Stacking wedges

[murphy4trees]

I usually use a high pull line to get a tree moving into the face, and rarely use wedges to assist the process.... I've heard that stacking wedges is surprisingly effective and I think Arbormaster may teach the technique..
I like my pull lines and will set up multiple lines on a heavy backleaner... But I'd still like to try stacking some wedges... So any tips or suggestions from you logger types???
I have a backleaning oak to get down if I get the contract...

 

[TheTreeSpyder]

i've tried it, more comfy with rope.

Not big time Gypo, Burnham, RB etc. prolly could answer better;

But i make 1 observation here: It is easier to keep pulling on line after movement starts, using a wedge(s); any movement releives the pressure.

i think that the line continuing to pull after movement starts can weaken the hinge, assuming the tree doesn't just stall, and must be urged more. i think that maximum hinge strength is at first movement, pushes/pulls after that besides tree lean in it's own self adjsuting cycle, pitted against itself pushes and pulls added by us bend more fibers, that the tree should be bending.

If you want to force a stronger hinge, catch it right before folding and load higher push/pull to target to fake out Nature, and make Her prep for a higher load, then at bending as She takes on the load, remove your faked part. Thus, forcing a hinge stronger to handle your increased force, then sneak and remove it.

The lifting off, stopping of wedge push is automatic, upon movement. An elastic line can store energy and keep on pulling more, or be pulled more.

Another way the hinge can be weakened is by cutting too fast, this sets the time element for the power put on the hinge machine to be slow powerful or fast weak; from the same power sources of lean, line and wedge.

i think that a deeper face brings the pivot closer to the backlean, taking away some of the load you fight. Once again drawing lean from C.o.B. to the pivot part of hinge (compressed fiber patch under lean side), to judge that the moving back of the hinge is proper. But, at the same time, in lifting from the rear with wedge; i think a deeper face brings the hinge patch closer to the wedge leverage to use for adjustment; i beleive this catch 22 lessens the leverage of the wedge, for it isn't as far from the pivot now!!

I like over the top lacing, and not high, brought low; imagining the tight line running down the backside pulls more focused forward(?), bracing/stabilizing(?). Also takes whatever power created and applys it in such a fashin on the spar as to induce a more pro-nounced arc-ing on the hinge(?). This also give cutter less to do, around that backleaner, safer(?)

So my preferance is a deeper face, with the line used carefully, laced over top; wedges maybe for some help, initial lift, dog positively any distance gained etc.

Orrrrrrrrr something like that.
:alien:

 

[Stumper]

Wedges are useful and stacking them does allow for more movement "overcenter" but I love lines set high. Even a line set midway up a tree will beat stacked wedges. Reason number one is the length of the lever provided by the spar will outwork the reltively short inclined planes of a wedge. More signifcantly for us working around expensive "targets" is that stacked wedges try to do all the work inches from the hinge-if the input forces at the wedges OR additional forces up the lever of the spar (such as a wind gust ) cause the hinge to fail prematurely things can go horribly wrong. A strong line up high is positioned to counteract 'surprise' forces better without inducing additional stress at the hinge in undesirable directions.

Pacific NW loggers have done amazing things jacking trees (which is big step beyond stacked wedges) but even though a lot of money is on the line if they bust the log by dropping it the wrong way or something it is still only "potential money" when they screw up nobody loses what they already had (provided noone is actually hurt). Stick a nice house in the drop zone and it changes the dynamics of the situation. 'Pretty sure' and 'most likely will drop perfect' aren't good enough.:angel:

 

[MasterBlaster]

Wedges are GREAT for ALAPing stumps and bucking big wood.

I set a line to pull a tree.

