Barber Chair question

[wradman]

try this

if you look in the thread tree half way down i put in an attatchment that relates you your question also.
If your having problems with barberchairs with trees that do not have a heay lean, you are not using proper falling techniques.
The only time you have problems with chairs are in heavy winds,or hard leaning trees, The species plays a part roll but your cuts lining up are the most important , spend a little more time on your undercut and you will be surprised what you can accomplish, after about 10 years of production falling you won't even think about it .
if i don't have to wedge it a 2 foot spruce takes me less than 2 minutes from start to finish

 

[BlueRidgeMark]

Most would recommend the boring back-cut in preference. One caveat I'd suggest is that you break up the continuity of the hinge.

Is that to weaken the hinge so that it will break before a barberchair can happen? Make the hinge the weak link?

 

[clearance]

The oldest cutting method of avoiding a barber chair is the triangle back cut; it dates from the cross cut days.

Put in your face, your back cut is in three cuts.
The first two come forward at about a 45 degree angle pointing in.
They go through actually into the undercut just near the outer edge of the hinge, usually by 1-3", depending on the size of the tree.
So the holding wood is "nipped at both corners". The first two portions of the back cut form a triangle.
This is done on heavy leaners that you are dropping with or very close to the lean.

Then, with a sharp saw, properly tuned, full tank, you power through that baby and get 'er done. It wasn't uncommon to hear old school loggers remark that you'd be a fool to leave the trees once it starts splitting. Got to see that cut all the way through or you're in trouble sonny boy.
Extremely important that the holding wood gets nipped at both corners.
No wedging, of course on a heavy leaner.

Most would recommend the boring back-cut in preference. One caveat I'd suggest is that you break up the continuity of the hinge. That could be with nipping the corners again or a face center bore prior to back cut. I'm saying that as I've read several accounts here on arborsite that are of plunge back-cutters that did not do that and had barber chairs. Seems to be more likely in ash.

I've changed my procedure because of what I've read here.
I'm actually doing a face center bore first, then face cut, then corner nip, then bore back. Based on a posts from John Ellison, and others.

I like my holding wood to be intact on leaners, not nipped, other than that how you decribed is what I do. Of course there can be a little more to it, like cutting a little of the backcut from the undercut, you have to make sure that the rest of the backcut is a little higher though, not matching the undercut. Whatever makes you happy, a powerfull, sharp saw that is full is a must.

 

[smokechase II]

barber chairs

Wradman:
"The only time you have problems with chairs are in heavy winds, or hard leaning trees,"

There are other times where chairing should be guarded against.

1) This is an arborist site. Many of these guys here pull things over with ropes to pick-ups, jet skis or their buddy. The rope stuff is going to be obviously a copy cat to the wind effect.
2) One tree leaning into another. If you are cutting the tree that is being leaned into be ready again for the wind equivalent. (Of course, not approved)
3) Defect in the tree. You may or may not be able to spot this from an external inspection prior to cutting. It's not a perfect world. Be ready with alternative escape routes.
4) Your face cut matching up with a split in the tree. Picture your face being parallel to and about 4" short of a split in a 30" leaner. Bingo.

Noted that you mentioned a 2 minute time limit on spruce.

 

[smokechase II]

Weaker hinge

BlueRidgeMark:

"Is that to weaken the hinge so that it will break before a barber chair can happen? Make the hinge the weak link?"

The way one faller described it to me was that if the holding wood was broken up, it wouldn't be as likely to hold together enough to move the fulcrum up the tree.

Obviously, at least one objective is to get the hinge to break before a chair can occur. But I think a more correct way to state it is not that the hinge is the weak link, but that it is weaker from a chair producing perspective. With a face center bore, you could still have the same amount of square inches of hinge, (the hinge would be thicker - but because it is missing some from the center it could be the same size or very similar in size). This hinge wouldn't necessarily be weak, just constructed differently.

