Unlevel face cuts

[Kevin]

What happens when you make an unlevel face cut ?

[Reddog]

Well, is the back cut going just as bad the other way?

[Kevin]

The back cut will line up with the face cut.

[Radar67]

I would think it would want to roll to the right (as you look at your diagram).

[Kevin]

Why would that would happen?

[Reddog]

The back cut will line up with the face cut.

If they line up, it will fall were the face/hinge is aimed.

[Kevin]

What's happening to the hinge as the tree comes over?

[Radar67]

My thinking is the hinge would have more tension building up on the left as the tree comes over. At some point that tension would snap on the left of the diagram and cause the tree to sort of roll to the right.

[Kevin]

 

Right on!
The notch closes first on the high side breaking the hinge wood on that side first causing the tree to roll out.

[Kevin]

Reddog;
You are correct in assuming the tree should fall to the gun but because the face goes into a pinch on one side before the other the outcome is different.

[blaze83]

I agree, however if the hing held untill the tree was fairly well into its falling path would the tree begin falling out of gun in proportion to the angle of the face cut. I would think even with the angle, the hinge would at least begin to break along the entire length untill the forces overwelmed it and by then the fall direction has been determined, assuming the hinge is a constant width along the entire tree diameter. just a thought 


steve

[Kevin]

Steve;
This would be more prevalent on a narrow face and slower to react on an open face.
The quicker the pinch occurs the quicker the holding wood starts breaking causing the tree to fall off the intended lay.

[ID4ster]

Right on!
The notch closes first on the high side breaking the hinge wood on that side first causing the tree to roll out.

(Image hidden from quote, click to view.)

That doesn't make sense. If the backcut was at the same angle as the initial undercut and the hinge was the same width all the way across than it should not close on the top side first unless you have a dutchman up there that would cause problems even in a level cut or the tree is so heavy with limbs on the downhill side that it pulls the tree that way anyway. If the top were to close first the angle of the undercut would have to be so severe that the tree wouldn't be safe to fall anyway. In any case you could level out the undercut before starting the back cut or angle the hinge so that the top was wider than the bottom which would compensate for the closure. If the back cut is the same angle and width though the tree should fall in the direction of the face cut well before the top part of the hinge closes.

[Kevin]

This wouldn't have anything to do with uneven hinges, a dutchman or weight distribution.
If you think of the tree falling straight and your cuts not being square to the tree do you not think there might be an affect on the direction it falls?
If one side of the face is higher than the other and the tree is falling straight will one side close sooner than the other?
What's the purpose for making a face square to the tree on a leaning tree?
I could be wrong.






...but then again, I could be right. 

[Reddog]

Kevin,
The tree will not fall straight to the stem, it will follow the hinge. So the face will close equally.
You can use a angled face cut to help steer the stem on leaners. Only to a few degrees, but it helps.
Also I have used it to steer around another trees limbs hanging in the way.

That was why I ased about the back cut. If it is not parallel, then the hinge will caude the face to close unequal. Doing exacly what you discribed.

Just my .02, which may not be worth much.

[LEES WOODCO]

Right on!
The notch closes first on the high side breaking the hinge wood on that side first causing the tree to roll out.

(Image hidden from quote, click to view.)

Bull Schnickeys!      For example - A door hinge always closes the same way no matter if it is verticle , horizontal or at an angle.

[Kevin]

Remember the hinge on this tree is closing and starting to break so what you are left with is half a hinge and holding wood which is now pulling on the tree.

[Maineloggerkid]

I am in a class right now where this happens all the time, because the first year kids dont have a clue what they are doing, and I will admit- I do it once in a while, too. It does affect your aim, but not dramaticaly. It also seems to depend on the size of the bole, wieght of the limbs, lean of the tree,etc.  I have used an unlevel face cut as a felling technique before on a tree that was leaned hard in the opposite direction of the hole I wanted it in. We have to swing our trees using wedges and other techniques because the instructor wont let us pull them with the skidder. ONly becuase we are going for our CLP liscence and we our supposed to learn such skills.

[Kevin]

Kevin,
The tree will not fall straight to the stem, it will follow the hinge. So the face will close equally.

I would agree that it will not fall straight to the stem but one side will close faster than the other

You can use a angled face cut to help steer the stem on leaners. Only to a few degrees, but it helps.
Also I have used it to steer around another trees limbs hanging in the way.

I wouldn't use an angled face cut to turn a tree

That was why I ased about the back cut. If it is not parallel, then the hinge will caude the face to close unequal. Doing exacly what you discribed.

That's due to the uneven hinge wood pulling on the tree and not the apex of the face

Just my .02, which may not be worth much.

Worth just as much as anyone else on this forum 

[Radar67]

I think the effect of gravity might have a lot to do with it breaking on the high side.

[Black_Bear]

"What's the purpose for making a face square to the tree on a leaning tree?"

