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I suspect there was a fair chunk of holding strap there, he just powered through it pretty fast and got the heck out of there ;)

You do have to sorta judge how much you can leave depending on the tree and how much tension you have to deal with.

At a demo I attended, a Husky Rep demonstrated the 80/10/10 rule for the notch, hinge and back strap. Cut the notch so the width is about 80% of the diameter, make your borecut and leave a hinge about 10% of the diameter and a backstrap about 10% of the diameter. For a 20" tree, the notch would be about 16" wide and about 4" deep, Hinge about 2" wide and a 2" strap. The bored area would be about 12" wide.
Of course, there are many variables that must be considered as stated in this thread.
 
On a 12" tree, is there really enough room for a notch, bore cut, and trigger? Bar + chain on my 460 is about 41/4". Doesn't leave much room for error. Maybe I just need to use a smaller saw. I really like the idea of boring out the center on small diameter trees.

Another quick word from personal (bad) experience, once again I share my idiocy. In my earlier days I lost the hood on a beautiful 1958 Fergusen tractor when I parked it too close to the high side of a 30" red oak with a strong lean. (1.) I blasted through the hinge in my over-zealous attempt to prevent barber chair (2.) there was a trumpet vine high in the canopy that I did not see, under tension, tieing the top of the red oak to a previously felled tree on the other side of the tractor. That @$#*&% red oak did a 180 degree pirouette that would have made a ballerina proud. Overconfidence kills.
 
At a demo I attended, a Husky Rep demonstrated the 80/10/10 rule ........ For a 20" tree, the notch would be about 16" wide and about 4" deep, Hinge about 2" wide and a 2" strap.

Thats sounds about right. I have found you can use a shallower notch than normal, it really only has to be deep enough to form a decent hinge, so 1/5 of the tree diameter would be fine.

So with smaller trees (12") you can still use it, just make a real shallow notch (2" deep?) leaving enough space to do your bore cut.

Cheers

Ian
 
Thats sounds about right. I have found you can use a shallower notch than normal, it really only has to be deep enough to form a decent hinge, so 1/5 of the tree diameter would be fine.

So with smaller trees (12") you can still use it, just make a real shallow notch (2" deep?) leaving enough space to do your bore cut.

Cheers

Ian

Right on Ian. Following the 80/10/10 formula, on a 12" tree the notch would only be about 1 1/2" deep (9.6" wide), hinge and strap would be about 1 1/4" thick. That leaves about 8" for the bore. Definitely requires some good saw control, but doable. You would want a nicely balanced saw for this in order to get both cuts level and at the same plane. As was stated earlier, I would practice on some non-threatening trees first until one is confident.
 
80 10 10

On the West Coast we seldom see that 80% face rule of thumb. Honestly, I've never heard of it outside of the internet or open face felling materials.

With larger timber we emphasize face depth. The general rule here is 1/3rd in.

Granted, this gets fairly complex with all the possibilities, but our main focus is getting more of the weight of the tree on the side of the hinge that is in the direction of fall. Making it easier to wedge. Overall, with smaller timber or dead (lighter) trees this may not be as important.
On this coast, with steeper ground and more remote settings, fallers are better with wedges and jacks. They can't depend on a piece of equipment pushing over a tree.

Mostly, a cutter has to understand the potential need for either thought process and be ready to adjust face depth. The big thing I'd suggest is to make sure and label any of these GENERAL rules.

A classic example is dropping a short but very large diameter 'staub' or 'short stubby'. When confronted with a broken off green tree that is say; 20 feet tall and 5 plus feet in diameter. The other general rules are thrown out and the face depth is 50% in. Resulting in a hinge that is 100% the width of the tree.
Put this on a sliding scale with trees that are similar but part way back to a tall straight guy and you can see how adjusting hinge depth depending on your situation can be beneficial.

All the Best
 
On the West Coast we seldom see that 80% face rule of thumb. Honestly, I've never heard of it outside of the internet or open face felling materials.

With larger timber we emphasize face depth. The general rule here is 1/3rd in.

Granted, this gets fairly complex with all the possibilities, but our main focus is getting more of the weight of the tree on the side of the hinge that is in the direction of fall. Making it easier to wedge. Overall, with smaller timber or dead (lighter) trees this may not be as important.
On this coast, with steeper ground and more remote settings, fallers are better with wedges and jacks. They can't depend on a piece of equipment pushing over a tree.

Mostly, a cutter has to understand the potential need for either thought process and be ready to adjust face depth. The big thing I'd suggest is to make sure and label any of these GENERAL rules.

