then apply necessary pull to gently usher natural force (falling after commitment) at the right time...............
 
Spidy,
Thanks for sharing your thoughts. Agree or not with your points, it takes a generous heart to take the time and energy to verbalise some fairly compliated thinking, as you have. It's been a great thread for all.
Keep drivin' safely! And thanks again.
Your brother in service,
Daniel
 
Treespyder, Thanks for another thoughtful/technical post. Just thought that I would share some technical data on bending wood. I too sometimes cut out the center of the hinge leaving wood on the edges. In some cases this is the best way to promote a controlled fall. However, the ratio of wood fiber is not one to one as you alluded to. If a given piece of wood requires X ammount of force to bend making the wood twice as wide will double the resistnce to bending. If the wood is made twice as THICK the resistance to bending increases 8 times. Center punching a hinge doesn't let us make our hinges a great deal thicker but it still is a useful technique for maintaining a balanced hinge and controlling the fall.:cool:
 
How did you come up with the theory that the older the wood is, the less suitable it is for hinge wood?
It is my understanding that heartwood is actually stronger and more flexable.

The shape of the hinge, in my opinion, will be stronger if it is one long thin strip across the stump, rather than a square area on each side of the stump.

Punching out the center of the hinge is a great way to stop the log from getting wrecked at the end, but it is definately not stronger, IMO.

When you pull with your truck, what size rope are you using?
Are you applying the presure on the rope before, during, or after the cutting?
Do you pull witht the truck forward or in reverse?
What is the specific advantage of the truck pull vs. commonly accepted methods?
 
Spider:
Just seems to me that the tension force is coming from a direction closer to that from which you're pulling, when the line is tied near the top. Can't prove it.
I've used the truck pull (always backing up, to maintain visual, low target risk, sound appearing wood) on very rare occasions, usually late in the day, trying to get done. This may well show bad judgement, like choosing to drop rather than lower a branch that one time out of a hundred might strike the porcelein donkey ornament, but in a weaker moment...
 
Oh, yeah, the part about bending the top: I understand what you're getting at, but how much are you actually bending, say, a two foot diameter top of a twenty foot tall spar? Or even a thirty foot? If you're going to such overwhelming force to insure that your (extra thick) hinge works, I think you do run the risk of eventually uprooting a tree, which could cause it to come down in the wrong direction.
Appreciate the thought you've put into the subject.
 
Thanx a lot guys; but truly i enjoy the combined brainstorming of all, taking in other's experiences and testing them against my own. Specifically for me, that draws out these things that i have pounded deep, folding over on themselves; never quite assembling like this..........

"There is nothing to writing. All you do is sit down at a typewriter and open a vein." - Red Smith ;)

Though there wood be some reduction in the fibre count in a center punch (or holding wood 'triangle' for supporting side leaner's pull to the opposite side on the hinge's axis), as rear most fibres where worked more flexing over frontmost. But, i'm not sure that it would be 8/1; not sure if that is what is being stated Stumper Man. But, in consideration of both topics, i have found that a center punch seems to reduce the amount of holding wood control on some side leaners. It seems that the center 'post' you are punching out is needed to leverage that control of the holding wood to the lean on the same axis to the opposite side or something. Just thought i should toss that warning in...........

i think that the question of flexibility of inside fibers of hinge is going to be (like a lot of things) situation dependant. i was taught that 'real' heartwood was stronger, but i think that it is less flexible in trade. i kinda look for dryness of facial portions, imagining that the 'livelier' wood is more flexible. Sometimes the center looks kinda dryer to me, i imagine this is like 'bonier'- stronger - but less flexible as i come up with a strategy; inspecting the clean face cut.

When using more controlled hinging, that depends on the flexiblity of the fibers to a max, this centerpunching can help in good wood. Of course, all this only makes maximum, witnessable sense delivering into a wide face, that would mechanically allow and test those flexing fibers. For by a wide facecut commanding that the flexxing fibres are not outrightly sheared free by the immense mass, momentum and leverage at the hinge slamming and closing early, then the flexxing fibers can work their magic through a wider arc.

i had some pines whisper me a lessoon that helped instill this about younger wood; a number of times; i had a pine swivel sideways somewhat. When i inspected stump for lessons on next cut (always do that, even in tree!), i would find a leathery stripe of bark line holding on one side and not the other, off balancing the pull right at the end. So, even there it seemed that the younger wood was more flexible. So now after cutting wide face; i circle the back of the tree, hinge corner to hinge corner. This eliminates this leathery stripe from developing,as i cut deeper than its incursion, but it also tests the straightness of the hinge & sawcut, tests the track for topical metal, and lays an even trail for the finishing cut. On that cut, i have more speed control, as i can go faster with that wood gone, as in center punching to back. i can always back off the gas to slow down, this just gives me more 'high' end.

Times that you rely on more fiber flexing for a given size and weight of tree is when it is leaning favorably 20 degrees rather than straight up. Where as the leaner is feeding into the pull of that jealous witch gravity, and will come over with a thicker hinge,as it could express it's weight and leverage in that direction earlier in backcut. Or when you use high leverage and pull to imatate that extra pull and move spar forward with the same amount of hinge as leaner. Or even lifting with wedge etc. into the face.

All this is to bring down things more controlled and gentler. Reducing damage, sprung over limbs, buried limbs, climbing, time etc. Like calculating one surgical motion that can take the place of many more assembled ones of varying risk. Also for fighting some backlean circumstances by shifitng the balance into the face confidentally. It also can deliver a lot of brush at the road nicely as you schedule that to happen with bigger pull downs through better control!

Gotta get more ink....................
 
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As far as the relationship between the strength of wood and it's age, type (sap/heartwood), and location, it all seems like speculation. Anyone know something solid about this? I'll try asking around....

Nickrosis
 

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