Advanced Rigging Walking Brush and Wood

[(WLL)]

we call this butt hitiching

we use a spider legg n a tag line but we usualy tip tie with 1 rope and with 2nd rope we walf hitch the butt/butt hitch the butt it takes 2groudies 1 climber. a grcs is allways nice 2 have but most companys dont have or feel the dont need. quality never costs as much as it saves.

 

[tam]

hey jomoco, thanx for that real good explanation! i've never heard about that b4. i thought wood walking just meant zip-lining.

 

[Kneejerk Bombas]

Like this?

 

[(WLL)]

looks like #2 is extra

 

[jomoco]

A word of caution about walking wood

looks like #2 is extra

Mike's illustration is right on the money for the simple reason that by putting huge lateral stress on the lowering points, it would be very easy to exceed their weight or lateral stress baring abilities, this would result in catastrophic failure at one or more lowering points, this should be avoided obviously at all costs.

Only use lowering points that are strong enough and preferably relieved of their original load, so they can withstand both the vertical and lateral stress that will be put on them during this process. If the lateral distance to be traveled is great, 2, 3 or perhaps even 4 lowering points may be required depending on distance to be traveled or the weight baring ability of the lowering points.

This is an advanced rigging technique that needs to be well understood before attempting to use it, there are so many variables involved that it should only be employed by a climber that thoroughly understands the forces involved, and has communicated them to his ropemen so they understand as well.

Thanks for the excellent illustration Mike, a good illustration can sometimes convey more than a chapter of words.

Work Safe

jomoco

 

[(WLL)]

over kill or very riskey??

looks in-practical 2 me. any large wood should be blocked down and moved in 1 way or another to its destination if not Ur just lookin 4 problems. lets keep it practical n simple. showoff/stunt-men dont get very far in this line of work.

 

[jomoco]

looks in-practical 2 me. any large wood should be blocked down and moved in 1 way or another to its destination if not Ur just lookin 4 problems. lets keep it practical n simple. showoff/stunt-men dont get very far in this line of work.

Either you don't have enough experience to have encountered the many situations that demand wood walking, or you've had an extremely superficial exposure to professional commercial and residential tree service to make such green observations and express them in a professional forum.

I hope you make an effort to educate yourself soon before you make such brash and insulting observations to people trying to help spread a little professionalism to beginners and those willing to learn.

jomoco

 

[jefflovstrom]

I like this thread! Mike's grahic was cool. Draw in a "figure '8' on a big sling at the butt to slow the swing. When you guys think this is over-kill, Think that it was also bid in with the man hours.
Jeff Lovstrom

 

[woodchux]

That is a pretty advanced rigging technique. The simple drift lines i was referring to would only use 2 lowering points, and maybe a tag line.

 

[ddhlakebound]

This is an advanced rigging technique that needs to be well understood before attempting to use it, there are so many variables involved that it should only be employed by a climber that thoroughly understands the forces involved, and has communicated them to his ropemen so they understand as well.


jomoco

Thanks, jomoco. Great thread. Threads like this are why I spend time every day reading here.

Now, would you be so kind as to go into more depth about the variables and forces created, so when I (and others) encounter situations where this technique may help get the job done, that we have a greater understanding of the physics involved? Especially involving lateral forces...

Thanks. ddh

 

[clearance]

Pretty cool indeed, thanks Jo and Mike, now I get it. Like anything I can see the need not to go too big. Interesting, most of the trees I cut down are conifers, so something I might not use but good to know and understand. WLL, if you have been here for a while you will know I can't stand the show off, look at me!, look at me! stuff some arborists brag about, this is different.

 

[beowulf343]

Jomoco-good thread!
Mike-a picture really is worth a thousand words!
This is a handy setup but unfortunately, you can rarely set it up so perfectly horizontal. In fact about the only time I was able to set it up so straight was on a bunch of oaks I took down in Rochester that had huge limbs that hung out 20-30 feet from the trunk. I'm more often in silver maples and willows and tend to use a similar setup only a bit more vertical. Now you guys know that silvers and willows tend to grow up then split into several large leads. When I started doing takedowns, I'd just rope one lead into another crashing them together. However, this is rough on equipment and often if one lead is over a house, you can't get the branches you're taking down far enough into the next lead to clear the house. Fortunately, several years ago, I saw a climber use the "wood walking" system. (Around here, we call it the silver rigging.) I'll set a block high in a central lead then one or two more blocks lower in adjacent leads running toward the side my landing zone is on. Simply cut the branches and walk them from lead to lead until you're over your drop zone. Then when chunking down the lead, I'll run a false crotch and drop my chunks onto the stem. My second high block will be attached to the grcs. Cut the chunk, drop it gently onto the first block with the second one holding alot of the weight. Then simply pull it over to the third block then the fourth one, etc. This system works even better than a speed line because you have more control of the chunk and you can take much bigger pieces.
Similar to the picture only my blocks run low, high, low, and lower.