A classic example is dropping a short but very large diameter 'staub' or 'short stubby'. When confronted with a broken off green tree that is say; 20 feet tall and 5 plus feet in diameter. The other general rules are thrown out and the face depth is 50% in. Resulting in a hinge that is 100% the width of the tree.
Put this on a sliding scale with trees that are similar but part way back to a tall straight guy and you can see how adjusting hinge depth depending on your situation can be beneficial.

All the Best

Smokechase - makes sense. Does the size of those big NW trees reduce the potential for barberchairs?
 
On the West Coast we seldom see that 80% face rule of thumb. Honestly, I've never heard of it outside of the internet or open face felling materials.

With larger timber we emphasize face depth. The general rule here is 1/3rd in.

Granted, this gets fairly complex with all the possibilities, but our main focus is getting more of the weight of the tree on the side of the hinge that is in the direction of fall. Making it easier to wedge. Overall, with smaller timber or dead (lighter) trees this may not be as important.
On this coast, with steeper ground and more remote settings, fallers are better with wedges and jacks. They can't depend on a piece of equipment pushing over a tree.

Mostly, a cutter has to understand the potential need for either thought process and be ready to adjust face depth. The big thing I'd suggest is to make sure and label any of these GENERAL rules.

A classic example is dropping a short but very large diameter 'staub' or 'short stubby'. When confronted with a broken off green tree that is say; 20 feet tall and 5 plus feet in diameter. The other general rules are thrown out and the face depth is 50% in. Resulting in a hinge that is 100% the width of the tree.
Put this on a sliding scale with trees that are similar but part way back to a tall straight guy and you can see how adjusting hinge depth depending on your situation can be beneficial.

All the Best

Good post Smokechase - makes sense. Does the size of those big NW trees reduce the potential for barberchairs?
 
Thanks, all. I'm still learning that I don't even know how much I don't know. This is a great forum.
 
Great discussion!

My rules of thumb are similar. But mainly i watch 2 things specifically to determine exactly how hard to apply these standards.

1) is to undermine beyond the Center of Gravity well enough to a)want to fall in chosen direction + b)flex the fiber of hinge to do so Also asses how high CG is from proposed hinge pivot height.

2)Bring the back of the back of the hinge to the approximate widest part of the tree; especially on the control/anti-lean side for best leverage against sidelean or side pushes during fall (from other obstacles in path).

No. 1 is generally preset for you; lean away from hinge; hopefully fairly in falling direction. But covers the short/stubby extreme example by SmokeChaser too. If you can't bring the hinge pivot back far enough to accomplish this; you must either push or pull.

No. 2 Takes into consideration sidelean control needs and non-perfectly round stumps, rotted areas etc. i always face tree; then inspect face for decay and dryness. Decay is bad/bad. Dry/dead/ frozen wood can still push; but is less helpful for tension/pull; being less elastic. Both push and pull is needed in hinge/face machine. So i assess where tension and compression wood is needed; and if the face shows that type of condition possible in those specific positions. And dead and decayed are 2 different categories.

i believe in push (mostly by wedge) and pull (mostly by rope) to force a stronger hinge; just relieve these added forces when tree starts to move. Forces at FirstFolding(i define this time period as done when the tree will travel on it's own) determine hinge strength; more force forces hinge stronger. Hinge strength just being a reflection of the forces on it at this point in time; so we 'fake it out', to 'think' it has a bigger tree to steer! Additional forces after FirstFolding tax the previously set strength of the hinge; so essentially weaken it; so we relieve them. This is one thing a wedge works for us automatically; when the tree lifts, the wedge stops pushing.

i think the slanted BackCut is a no-no; in that the 'back stop' is weaker in case of sit back. If the tree sits back against a slanted back stop; the immense leveraged force goes more across the column of the stump/ rather than served down into the strength of the column. Also, there is weaker backstop to push off with wedge if needed for the same reason; and the wedge is pushing more straight ahead to bring tree straight ahead. But in a straight backcut with wedge pounded in, the wedge lifts, to serve forward. So the former is more of a linear applied force, whereby the latter is more leveraged arc; taking a longer route to achieve same result/direction factor. Another consideration in wedging is that the farther back the hinge; the less leveraged distance wedge has from it's lift position to the pivot of the hinge.

i might have slanted the backcut on one of them trees; to not cut into another tree behind it. and still have hinge leverage/height where i wanted; if it was safer like that.

In good wood/up to the task, i prefer to let the hinge steer mostly; and apply all additional / hinge strength increasing forces(rope and wedge) to the gunned face/ center. If pulling with line or pushing with wedge to steer; then we are unloading the hinge from it's task some. i'd rather force the hinge stronger, then taper the hinge to steer; so that my exerted additional forces go through another multiplier (hinge); instead of unloading hinge from imbalance, and replacing it with my effort; allow the mechanics to work for you.