So the tree doesn't split.

For a heavily leaning tree I will create a Humboldt notch, then bore into the tree about an inch above the hinge point, start at the notch, create the hinge and cut back, leaving a strap that is proportional to the tree size, I guess about 8" on a 30"-on-the-stump tree. Then cut within that 8" strap about 3-4" below your back cut to release the tree. A safety notch.

I generally use the natural weight, a thicker hinge (1") and cut off about half my hinge (half the diameter of the tree) to turn a tree. Wedges work good also.

Ed   

[Kevin]

Why would the tree split if the face wasn't level and the felling cut matched the face?
Isn't any splitting prevented by boring the tree to remove stress within the tree?

What about a back leaner, or a side leaner?
Not all leaning trees are head leaners, right?

[SAW MILLER]

 I just folded a piece of paper to make a tree one inch wide and folded a hinge 90 degrees.The tree fell staight.Then I folded an angled hinge and was suprised at how far to the side the paper tree fell.
  I guess you can teach an old dog once in a while

[bg372]

hahahahaha does anyone on here actually cut wood. you are completly right with the paper thing. that is actually the way are instructor taught us last year.

[beenthere]

Welcome to the forum bg372

Many, and maybe most, on here actually cut wood....hahahahaha

[Dan_Shade]

this has me wondering.  I think a scale model may show some interesting finds.  i flat peice of paper won't quite show what's going on, I dont' think...

the tree wants to fall on a horizontal hinge, due to gravity, if the hinge is angled, then I'd think gravity would cause it to bind, and rip away on the high side the way Kevin says it would.

There are a lot of variables in falling a tree.

[SAW MILLER]

Welcome to you bg372.Yes,I have been cutting trees off and on for around 40 years
 When I started cutting there weren't no schools around or any teachers either.I am self taught and its a wonder I was not killed learning.
      I reckon I have cut a few hundred trees down but I learned more from this forum.

[rockenbman]

  never tryed the unlevl face cut not 2 sure about what might happen.looks like it would start out right then break uneven on the left side face.

[Dan_Shade]

Do any of you guys have stump pictures with angled cuts?

[rockenbman]

  well the next dry day i can get back to my favor spot for cutn i might b temp 2 try the uneven cut.If i were sure what the tree going 2 do.

[Cedarman]

All this begs the question.  Why not use a level cut and use the open face felling method with wedges to make the tree fall in the direction desired? The angled cut seems to be less controlable.

[Kevin]

That's my point exactly!

If you don't know what you could be doing wrong it could be contributing to a less desired outcome.
Once you understand the mechanics of what's happening to the wood it's easier to predict the outcome and when you do everything you know to be right and something in the process fails then it's important to know what it was to prevent it from happening again.

[Black_Bear]

Kevin, I agree 100%. But sometimes experience is the best teacher. Most of the guys I learned from couldn't begin to explain the physics of what is happening during the process of felling  a tree, but they could tell you what you did wrong and how to correct it.

"Why would the tree split if the face wasn't level and the felling cut matched the face?
Isn't any splitting prevented by boring the tree to remove stress within the tree?"

Yes, boring the tree usually prevents splitting. But not everyone will bore a tree and if all of the cuts are not correct then the chances of cutting through that tree before gravity takes over diminishes greatly. The safety notch I described works excellent with heavy leaners.

Talking about cutting down a tree and doing it are two different things. Usually I have the area I am working in set up so that I can drop a tree where it wants to go, especially in larger northern hardwood. I generally work in a horseshoe pattern so that the wood can go in just about any direction it has to.

But, I digress and I'm getting off topic.

I'll try to get some pictures today. Don't know if I can with all the snow??

[Ed_K]

 I've done the angled cut many times to roll a tree. It won't land very far off the original line, a few degrees. I use it to turn a big leader or miss branches in another tree. What I have found is that there is a lot of fiber pull doing this. May ruin a whole 1/2 log (1st 8').So if your cutting for saw logs use a standard cutting practice and aways use wedges.

[logwalker]

Add a rotten heart to the equation and what happens. 

[Kevin]

We have a video of that too. 

[tomtrees]

hi I am new to the forestryforum.
Just to through a thought into the disuction, If the back cut was flat and in the middle of the gob, would not the holding wood under the hindge hold longer being difficult to brake and the holding wood the high side of the hindge brake first pulling the tree to the left as we look at it.
I have tryed this with a flat gob and a *pithed back cut it seemed to pull the tree round a couple of degrees.
Would any one aggree?

[rebocardo]

> Do any of you guys have stump pictures with angled cuts?

Not as angled as the drawing shown, I would be too afraid to go that extreme :-D

But, I didn't need too much to get the tree where I wanted (95 foot oak in a 90 foot yard).  Plus, I had another FF member coming to saw it up and wanted to leave some good wood without pulling the heartwood apart.

