arborworks1
ArboristSite Operative
i have toyed with using logs crossways to my drop point, they still leave small ruts. what other methods besides tires and mattresses have you all succeeded with.
causing less impact to lawns when dropping spars
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DDM
Addicted to ArboristSite
The small logs will probably embed deeply.
ask Ekka
arborworks1
ArboristSite Operative
airbag system
i have been researching truck airbags for a simple setup and break down rig to drop logs onto. i can't find any info on the shock load these bags can take. my idea was to setup two bags on each side with a u shaped braket to hold a log crossways. strap the log on and fill the bags half way for small to medium spars and full for the big uns.
i have been researching truck airbags for a simple setup and break down rig to drop logs onto. i can't find any info on the shock load these bags can take. my idea was to setup two bags on each side with a u shaped braket to hold a log crossways. strap the log on and fill the bags half way for small to medium spars and full for the big uns.
Ekka
Addicted to ArboristSite
rbtree said:ask Ekka
Foam.
Easy, light, quick and clean .... high density foam.
We lie the logs across the foam, no damage.
Keep an eye on the video section for foams, in fact, you'll see them in lots of my video's and dont even realise it. Like when you are blocking down on a slope and the logs might roll into a fence or wall ... foam it up.
i think of spars as transferring shock; perhaps spreading it out over larger area for less 'psi'. Anything springy that gives as shock absorbing; which would be dense piles of brush, foam(lighter stuff?), tires etc. Sometimes climb tree and carefully undercut large leading branch that will hit first, so now it will fold at so much force(like large leaf spring), to absorb that force; rather than be stiff and dig in.
Also, if you can guess/ calculate it right; something i call a mechanical fuse. i take 2 spars and lay pairalllell with the fall, then trestle another spar perpendicularly across. Then undercut that spar, sometimes make a small face in the top side. The idea is to get it to break, but to take a bunch of force to do so. If it takes 1000# to break that spar, that is 1000# not transferred to ground; but matched and 'dissipated' from the force formulae.
All these strategies should be applied at where the tree will hit first, perhaps in combination(s); and sometimes at the butt. Like 3' high stacks of dense brush to slow tree down, then hit spars to spread out remainging force etc.
Then, work on reducing the initial input force. Give a wide face, with no dutch, to give as long a ride on the hinge as possible/ with as little freefall as possible. Don't fall directly into the lean, where the tree has the most force and can fall more 'pointed' on leading edge of lean. Use tapered hinge and fall slightly to the side of the lean that would have less force and perhaps land on a 'flatter' face; with lean 'point' out to side.
Use a strong pull on line, but into the face, let the tapered hinge fight the lean. The hinge is a reflection of the force on it when it first folds; increase force on hinge with line, to make beefier/ stronger hinge. Favor pulling into the gunned face squarely (in good wood)to force strong hinge, then let hinge fight lean. Pulling against lean takes that much lean force off of hinge, rather than strengthening hinge. We want the hinge to fight the force like a large 'leaf spring'; so don't unload that with pull ine angle to adjust lean.
Don't pull/push or cut after after first folding; unless tree would stop folding otherwise; whereby first folding becomes an extended event, and you are 'arm wrestling tree'; muscling it down(softest fall of all). You want a strong hinge, then not weaken it with further cutting or pulling; that is a strong point of wedging, as tree lifts, wedge stops pushing! So, pulls/wedge pushes before first folding, just set up forces for first folding moment(s) to force stronger hinge. Pulls/pushes at first folding, fake the hinge out, to 'think' it has a heavier load on it, so hinge is forced stronger in response. Then, remove your artificial load of line pull; for pulls/pushes (and cuts) after when the tree will fall on own, take the same hinge mechanics/ strenghts and make it faster/weaker; rather than stronger/slower.
Especially on shallow leans; that force their own hinge weaker (because less pressure on hinge) and have farther to fall. Also, the the increase in loading in first few degrees of movemeant is much more radical on a shallow lean; worsening that problem of increased loading and suddenness of loading after first folding moment. In the 90 degree sweep from 12 o'clock vertical to 3 o'clock horizontal; 90 degrees/ 3o'clock is the most leveraged; but the increase in loading is tons more just off of vertical/12 o'clock. So much so that 50% of the maximum leverage at 90 degrees/ 3 o'clock is achieved 1/3 the way at 30 degrees/ 1 o'clock. So, shallow leans (less than 10 degrees gies hinge of 17% of potential leverage and at 30 degrees ahs 50% on it or a jump of 30+%) force a weaker hinge, but get the most intense, impacting change in loading after forming their weaker hinge, and have the furthest travel to go on that weaker hinge in falling. Conversely in tree, a near horizontal limb hinged has lots of force on it; but also forces the strongest hinge on own; and sees less change of force against that hinge strength set.
In using this Leverage of Lean Guide; the height/angle would be calculated from Center of Gravity to the compressed part of hinge(pivot).