There are differences in the strength and flexibility of the heartwood and sapwood. This actually could get into a fairly complex discussion with regard to which wood would be best removed to break up the hinge continuity on any given tree/species etc.

Clearance makes the point that back-cut height to face height can influence chair potential.
This can work two ways.
Most of the chair stumps I see in Eastern Oregon have a small face and a back-cut that is too high to work with the face. This ineffective back-cut height can be viewed as falling without a face cut.

Check out the photo in the next post:

Note that the photo is of a cross cut tree (we're dry here-things rot slowly) from circa 1935.
You can still see the axe marks on the top of the face etc. We had a big railroad logging effort back in the first half of the 20th century.
Photo was taken in late 2004, as I recall.
Mostly note that the back cut height to smaller face was the problem.
(There was no dutchman - chopped out a proper conventional face)
The tree has rotted just a little, some of the outer wood has gone, but not enough that it would make this a legit face.
Trivia, the were more stumps in the area that showed that these guys were rookies.

Then there is the view that hinge wood should be thought of not in square inches, but cubic inches. Right Clearance?

 

[smokechase II]

opps here is the photo

 

[BlueRidgeMark]

Interesting. Thanks for the detailed response, smoke.

How would those cubic inches be measured? The square is easy enough - it's the cross section of the holding wood. So, take that cross section multiplied by the vertical distance from the back cut to the angle of the face cut?


BTW, you have to upload that image before we can see it.

 

[smokechase II]

cubic inches

Vertically:
Length (across the tree) x width (distance from apex of face to same plane as where the back-cut ends) x height (distance of back-cut above face.)
Awhile back someone had a post where they believed that a slanting back-cut, where one side is higher above the face, that the higher side had a greatly holding power than the shorter holding wood.

Now here is the key.

I don't have a clue.

My falling has been very heavily limited to dead or damaged trees on fires, cleaning up dead stuff etc. and thinning smaller pre-commercial stands.
When you cut dead or dried wood, you are cutting material that is much less likely to barber chair. I've never had a barber chair. My knowledge in this area could be viewed as he must be good, or more correctly, lacking.

So for all those reading on this site and you find something that could be from a rambling bozo. Beware. I am your second worst nightmare. Play your hand cautiously like BRMark has done here.
"How would those cubic inches be measured?" "Is that to weaken the hinge so that it will break before a barber chair can happen? Make the hinge the weak link?" Haven't I seen you on one of the poker shows on TV?

Best bet, book learn, then most importantly, find that local or three that seems to be really good and figure out what you can from them in the timber you deal with.

Trivia: I have heard the cubic inch theory, and read here of the higher holding wood. But I'm not gonna milk this any further. Bunch of the other stuff about barber chair avoidance I do believe to be accurate. But double check with your local skilled craftsman to be sure.

 

[Tree Machine]

Awhile back someone had a post where they believed that a slanting back-cut, where one side is higher above the face, that the higher side had a greatly holding power than the shorter holding wood.

We've had entire threads on this topic, one juicy one discussing a TCIA article whose image made the cover of the magazine. The author was our own Murphy4trees. It's called the tapered hinge; Many of us use it extensively, both in felling and aerially for accurate directional lopping of limbs.

Here's an image of a barberchair I created last week. This one was deliberate, a wide-open fell, no obstacles, a rope pulling the tree the direction we wanted it to go.

The 'mistake' was the back cut coming in at the level of the face cut, too low. The pulling of the tree is essentially the same as a leaner. When the tree starts to go, the feller stops his cut and bails, stopping short of a complete back cut. If the back cut is at the proper vertical distance above the face cut, and the back cut is not aborted too soon, the barberchair can most often be avoided.

This back cut was too low and didn't go in far enough.

 

[wradman]

chair

first things first there is no 2 minute time limit i was just mentioning the app time it takes when you have been doing it for a lot of years to give a perspective of the ease of repitition.

