Sloping Back Cuts - Why Not?

[Nutball]

Not sure how I missed this thread originally. As an arborist I'm presented with precision felling scenarios on a regular basis. If a fall goes bad it will result in significant property damage for my clients. In short I get paid to get it right every time.

Many good points to avoid a sloped back cut were made, but I'd like to add the sloping back cut is most dangerous on forward leaning trees. It gives the false sense that it will mitigate barber chair when in fact the opposite is true. We all know that a barber chair is caused when the top of a falling tree moves faster than the saw can sever fibers in the back cut. In addition to the extra distance that needs to be covered, the sloped back cut is closer to a rip cut than a cross cut making it one of the slowest felling cuts you can make. Thus, there is an increased risk of barber chair with the sloped back cut. This fact coupled with the complacency instilled with the false sense of safety make the sloped back cut a bad idea.

With a sloping back cut, the barber chair would more readily get jammed up by the higher point left in the stump, though you do make a good point about speed. Either way, don't make a sloping back cut.

 

[Philbert]

With a sloping back cut, the barber chair would more readily get jammed up by the higher point left in the stump, . . .

Depends on what kind of momentum and leverage it has . . .

Philbert

 

[Nutball]

Right, because it could just as easily split out the back of the stump.

 

[Woodpecker]

With a sloping back cut, the barber chair would more readily get jammed up by the higher point left in the stump, though you do make a good point about speed. Either way, don't make a sloping back cut.

It seems like it will but it won't really. Say the tree is like the face of a clock. With some forward lean it stands at maybe 12:30 or 1 o'clock. A barber chair is likely to happen when it gets to just before 2 o'clock in its fall. By then the distance between the two faces of the now opening sloped back cut is typically too great for them to meet in the occurrence of a barber chair. In the rare event they did meet it will most likely slab the the stump and still barber chair. The problem is we are talking literally tons of force. That's too much of an ask for a small piece of static wood to stop. This all can be tested with 3-6" saplings and a hand saw in the woods.

 

[RI Chevy]

I thought sloping back cuts were not good due to weaker surface for wedges? Flat on flat provides more lifting strength. As compared to trying to use wedges to lift on an angular cut.

 

[Woodpecker]

I thought sloping back cuts were not good due to weaker surface for wedges? Flat on flat provides more lifting strength. As compared to trying to use wedges to lift on an angular cut.

Yes if you read back through the thread that point was already made. Wedges tend to slab the stump when used with a sloped backcut.

 

[RI Chevy]

Ok. It's an old thread that was resurrected. TY sir.

 

[morewood]

I'm a simple-minded firewood hack, but appreciate these explanations and even understand most of them. For me, a sloping back cut never made sense from a physics and time perspective. I can make a sloping cut and change the leverage generally in a bad way and also take longer to cut the same thickness of wood compared to cutting horizontally in. Just how my brain works. I prefer to think things out BEFORE I cut.....I don't want to be on a Darwin video.

Mr Awesome

 

[Woodpecker]

Ok. It's an old thread that was resurrected. TY sir.

Jeff I was really surprised to get 4 pages in and see good advice, but not see what I view as the most important reason to not use a sloped back cut. Even on perfectly straight trees it's going to increase the chances of barber chair. I always try and recommend the bore cut to Joe Firewood.

 

[RI Chevy]

I've seen several bore cuts done on leaners. I've sought advice and done a few.
When I cut regular straight up trees I just go very simple and traditional.
Perhaps if you get the chance maybe you could do a video demonstrating a bore cut on a straight up tree?
I just don't feel experienced enough to bore cut on a regular tree. I'm just a firewood hack.
I've seen some veneer cuts that are done by bore cut. Is that what you're referring to?

 

[huskihl]

There’s probably more science to it than what I’m seeing, but on a tree with no lean, I would never bore cut it. I would rather start my back cut and get wedges behind the bar as far away from the hinge as possible for added leverage. Pounding wedges right next to the hinge has to add stress to the holding wood without as much lift as being further away from it.

 

[Philbert]

on a tree with no lean, I would never bore cut it.

People learn methods and practice those. Some only learn a conventional cut. Some may only learn a bore cut. Some may do things a certain way 'just in case' something unexpected happens.

I am not into fancy or 'trick' cuts, but after learning about the bore cut, many years ago, I liked to practice it on trees that did not need it to build a little skill. On trees too small of a diameter to bore cut, I try the 'Coos Bay' (triangle) cut that I learned in these forums.

I am not a professional tree cutter. But just as doctors 'practice' medicine, and attorneys 'practice' law, I like to try things out and learn from each tree. That is why I wanted to understand the 'why' behind the sloping back cuts too.

Philbert

 

[huskihl]

People learn methods and practice those. Some only learn a conventional cut. Some may only learn a bore cut. Some may do things a certain way 'just in case' something unexpected happens.