Or, something like that
Also, if you can guess/ calculate it right; something i call a mechanical fuse. i take 2 spars and lay pairalllell with the fall, then trestle another spar perpendicularly across. Then undercut that spar, sometimes make a small face in the top side. The idea is to get it to break, but to take a bunch of force to do so. If it takes 1000# to break that spar, that is 1000# not transferred to ground; but matched and 'dissipated' from the force formulae.
All these strategies should be applied at where the tree will hit first, perhaps in combination(s); and sometimes at the butt. Like 3' high stacks of dense brush to slow tree down, then hit spars to spread out remainging force etc.
Then, work on reducing the initial input force. Give a wide face, with no dutch, to give as long a ride on the hinge as possible/ with as little freefall as possible. Don't fall directly into the lean, where the tree has the most force and can fall more 'pointed' on leading edge of lean. Use tapered hinge and fall slightly to the side of the lean that would have less force and perhaps land on a 'flatter' face; with lean 'point' out to side.
Use a strong pull on line, but into the face, let the tapered hinge fight the lean. The hinge is a reflection of the force on it when it first folds; increase force on hinge with line, to make beefier/ stronger hinge. Favor pulling into the gunned face squarely (in good wood)to force strong hinge, then let hinge fight lean. Pulling against lean takes that much lean force off of hinge, rather than strengthening hinge. We want the hinge to fight the force like a large 'leaf spring'; so don't unload that with pull ine angle to adjust lean.
Don't pull/push or cut after after first folding; unless tree would stop folding otherwise; whereby first folding becomes an extended event, and you are 'arm wrestling tree'; muscling it down(softest fall of all). You want a strong hinge, then not weaken it with further cutting or pulling; that is a strong point of wedging, as tree lifts, wedge stops pushing! So, pulls/wedge pushes before first folding, just set up forces for first folding moment(s) to force stronger hinge. Pulls/pushes at first folding, fake the hinge out, to 'think' it has a heavier load on it, so hinge is forced stronger in response. Then, remove your artificial load of line pull; for pulls/pushes (and cuts) after when the tree will fall on own, take the same hinge mechanics/ strenghts and make it faster/weaker; rather than stronger/slower.
Especially on shallow leans; that force their own hinge weaker (because less pressure on hinge) and have farther to fall. Also, the the increase in loading in first few degrees of movemeant is much more radical on a shallow lean; worsening that problem of increased loading and suddenness of loading after first folding moment. In the 90 degree sweep from 12 o'clock vertical to 3 o'clock horizontal; 90 degrees/ 3o'clock is the most leveraged; but the increase in loading is tons more just off of vertical/12 o'clock. So much so that 50% of the maximum leverage at 90 degrees/ 3 o'clock is achieved 1/3 the way at 30 degrees/ 1 o'clock. So, shallow leans (less than 10 degrees gies hinge of 17% of potential leverage and at 30 degrees ahs 50% on it or a jump of 30+%) force a weaker hinge, but get the most intense, impacting change in loading after forming their weaker hinge, and have the furthest travel to go on that weaker hinge in falling. Conversely in tree, a near horizontal limb hinged has lots of force on it; but also forces the strongest hinge on own; and sees less change of force against that hinge strength set.
In using this Leverage of Lean Guide; the height/angle would be calculated from Center of Gravity to the compressed part of hinge(pivot).
Or, something like that
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maxburton
ArboristSite Operative
I'll tell you what doesn't work: rail ties. I laid down a bunch of them under a three-foot white oak back when I was just getting started, and it didn't work out too well. One of them broke in half and the piece flew twenty feet into the air before smacking into a section of fence and knocking it down. But it was fun to watch!
okietreedude1
ArboristSite Guru
From what ive read in another thread, bags of leaves and plywood will protect a roof from 900# chunks.
Why not try that?:jester:
Why not try that?:jester:
woodchux
Addicted to ArboristSite
I wonder if truck tire inner-tubes would work .
He!! even if they pop they're cheap.
Lets go tubing
He!! even if they pop they're cheap.
Lets go tubing
antigrassguy
ArboristSite Operative
Alternomats? seem to work pretty well. We have room on the back of truck and always have 8 on hand. Suppose to be indestructible and we havent broke one, yet. And its not for lack of trying. Even in winter they seem to work well. If its going to be a large chunk we just layer them. We have the 3x8 ones and they are about 65lbs a piece. A bit pricey, but we have had em for 4 years and havent had a problem yet. As a side note you will want to watch out for warm weather, black top and the diamond side of the mats as they will leave a mark in black top.
BlueRidgeMark
Addicted to ArboristSite
rebelman said:
So, rebelman, are you speaking from personal experience? You wanna talk about it?
pbtree
Addicted to ArboristSite
I have used plywood with mixed success...
I have not tried foam, but that sounds interesting!
I have not tried foam, but that sounds interesting!
antigrassguy
ArboristSite Operative
Rebelman, they seem to be pretty darn tough. Great for driving on, dropping on and stopping stump grindings from flying everywhere. I had destroyed a few sheets of plywood in a very short time and decided to try these and have been very happy with them. Costly up front but good long term results, so far. All IMO