Yes you are right about arborists pulling trees gives the same effect as high winds,there are things you can do to lessen the effects
1- put a little more angle in your undercut ,this means the tree will be farther over before the undercut closes.
2- spend more time training the person pulling on the tree, i've pushed and pulled alot of trees , all you want to do is win the direction of the tree which means once the tree is positively going in the direction you want it to go let the undercut and holding wood do the rest. By forcing it or continuously pulling you are putting exesive stress on the tree and the holding wood.
3 - barberchairs are caused by the undercut closing then the holding wood binds causing the weaker stem wanting to split,when you are on the ground it is always the tree side when you are in the air it can cause the trunk to split pulling the rigger of faller into the tree ,then the trunk will pull you into the tree ouch.
4-there is no difference weather the under cut is higher or lower i find perfect matched cuts work the best but are against the trained practice, we are taught to put the backcut in slightly higher to reduce the risk of the upper portiion hanging up on another tree and sliding backward over top of the stump causing the effect of kick-back.
5-if your are up a tree where there is no escape route take extra time to ensure your undercut is clean, when you do your backcut you can't leave anyhow so leave your saw in the cut, when a tree barberchairs you can tell when it is going to it starts to bind severely(this is where your guy on the ground needs to know not to pull excesively)you have about 1.5 seconds if the tree starts to bind there is time to cut a little more wood.
If you get to worried about barberchairs the next thing you will do is start cutting to much wood then that is worse yet then you will start cutting to much wood off , so if time permits check your wood on the other side of the tree whenever possible.

sorry hope i wasn't to long winded.

 

[smokechase II]

Tapered hinge

Tree Machine:

A tapered hinge is one in which the holding wood is thicker on one side of the tree. This to pull the tree toward that side in the fall. Think two dimensional or square inches.
Take that same or another hinge and focus on either raising it or placing it at a slightly out of kilter angle and we are now in a three dimension discussion. I.e. cubic inches.
I try and cut as level as I can and have basically no experience in the intentionally angled back or face.
So to clarify; where I stated, "Awhile back someone had a post where they believed that a slanting back-cut, where one side is higher above the face, that the higher side had a greatly holding power than the shorter holding wood."
I was not talking about a tapered hinge. I was talking about the three dimensional thing with an angled cut.

Just as a side bar. I don't believe that for a minute that the higher side is stronger than the lower side of that hinge. It is just less effective in its relationship to the face.
Example: One places their back-cut a few feet above their face. Ineffective and you are falling without a face. One matches their back-cut exactly with the apex of say an open face and the back-cut is at an optimum placement to work with the face. This is why the Open face technique of smaller faces works on faces that only go in 20-25%.
So every time we move our back-cut up just slightly, we are moving further into a less effective relationship between the back-cut and face.
Why this distinction is important is for those trees where it is necessary to use a fair amount of wedging and also a technique that will help pull the tree to one side. If there is a less than efficient back-cut to face relationship it could make driving those wedges either extremely hard or impossible. So I would suggest on those, utilizing a level tapered hinge to avoid a stumbling block.
Even though I've never done this unbalanced cut thingy, I can see that it would work. It’s just that I think a tapered hinge (again 2 dimensional) is the cats meow if you got good wood.
Unfortunately, my life has been delegated to dealing with primarily dead
stuff and a tapered hinge has little or no effect in weak wood. So guess what that means.
I should try this angled cut relationship as it probably would work on some of those trees. The ones where there is dried out weaker wood that hasn't rotted.
Hey guys, thanks for talking me into trying this!

 

[smokechase II]

Spruce for time

Wradman:
I was being a bit onery on trying to point out in a round a bout way that spruce is a soft softwood that throws great chips and it makes even me look almost like a logger.
You could have said red fir and I'd-a stayed shut up.

 

[clearance]

We've had entire threads on this topic, one juicy one discussing a TCIA article whose image made the cover of the magazine. The author was our own Murphy4trees. It's called the tapered hinge; Many of us use it extensively, both in felling and aerially for accurate directional lopping of limbs.