 

[John Ellison]

I wedge trees if needed in the woods, but if around something I set a pull line unless its a slam dunk. I always carry a couple of wedges in my back pockets when I'm cutting so there handy and I will use them with the pull line too if its a "tuff one".
If your stacking wedges, then your moving the tree a long ways. Lots of work. Normal wedges will tend to fly out if you stack them, sometimes a bit of sawdust under and over will help them stay in. Dont wedge at face level without full face protection. They sell special wedges for stacking that work real well, there are aligning grooves on them.
I'm sure most of you probably know but, always cut the bark off the backcut where the wedges go in, always use two (or more) wedges and alternate whacking them, dont get in a real big hurry or you will be wasting energy. It takes a good second or so after you hit for the top of the tree to move all the way.

John

 

[NeTree]

I prefer to use pull lines, but will sometimes add a couple wedges just for extra force and safety on a heavy leaner.

Be careful you don't go too heavy with the wedges... it's real easy to pop an already stressed hinge.

The key benefit from stacking wedges is as a precaution if, say, part of the rigging breaks and the tree tries to sit back into position. By keeping the wedges in slightly tight, you leave no room for the tree to gather energy as it tries to settle back. Otherwise, it could very easily gain speed and energy if allowed much movement, and pop the hinge when it gets to that nice sudden stop your backcut kerf will give it.

 

[Ryan Willock]

If you're going to use wedges then the ONLY ones to use are the K&H Red Heads with the 10'' triple taper. You would be AMAZED at what you can wedge over if you know what you are doing! If I have some with really bad back lean or they are leaning toward a road or power line then I back the skidder up to them, climb up on the log arch and set a choker about 12' in the tree then drive out and tighten up on the line make my face cut, tighten the line a little more then make my back cut and over she goes!

 

[TheTreeSpyder]

i go for lines too, but think there is stuff for us to learn/appreciate about wedges. i agree with Stumper's leverage analysis, NE safety wedge concept.

i think a wedge gives Speed X Hammer X Ramp x Distance to hinge. Another multipler is the arch on the hinge itself the other forces impose. So the backcut must be flat,so wedge pushes up to tip C.o.B. forward. If a downslanted backcut (which some do agianst it going the wrong way, but slanted is weaker anyway) is wedged, the wedge pushes more directly forward where it is sending the C.o.B. So it would do that faster, but with less power, arching on the hinge would push forward less directly, slower, compacting it's power into a smaller distance of movement returned. A similar analysis for over the top lacing to give more arc pressure, than straight forward pull, especially more noticieable as the line angle is more perpendicular to the spar; but i think that quanity always existing. When you can send the same force through a leverage multiplier(instead of apllying direct/fast pull/push); i think you should!

The rope over the top, give stronger mount for higher trusted leverage positioning i believe. On leveraging the sidelean axis of the hinge load, i go to lean side with the pull line, then down, to apply more pull to the leanside, to pull it more forward to target. Or, down around backside tie low to the control/light side to give a kinda torqued pull (tourqued/arched pull on spar; that tries to pull around, only pulls forward, placing more movement applied than recieved..). On a balanced tree, one can go to the side as only tie mount, and think pulling from a crossed angle doesn't make any differance; and be wrong; so this as all can work for or against you; as an existing force to be called either way. Don't run the line from pull position to the light side, for this would serve to feed towards the already heavy side.


i think that the higher line is more leverage, as farther pull from hinge, more control over the C.o.B. But, i think another elemeant i have noticed to that is that, the line should go above the C.o.B. i think that you can develop higher pull to go to the lower position and have the same leverage force. But, i think there is an elusive lil'deal of the pull coming from where it is pinched between the C.o.B. and the hinge, that it is different to be over the C.o.B. and leverage is not the whole story, of what ya can get out productivity/safety wise in height of rope mount. If someone pulls you forward from under your army pits with the same line, you would fall forward, right at C.o.B. pull straight forward, at ankles/ even knees(below your C.o.B.) you sit backwards(?)

If that was a top; being pulled from below the C.o.B., could come more straight down crush climber i always thought (that is where i dreamed up that one, up in thin air; in position of stress behind shallow backleaning /balanced/ shallow leaners etc. and how i played it and figured it would go under same principals on ground.