Small open angled notch, hinge way forward because I wanted to do a lot of lifting and wanted the leverage, plus, I wanted to keep the tree on the stump as long as possible without a barberchair using as big of a hinge as possible (big oak, lots of little houses), I cut a triangle holding wood to direct the tree along with the wedges and notch.





Went better then expected, I was pleased, and the midway limbs held the top off the ground barely over the chainlink fence, so no expected fence damage 

[Kevin]

Why is the back of this hinge angled?

[Kevin]

tomtrees;
Welcome to the forum.
The thicker the hinge wood the more holding power.
You would normally leave the hinge thicker across the width of it rather than making alterations to the height of it.
This is called a tapered hinge used as you describe in helping to pull a tree in the direction required.
I hope I answered that for you.

[bg372]

sry bout the hahaha, i gess i dont understang why u would think cuting the hinge like in the pic would help you in any way. even though i wasnt there and dont know the lean or anything so ill say its got slight if any lean to it headed the felled direction. i would think u want a even hinge,level back cut, open face notch so it wont close all the way and 3 wedges to be safe one on each side and one at the back. cut notch,bore in, create back strap set wedges and relase. thats my opinion and im curios to see what other people would have done. see what some other teqnecs are out there.

[Bill E]

Interesting topic.

My two cents is that if the notch in Kevin's original diagram is open face and the hinge stays intact to the ground the way it should, the tree will fall to the left side in Kevin's diagram.

Bill

[Kevin]

Why is the back of this hinge angled?

This is usually an indication that either no saw dogs were on the saw or the dogs weren't anchored to the tree.
Normally seen with more of a rounded back, makes the hinge stronger than desired.

[rockenbman]

 What I usualy do is - look at the tree and others around it try to make my notch about 22" above the stump in the direction I hope the tree will go,then on the back side make my back cut inline with the bottom of the notch.This work most of the time for me and if not ill use my 4430 to pull them out if they get stuck.

[arojay]

In my experience, a lot depends on how open the face is.  On a normal day I will fell up to 60 trees, then skid for the rest of the day.  I get a few uneven face cuts from time to time for various reasons and if the face is open the tree is down before the effects of the uneven cut show up.  This would be more critical for arborists working around values.

[snowman]

Interesting discussion, lots of theorys to ponder. I think ill just do like I have always done, cu t the tree down, hope for the best and run like hell!

[bg372]

i hope when u say about 22 inches you mean like 6 or 8. 22" thats a high stump hight. anybody ever try any humbolt knotches. i personaly usually use conventinal

[rebocardo]

> Why is the back of this hinge angled?

Tree was about 40"+ across where I was cutting (with a 28" bar) and it had a lean. So, I took it from both sides making sure I left a lot more hinge on the upper side. Normally I would have made an upside down triangle type of wedge. But, cutting from both sides, I wanted to make sure the middle and upper side stayed thicker and the lower side thinner. I marked it out before hand on the tree how wide I wanted the final hinges. Then I gingerly cut while applying wedges and watching for lean.

I was leaving as much hinge as possible on the high side and cutting it as much as I dared on the lower side until I got it lifted enough with wedges where it would not fall sideways (on me and a house - had three cables on it though)  and was upright and the center of gravity (standing straight) was correct for a pull down with my 4x4 van.

I was going to cut more to make the hinge a bit more even, but, felt I had enough left to hold in the middle and enough removed from the lower side so I would not be ripping the trunk out of the ground.

I was going to cut some more when something inside just said " you cut enough hinge, pull it down", so I did 

My goal was not to rip the trunk from the stump, I wanted it to stay attached with the hinge until the tree hit the ground and I got it delimbed. It was maybe two feet from a deck, the last thing I wanted was for the tree to break free and kick back or roll. I did not cut the hinge until there was about 20 feet of trunk left.

I usually use a low open faced notch with a level even backcut, but, not always. I justy happened to have pictures of this one because I was turning the tree into lumber with a FF member.

[Kevin]

That was just a tidbit of information I was offering to anyone that was experiencing a problem when using wedges to lift a tree.

[rockenbman]

 Most of the time im workn in a fence row were farmers want clear cutting work done.I leave a 22" - 24" stump for the dozer to push out latter.Its usaly thick with under brush and slow to go work.

[Dale Hatfield]

hinge wood actually bends. Excess hinge  breaks to allow the hinge to bend.
Rule of thumb for hardwood hinge thickness is 10% of DBH. Anything thicker than that is running risk of splitting the log or Barber Chair .
Pulling A tree over with excess hinge wood ,could  lead to a barber chair, as top is falling faster than wood (hinge )can break or bend to keep up with falling top.
Dale

[Kevin]

At least one exception to that would be frozen wood Dale.
Frozen hinge wood doesn't co-operate at all.
It usually shears across limiting the mechanics of the hinge.