This I remember from the thread by Murphy called 6 minute takedown, I refreshed my memory looking on search. Murphy is talking about leaving more holding wood on one side of the backcut than the other, the article is not there but when questioned Murphy said that in the article he explained that it was nothing new. He went on to say that arborists are not fallers nor do they have much of a clue on how to fall trees, properly that is. This post by Treemachine confirms what Murphy said and I firmly believe. If you have to be told about the "tapered hinge" or have it explained to you, then you are
an amatuer in the truest sense.

 

[clearance]

TreeMachine-Also they explanation you give as to why the tree in the picture "chaired" makes no sense. A pulled tree is not a leaner tree cause it is not leaning the way you want, thats why it is getting pulled, no? Seems to me that this tree was pulled on to hard, no reason for a pulled tree to chair otherwise if the cuts are good and proper. The hieght of the backcut is beside the point, makes no diif. unless it matches the undercut and the tree comes off the stump. The backcut should always be level, same as the undercut and about 1"-2" above the undercut. Not trying to beat up on ya buddy, just cut down a lot of trees, kind of know what works.

 

[wradman]

reply

no problem smokey

 

[John Ellison]

I forget if I am agreeing or disagreeing but I dont want my backcut angled in either a vertical or a horizontal plane. Not sure I said that right.
Because if you need to wedge it is a disadvantge. If I need more holding wood or hinge on one side I would vary it horizontally [tapered hinge] instead of vertically.

 

[Tree Machine]

three dimensional thing with an angled cut.

Lots of good info here. And also, please don't view me as trying to step in as the 'expert'. I'm not. I'm not. I just like to get in and stir up the information flow, especially when I've got pictures that help clarify the topic for everyone.

In fact, I'm becoming more clear and smokechase is doing a great job and spending some really dedicated time to make sure we're all on the same page.

Even though the thread is on barberchair and we're getting more into tapered hinge and 2 dimension vs 3 dimension hinging, here's a decent picture, slightly exaggerated, but clearly showing the tapered hinge, and level (front to back) angled (side to side) backcut in all the dimensions, and the result.

The top had been taken out and normally I just block out the firewood chunks, but we had a log arch and needed the firewood at streetside, so decided to drop it and move it out in two lengths. The 30-foot trunk was a slight lean the direction I wanted it to go, non-technical, no obstacles, though the direction of fell was slightly to the left. I was showing a guy the tapered hinge and how to fell the trunk and get it to go slightly to the right.

I set up the tapered hinge so that there was zero holding wood to one side, tapering up vertically. I didn't actually intend to taper back horizontally, but when the tree started to fall, I aborted the cut. that created a 3-dimensional tapered hinge, with a mild barberchair- all the things we're discussing in one image. Had the backcut come in a bit more on the high side, we'd have had a two-dimensional tapered hinge with no barberchair.

And Clearance, on the previous picture you were exactly right. The tree was pulled too hard. I was trying a different face cut with a vertically-oriented plunge to knock out a wide face wedge. I was being too conservative in my back cut (because I had ample pulling power), resulting in a barberchair (see 'previous image' below).

I still don't think we're 100% clear, as the back cut angle can result in a hinge with it's angled dimension, which can be confused (and I read this into Ellison's reply) with the direction of the bar coming in, which can have two dimensions (bar tip up or down creating the tapered hinge, or saw body pivoted on a horizontal plane resulting in the back cut coming in at an upward or downward angle).

 

[wradman]

studying

Lots of good info here. And also, please don't view me as trying to step in as the 'expert'. I'm not. I'm not. I just like to get in and stir up the information flow, especially when I've got pictures that help clarify the topic for everyone.

In fact, I'm becoming more clear and smokechase is doing a great job and spending some really dedicated time to make sure we're all on the same page.