So, anyway, i think a tall tree logger especially is gonna go fer the lil wedges; as far as compactness, and mebbe not to good at getting up in what would be the safe range. i'd imagine their prejudice against rope pull when some greenie tried to set line is due to some of these factors. Also in the shallow leans of the sardined skyscrapers, the degree of loading per movement is most intense, right off balanced vertical, and after inciting movement wedges do 'back off' their pressure as tree moves, serving to theory i previously posted.


Or something like that
:alien:

 

[Nickrosis]

Originally posted by John Ellison
Normal wedges will tend to fly out if you stack them, sometimes a bit of sawdust under and over will help them stay in. Dont wedge at face level without full face protection. They sell special wedges for stacking that work real well, there are aligning grooves on them.

Good advice. I don't know about the sawdust...I'll have to try it.

Stacking wedges is nice, but you should pop them in and hammer from a safe distance. Last time I did, I had a face shield on. It basically gives you the benefit of having a much larger wedge. If you have a bigger wedge, that'd be great, but you're often working in a situation where you have a wedge in and you need to make it "grow" by adding another wedge.

You can do a lot of with wedges! If you can wedge without a pull line, you can save time and make money if it means you don't have to climb. For a spar, I don't think it's worth NOT having a pull line because it's so easy to install while you're up there.

 

[NeTree]

They do make wedges meant for stacking. They have "keys" that mate them together when stacked. Check around.

 

[a_lopa]

i always carry three stihl wedges, if some thing has a back lean and i think ill get it over centre il quater cut it slam a wedge in bore cut it wedge, and do the other quater and hit the wedges alternate only on decent diameter of course the trick is to not lose your nerve and cut out enough wood for it to work you need to get the wedges inside,make the bore to hold the tree from sideways movement when bringing over

 

[Husky372]

if you dont have enough wedge what you can do is make cookies to raise hieght of your wedge. you can make them as thick or thin as you need.

 

[TheTreeSpyder]

Now their is a good common sense tip!

Here is a drawing i made a while back warning about a slanted backcut, and then with wedge use.

How, if one uses this to feel better about not sitting back, the slant is weaker.

Also, in this theory; the leveraged force of the wedge action is lessened IMLHO.

Mostly, i present it here for it's examination of the forces at play; how the wedge applies the force of the ramp being slammed in is also important; and how far back from the compressed pivot are of the hinge; is also a leveraging factor.

As a safety backup, even helping puller, force is force; then release slowly with the extra force loading the hingem aking it prep itself for a bigger load; force it stronger, i think.

Or something like that.........
:alien:

 

[Kneejerk Bombas]

You all know this, but nobody mentioned it it so... wedges work very well on some speices of tree, like Spruce, and work poorly on others, like willow.

 

[NeTree]

Glad you brought that up, Mike.

Pay attention to the tensile strength of the tree you're hammering wedges into.

 

[Burnham]

Some good advice has been offered up so far...I'll throw in my thoughts, some of which will be a bit of a repeat, some will perhaps be counter to others. I should add that I generally am talking about falling bigger timber here. Last week I took down 4 dead hazard trees; old growth Doug firs in a camp ground. The smallest was 42 in. dbh, the largest 51 in. dbh. Heights around 225 feet. There where two of these that I felled against their lean, one directly against. Two sets of a stack of two 10 in. wedges did the trick...and that was some really heavy lifting. Targets all around, too, though not as costly as someones' house . I was able to place one of these between a $12,000 vault toilet and a pair of expensive interpretive signboards...32 feet between the targets 100 feet away from the stump...perfect strike down the middle...whew.

I agree that the hard head wedges, a plastic wedge with a steel insert in the head, are a nice item for hard driving. Even better are magnesium wedges, which drive stronger, slip not at all, and won't destroy chain when the eventual inevitable touch occurs. I use plastics mostly, and add the mags if things get tough. When a plastic quits driving a mag will still stand the tree up. Probably 80% of the time I only use the plastics...the mags come out for the hard jobs. The truth of the matter is that much of the time stacking is not needed...usually single heigth wedges does the trick.