 

[John Paul Sanborn]

Either you don't have enough experience to have encountered the many situations that demand wood walking, or you've had an extremely superficial exposure to professional commercial and residential tree service to make such green observations and express them in a professional forum.

I hope you make an effort to educate yourself soon before you make such brash and insulting observations to people trying to help spread a little professionalism to beginners and those willing to learn.

jomoco

Well put, not an invitation to flame back. The lad is only 26.

Now, would you be so kind as to go into more depth about the variables and forces created,

Force increases with angle of inflection, th closer to perpendicular you get the higer the force. Who has the table from "On Rope" handy?

why two per lowering device?

The hobbs requires one tailer and one cranker, where the GRCS is self tailing on all but the heaviest loads.

 

[appalachianarbo]

I don't have the table on hand, but when the angle between anchor points is 45 degrees, both anchors equally share the load. As that angle increases to 180 degrees, each anchor point is supporting all of the load. So, that 2nd pulley in Mike's drawing is critical (depending on the weight of the load and the stoutness of your anchors) in that it reduces the angle between the anchors, therefore reducing the load that each anchor must support. I'll see if I can find the exact figures...

 

[jomoco]

Thanks you guys for your help in explaining the basic principles involved in walking wood and brush, it was quite accurate.

I had a long day today cutting down Australian weeds (Eucs) at MCAS San Diego today, and talking with a few of our brave Marines on the base, I envy them up there kicking in their afterburners and having a good time.

I just want to caution those who try wood walking for the first time to do it in a non critical situation, and to start with light loads until they develope a feel for the process, and then progress to heavier loads in bigger wood with stronger lowering points.

You'll find that either a Hobbs or a GRCS is required for heavy loads, two of them for seriously heavy loads, and pulleys at each lowering point of course.

I find that when using more than two lowering points a porta wrap and sling works fine for the the first lowering point because it doesn't have to do any lifting, just precisely controlled lowering, it's the number 2 and 3 lowering points that have to achieve mechanically advantaged lift.

I'm unfamiliar with the GRCS device, but it seems to have many advantages over the Hobbs devices that I use to walk big wood with.

Just start slow and easy and progress with common sense, and I guarantee that your customers will be properly impressed with your rigging knowledge.

Work Safe

jomoco

 

[John Paul Sanborn]

I just want to caution those who try wood walking for the first time to do it in a non critical situation, and to start with light loads until they develope a feel for the process, and then progress to heavier loads in bigger wood with stronger lowering points.

Jo, do you back up your rigging points when they ar far out on a limb? E.G. guy the limb back up into other limbs?

 

[jmack]

Drift lines

ayuh.

 

[jmack]

I'm a little curious as to how one ground man could possibly lower one line and achieve any lift at all with the other, particularly if the wood or brush weighed more than he did?

It's the mechanical advantage afforded by a hobbs device that makes them indispensible for walking 500lb pieces of wood sideways over long distances, this has allowed four rope men and I to do what we've done safely. One rope man keeps tension on the rope, while the other rope man uses the turning bar to turn the capstan to achieve lift.

Maybe what you call a drift line is not at all what I'm refering to as wood walking. I am quite sure that what I've described would be impossible to achieve with just one rope man.

jomoco

for my spped line tree question we use the weight of the wood and a tree out by the street and drifted with a porty and da weight of the log

 

[jomoco]

Jo, do you back up your rigging points when they ar far out on a limb? E.G. guy the limb back up into other limbs?

Yes John, Many times, and well worth the time and effort not to mention peace of mind.

Excellent point, thanks.

jomoco

 

[John Paul Sanborn]

For smaller loads you can put the rig point in a retrievable fashion and let it outonce the load is near vertical.

The load line runs up through what starts as a redirct, once the load is cut free the rigging anchor line is let out to become the drift line.

Sometimes the ground needs to keep crankin on it so the load does not lower too far, sometimes the drift line needs to be let uot just enough to clear the obstical.