Even though the thread is on barberchair and we're getting more into tapered hinge and 2 dimension vs 3 dimension hinging, here's a decent picture, slightly exaggerated, but clearly showing the tapered hinge, and level (front to back) angled (side to side) backcut in all the dimensions, and the result.

The top had been taken out and normally I just block out the firewood chunks, but we had a log arch and needed the firewood at streetside, so decided to drop it and move it out in two lengths. The 30-foot trunk was a slight lean the direction I wanted it to go, non-technical, no obstacles, though the direction of fell was slightly to the left. I was showing a guy the tapered hinge and how to fell the trunk and get it to go slightly to the right.

I set up the tapered hinge so that there was zero holding wood to one side, tapering up vertically. I didn't actually intend to taper back horizontally, but when the tree started to fall, I aborted the cut. that created a 3-dimensional tapered hinge, with a mild barberchair- all the things we're discussing in one image. Had the backcut come in a bit more on the high side, we'd have had a two-dimensional tapered hinge with no barberchair.

And Clearance, on the previous picture you were exactly right. The tree was pulled too hard. I was trying a different face cut with a vertically-oriented plunge to knock out a wide face wedge. I was being too conservative in my back cut (because I had ample pulling power), resulting in a barberchair (see 'previous image' below).

I still don't think we're 100% clear, as the back cut angle can result in a hinge with it's angled dimension, which can be confused (and I read this into Ellison's reply) with the direction of the bar coming in, which can have two dimensions (bar tip up or down creating the tapered hinge, or saw body pivoted on a horizontal plane resulting in the back cut coming in at an upward or downward angle).

i'm not sure that i understand exactly what you guys are trying to accomplish,it could be due to my lack of education.
If you are you trying to make the tree swing around an object you would be just as well learning a dutchman because you are still cutting your holding wood off on one side from what i can see, Boy if i knew how to draw on this computer i could show you guys a few positive things.
There is another way to change the direction i don't know if you have heard of, here goes
say yyou want your tree to fall in the direction of 1 o'clock
-do a nice clean under cut
-pick your undercut wedge off the ground put it by your side
-start your back cut like you are going to make a perfect cut
-when the tree starts to go put your undercut wedge back in the tree on the farside(11 oclock side) into the undercut
-this will cause the wedge to squish into the undercut hole
-while the tree is on it's way over and starts to bind ,cut just a little holding wood out from behind the wooden wedge ,this will cause the tree to veer to the right on the way down.

Do not try this if you are a weekend warrior
It will give you the same result as a dutchman

 

[smokechase II]

Dutchstep

Wradman:
What you describe I have heard referred to as a Dutch block, or Dutch rock etc.
Name depends on what hunk of stuff that happens to be nearby that you use.
A simpler way of doing the same is to use a Dutch step.
You're hinge is non symmetric and is shorter on one side (this side closes first - the 11:00 side).
The big caveat to any of these Dutch guys is that any very early closing face technique is a barber chair concern. Since the Dutch step/block is not a full stop like a Dutchman, generally it should not be as high a risk.
Additionally on the Dutch block thingy; if you use a conventional undercut, you do not have to stay near the tree to place the Dutch block. A little more safety spacing from the falling event, although it is a step down for a west coast faller to use other than a Humboldt psychologically.

 

[JanThorCro]

Only the most skilled can avoid kickback when plunging in with the tip of the bar.

Plunging skillfully is not rocket science. It's a good idea to get instruction and will need practice to become skilled at it, especially when using it to avoid triggering a barber chair on forward leaners. Think of a 30 - 36" stump with about 80 - 100 plunges into it, to really develop the feel for plunging. Tim Ard refers to plunging as "A Basic Technique". If the only time I plunged was on forward leaning trees, my plunging technique would not be dialed in enough for these hazardous felling situations. I love reading your post's. Even if this one guarantees I'll continue to create the best notch apex's I can to AVOID a Dutchman. It's just outta my zip code.