I have found that the sets of plastic wedges with the slot/ridge arrangement will spit out almost as readily as standard ones. Saw chips in between plastic wedges can help, but nothing beats mags. They stack with a plastic without either one spitting out, too.

As others have noted, any heavy lifting is best accomplished by alternately driving a pair, trio, or four wedges spaced along the backcut. Don't play around with some weinie driving tool either, use a real falling axe with a 5 lb. head securely hung on a sturdy ash handle. Remember to always keep an eye out overhead while driving to watch for anything you might dislodge with the vibrations driving wedges generates.

I actually love the act of wedging over a tree...get the wedges in and snug as the backcut deepens, keep them tight to prevent a setback, finish the backcut off to leave exactly the hingewood you want, pull the saw and stash it away safe, and drive that big puppy over. Everything happens slowly and in control. The lifting power in those little wedges is awesome.

 

[NeTree]

Only other thing that comes to mind to add is to use enough wedges across the width. Don't try to wedge a 3' tree over with just one (single or stacked). Place a series across the backcut. Each single/stack will drive easier if theres others closeby. Few hits on one, then the next, etc.

 

[TheTreeSpyder]

Walking it up is what i think of it as.

If the hinge is strongly to be leveraged, i push straight to use the leveraging, If hinge is less trusty, i will use wedge direction to counter lean directly, not going through the hinge with that part of the load that wedgfe lifts. If i have a 3rd wedge on something big; i only pound the control side wedge in deep enuff to hold the walking up, not as a leading lift to push into the sidelean.

Burnham that was great and a view of wedge uses i don't think we see; and one of the best uses for this thread i think; there has got to be an art to it, that we could use from time to time.

With a tree that size,it would take a lot of line (throw and pull)etc., manpower in the way of danger, and very far back for easy communication. Might have to look into mag wedge thanx.

i think that your close is one of the most important points, build up power in hinge; and schedule that power to go slow/powerful, instead of fast weak garnered from the lean force running through the hinge. Gypo says tickle the fibres away one by one i think; i've thought of it as breaking guitar strings from MB's guitar, releiveing them one by one of the load, until the spar starts to 'breathe'/move. Or walking to a point of failure, and softly letting it tip on it's own. Pulling on a line now at this point i think invites fast/weak , unless at full stall. So, with a wedge as the tree lifts, the machine automaticallly releives the pressure added, allowing a slower fall.

Or something like that
:alien:

 

[NeTree]

Spidey hit on a mistake I see all too common.

Don't just start pounding away incessently.

Give the top of the tree a chance to "catch up"- especially if it's in full foliage (added wind resistance and weight). On a 90'+ tree, just 1/16" of lift at the kerf will equal several feet of movement at the top.
My usual practice on the tall ones is to allow 3 seconds in between wedge strikes to give the top a chance to move in the desired direction.

On shorter trees, you can go a little faster.

Working with another company from AS wednesday, we pulled over a 50'+ red oak, with roughly 15 degrees of lean to it using the come-along and stacked wedges, working one-click at a time to allow time for the top to move.

The top moved 20 feet +/- before reaching over-center; the kerf only opened up about 2-1/2".

I made a conventional notch, and then backcut to leave 2-1/2" of hinge. Once the tree hit "balance" (as evidenced by the force required to work the come-along, I zipped the hinge down to an inch, and let the force pent up in the stretched rope do the rest.

 

[Burnham]

Erik is right about swinging slow and steady...I didn't think to mention that, maybe 'cause my old body would complain mightily if I went to whaling away with that 5 lb. axe any faster than that . Five minutes of steady wedging will have me huffing and puffing...if you have a partner, stand one on each side and hit alternately on the alternate wedges; as Kenny says, walk it up.