I am not into fancy or 'trick' cuts, but after learning about the bore cut, many years ago, I liked to practice it on trees that did not need it to build a little skill. On trees too small of a diameter to bore cut, I try the 'Coos Bay' (triangle) cut that I learned in these forums.

I am not a professional tree cutter. But just as doctors 'practice' medicine, and attorneys 'practice' law, I like to try things out and learn from each tree. That is why I wanted to understand the 'why' behind the sloping back cuts too.

Philbert

I suppose “never” wasn’t the proper word. I’d do it to learn on smaller trees just like you mentioned.

 

[Stump Shot]

People learn methods and practice those. Some only learn a conventional cut. Some may only learn a bore cut. Some may do things a certain way 'just in case' something unexpected happens.

I am not into fancy or 'trick' cuts, but after learning about the bore cut, many years ago, I liked to practice it on trees that did not need it to build a little skill. On trees too small of a diameter to bore cut, I try the 'Coos Bay' (triangle) cut that I learned in these forums.

I am not a professional tree cutter. But just as doctors 'practice' medicine, and attorneys 'practice' law, I like to try things out and learn from each tree. That is why I wanted to understand the 'why' behind the sloping back cuts too.

Philbert

Well, I'm no expert at falling trees by any stretch of the imagination, I consider myself a student and if something looks too hairy I get proper advice from a Pro.
I do however happen to know a guy that has fell with a sloping back cut all his life. From what I can gather, he gets away with it mostly because he's an excellent judge of tree lean. As for the why, the thinking is it would stop a back lean quicker(better).
As far as to the why not, the way it was told to me, it can make a bad situation much worse when it enables the tree to slip off the stump and is now falling towards you, the cutter.
That said, I make sure I'm three tree lengths away from him when he's cutting because it scares the crap outta me.
The good news is, that in repairing chainsaws I get to know several loggers and tree cutters that are happy to give sound advice to me and I listen and deploy their words to the last detail and It's always worked, just like they said it would.

 

[Philbert]

. . . .if something looks too hairy I get proper advice from a Pro.

Dang! You were the one I was gonna call!!!

Philbert

 

[Stump Shot]

Dang! You were the one I was gonna call!!!

Philbert

Sorry

 

[Woodpecker]

On straight trees out in the woods with little to no concern if the fall goes sideways there really isn't a need for a bore cut. That is also the perfect place to practice unfamiliar techniques though. In an urban environment where I cut most often I use a bore cut almost always. The extra control is just an added layer of safety. I also use it in the woods because it's easy (for idiots like me anyway) to judge a tree with a little back lean as straight. The bore cut keeps that tree from pinching the bar before you can get a wedge in. Beyond not using a sloped back cut, there really are many ways to fell a tree safely. The important thing is to stick with what your comfortable with.

Perhaps if you get the chance maybe you could do a video demonstrating a bore cut on a straight up tree?

Probably never happen. I'm no gopro hero and rarely have a camera man available for a video. Plenty of pics of my work in the not so pro threads though. My buddy Mark has one of the best borecut videos out there:

For smaller trees or if I'm worried about putting stress on the hinge with wedges from the side I will use a modified bore cut that Husky calls the safe corner:

This one allows for the wedge to be used at the traditional back of the tree location.

 

[Woodpecker]

I do however happen to know a guy that has fell with a sloping back cut all his life. From what I can gather, he gets away with it mostly because he's an excellent judge of tree lean.

As a kid I remember watching the farmer next door to my grandpa's farm drop every tree in the shared fence row with a sloped back cut. It worked because every tree was leaning into the pasture. Was probably 15-20 trees of various hard wood in the 20-30" range. Every single one barber chaired. I thought that was how it was done. I didn't know any better at the time.

 

[Lightning Performance]

When Brad mentioned the stump slabbing out and it breaks lose... that shock chairs hollow white oaks live or dead like a trip hammer. Get your biggest saw, a longer bar and have two exit plans and no ear muffs just plugs so you hear it break.
A rope hooked to the truck is not a bad idea. These are not trees your pulling against the lean even if you cut them at ground level. I don't like being low and closer to the mfers, no franks. I have one crushed pole saw head that keeps me humble. I'm not scared to crush another one. Three chaired in one day before. All white oak, hollow. Norway maples or sassys tend to do that more than oaks. They all chair sometimes and that sloping back cut sets them off in my opinion when the stump splits.

 

[Maintenance Chief]

Sometimes I think its hard for someone to believe that a couple little wedges can move or direct a huge tree, and they think there's a work around.
It is pretty amazing that a tiny (in comparison to the tree) peice of plastic will lift a tree , I often hear people say that they don't know about me felling a tree opposite of a slight lean , I think that could be one motivation for the slope cut.