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Angled back cuts

brendonv

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Mar 6, 2005
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I am speaking of the typical "homeowner" cut. Notch it then do the angled downwards back cut. I know this is wrong, I see it often and would like to tell them why it's wrong with a educated answer. And I don't quite have the answer.

Anyone up to schooling me? :)
 

sawinredneck

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I did this on a large codom Hedge tree thinking it would stop barber chair.
I did about everything else as wrong as wrong can get!! I ended up BELOW the bottom of my notch and if it weren't for wedges, and lots of them, I was SCREWED!!!!!
I got really really lucky!! I forget why else not to do it, but that was enough for me!!
 

Skwerl

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The reason it doesn't work is because it doesn't allow the feller to make an accurate hinge. Felling isn't about what you cut, it's about what you don't cut (the hinge). The angled back cut is made by fellers who do not comprehend that concept. They somehow believe that the action of cutting somehow steers the tree. Once a feller fully comprehends the concept of hingewood then he is much less likely to continue using a sloped back cut.
 

NickfromWI

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You could also refer them to "The Fundamentals of General Tree Work" chapter 25, "The Backcut."

Simply point out that the angled back cut is not even mention in this extensive masterpiece.

love
nick
 

Stumper

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Besides the greater difficulty in having the finished back-cut line up properly with your face for the intended hinge the principle problem arises when using felling wedges...instead of all of the force from driving your little pocketable inclined planes being directed vertically to lift the back of the tree and TIP it forward, some is driving the tree forward. That doesn't sound too bad but it may cause a hinge to fail prematurely,driving the butt forward and allowing the tree to trip backward. At best it is simply less efficient than a level backcut.
 

lumberjack

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Furthermore, in a wedging or sit back condition, the forces are working with the grain as opposed to against it. What can very well happen is the stump splits, and that is the start of a bad day.
 

sawinredneck

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Furthermore, in a wedging or sit back condition, the forces are working with the grain as opposed to against it. What can very well happen is the stump splits, and that is the start of a bad day.
EVERYTHING that day was BAD!!! I totally had my head up my butt that day!!!!
It did set back on me, and I was ready to run!! I think about six or eight inches of the butt was sitting on the back side of the stump. It was a heck of a clean up!! Not sure how familiar you are with Hedge trees, but nothing grows straight!! It would have been really nice to had that 36" tree sitting on the ground and not worry about which way it was going to roll off that stump!!
 

Old Monkey

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People think that an angled back cut will make the tree go in the downhill direction. The only way it works is if the tree leans that way already or if it is a small tree and they turn their bar in the cut. What they don't realize is that when you cut through a tree you are removing a strip of wood that we call a kerf. The kerf is in a sense a face cut and causes the tree to want settle towards the side you are cutting on unless the lean is away from the cut. The slope of the cut does not matter as a level kerf and a slanted kerf will react just the same. The tree doesn't "feel" the slope, it only knows that you've removed the thickness of your kerf from one side of the tree.

In your scenario someone put a correct face cut but then used a slanting back cut. The reason the slanting back cut is wrong is because:

1. The angle doesn't make any difference to the tree.

2. Cutting at an angle is slower which gives the tree more time to barber chair if it is going to. On heavy leaner you need to get through the wood quickly.

3. Where you finish you back cut is important and cutting on a down slope makes that much harder to get right. Judging correct stump shot and an even hinge while cutting a down sloping back cut is tricky.

4. If the tree settles back on your saw in the back cut, wedging will be difficult to impossible.

I hope that answers your question.
 

sotc

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darins number 4 is what i usually think of. your wedges are pushing into the hinge instead of lifting the tree. like trying to open the door by pulling the knob toward the hinge instead of the normal 90 degrees from the hinge
 

gf beranek

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Yeah, angled backcuts don't do it too well. For so many valid reasons already mentioned.

The fact that so many people have used them and still do makes me wonder how the logic is passed on.

Is there some secret "layman knowledge" that we're all missing.
 

GASoline71

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If you have to wedge the tree at all... it will try to push the spar off the hinge, insted of lifting the spar in the intended direction. So it works against your hinge wood.

There are a lot that also think it is going to save them from stump shot... but it will just make the butt kick up higher.

Main reason I see is you don't have as much speed and control when doing an angled back cut. Think about when you are making a proper face cut you are coming through the grain of the wood at an angle. Even with a laser sharp chain you usually are throwing a lot of saw"dust" instead of chips on an angled face cut. It takes a little more time.

When you make a proper back cut (or when you make the gunning cut in a Humboldt) notice that you are tossin' nice chips with the saw chain... your cut is smoother, more controlled, and when you need it to be... faster. You're cuttin 90 degrees from the grain of the wood.

It just compromises way to many things in a proper 3 cut.

This topic came up over at AS... and the certified fallers in BC chimed in and said that is illegal up there to make an angled back cut. Prolly not illegal for homeowner Billy, but for the pro guys yes.

Gary
 
B

Bounce

Guest
You should always make your back cut level and about 1-2" above the level plane of the face cut (notch) in order to leave a surface that the tipping trunk can push against to prevent it from sliding back over the stump towards the sawyer. As the tree is falling, the butt is getting pushed by the top in the opposite direction the top is falling in. If the back cut slants down towards the face cut instead being slightly above it, you've created a ramp for the butt to slide up towards yourself as the tree tips over. This isn't quite the same as a barberchair though because the wood hasn't actually split or broken. As I understand it, a barber chair is when the trunk actually splits along the grain sending the part above the back cut towards the sawyer, usually due to a heavy lean and/or brittle wood. The effect is the same though, which is pretty bad - people and trees are about the same relative size as baseballs and bats.

I think the Fundamentals of General Tree Work should be required reading, especially the section on falling techniques. This was my employee training manual when I first got started, and I had to pass a written test to prove I had read it (all 500 pages) before I could even show up on a job site. I've never seen another source of info on felling techniques that was 1/2 as good.
 
N

NeTree

Guest
Furthermore, in a wedging or sit back condition, the forces are working with the grain as opposed to against it. What can very well happen is the stump splits, and that is the start of a bad day.
Precisely.
 

Burnham

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Yeah, angled backcuts don't do it too well. For so many valid reasons already mentioned.

The fact that so many people have used them and still do makes me wonder how the logic is passed on.

Is there some secret "layman knowledge" that we're all missing.
I'll just tag on to Jerry's post with a ditto.

It truly is a curious thing, how so many folks do this. I wonder if it isn't just some vague idea that goes like "I know there's supposed to be an angled cut in here somewhere...". I don't think logic, even faulty logic, plays any role at all :).
 

Stumper

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Burnham- It is also like topping-Tree stuff done wrong shows up better than tree things done right. Thus Joe Nonothing notices the bad and emullates it. I can show you sections of Colorado forest where virtually every tree harvested was taken with an angled backcut. Those stumps stick up saying "Look at me. Cut it like this."
 
M

Mike Maas

Guest
Precisely.
Exactly. :D

If the back cut is slanted enough, just the weight of the spar sitting back can split the stump and let the tree fall back.
And if you have to wedge the tree, the wood just bends or splits and the wedges don't have any power.
 
M

Mike Maas

Guest
If you have to wedge the tree at all... it will try to push the spar off the hinge, insted of lifting the spar in the intended direction. So it works against your hinge wood.

Gary
Let me think about that...umm...uhhh...Nope.
In that thread at AS, the egghead engineers did the math and it put more force on the tree, because of the greater distance from hinge to wedge, increased by the angled cut.
What math they failed to take into consideration was the weakness of the wood the wedge pushes against.
Where is Spyder when you need one of his long complicated explanation/drawings?
 
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