Works great in-tree too; especially if you kerf dutch the sidelean or push from side(not full face) to work in concert with the extra pull of tapered hinge. Then, we have a pull and push in same direction and rotational, with counter pull/pushes dropped out of the equation (when kerf closes and tapered doesn't).
 
Great discussion!

My rules of thumb are similar. But mainly i watch 2 things specifically to determine exactly how hard to apply these standards.

1) is to undermine beyond the Center of Gravity well enough to a)want to fall in chosen direction + b)flex the fiber of hinge to do so Also asses how high CG is from proposed hinge pivot height.

2)Bring the back of the back of the hinge to the approximate widest part of the tree; especially on the control/anti-lean side for best leverage against sidelean or side pushes during fall (from other obstacles in path).

No. 1 is generally preset for you; lean away from hinge; hopefully fairly in falling direction. But covers the short/stubby extreme example by SmokeChaser too. If you can't bring the hinge pivot back far enough to accomplish this; you must either push or pull.

No. 2 Takes into consideration sidelean control needs and non-perfectly round stumps, rotted areas etc. i always face tree; then inspect face for decay and dryness. Decay is bad/bad. Dry/dead/ frozen wood can still push; but is less helpful for tension/pull; being less elastic. Both push and pull is needed in hinge/face machine. So i assess where tension and compression wood is needed; and if the face shows that type of condition possible in those specific positions. And dead and decayed are 2 different categories.

i believe in push (mostly by wedge) and pull (mostly by rope) to force a stronger hinge; just relieve these added forces when tree starts to move. Forces at FirstFolding(i define this time period as done when the tree will travel on it's own) determine hinge strength; more force forces hinge stronger. Hinge strength just being a reflection of the forces on it at this point in time; so we 'fake it out', to 'think' it has a bigger tree to steer! Additional forces after FirstFolding tax the previously set strength of the hinge; so essentially weaken it; so we relieve them. This is one thing a wedge works for us automatically; when the tree lifts, the wedge stops pushing.

i think the slanted BackCut is a no-no; in that the 'back stop' is weaker in case of sit back. If the tree sits back against a slanted back stop; the immense leveraged force goes more across the column of the stump/ rather than served down into the strength of the column. Also, there is weaker backstop to push off with wedge if needed for the same reason; and the wedge is pushing more straight ahead to bring tree straight ahead. But in a straight backcut with wedge pounded in, the wedge lifts, to serve forward. So the former is more of a linear applied force, whereby the latter is more leveraged arc; taking a longer route to achieve same result/direction factor. Another consideration in wedging is that the farther back the hinge; the less leveraged distance wedge has from it's lift position to the pivot of the hinge.

i might have slanted the backcut on one of them trees; to not cut into another tree behind it. and still have hinge leverage/height where i wanted; if it was safer like that.

In good wood/up to the task, i prefer to let the hinge steer mostly; and apply all additional / hinge strength increasing forces(rope and wedge) to the gunned face/ center. If pulling with line or pushing with wedge to steer; then we are unloading the hinge from it's task some. i'd rather force the hinge stronger, then taper the hinge to steer; so that my exerted additional forces go through another multiplier (hinge); instead of unloading hinge from imbalance, and replacing it with my effort; allow the mechanics to work for you.

Works great in-tree too; especially if you kerf dutch the sidelean or push from side(not full face) to work in concert with the extra pull of tapered hinge. Then, we have a pull and push in same direction and rotational, with counter pull/pushes dropped out of the equation (when kerf closes and tapered doesn't).


Thanks TreeSpyder, that's what I was trying to say! LOLOL Great details!
 
worse

Buzz:

A tree that weighs more or is taller would impart more force to contribute to a barber chair than a one with less force. I.e., one with less weight/height.

Generally, taller or bigger diameter timber should have more barber chair potential.

Then again, you could be cutting a 40"+ hardwood that has a significant lean, or a 10" Ash (Ash gets mentioned a lot in barber chair discussions), with the same basic M.O. and need to be very cautious.

The height/weight things will be overshadowed by certain species characteristics. If local pro cutters say that Ash, Doug Fir, ________ and ________ are the worst. Pay attention and be ready to say no to any tree you're not comfortable with or think thinner hinge or center face bore etc.
 
Buzz:

A tree that weighs more or is taller would impart more force to contribute to a barber chair than a one with less force. I.e., one with less weight/height.

Generally, taller or bigger diameter timber should have more barber chair potential.

Then again, you could be cutting a 40"+ hardwood that has a significant lean, or a 10" Ash (Ash gets mentioned a lot in barber chair discussions), with the same basic M.O. and need to be very cautious.

The height/weight things will be overshadowed by certain species characteristics. If local pro cutters say that Ash, Doug Fir, ________ and ________ are the worst. Pay attention and be ready to say no to any tree you're not comfortable with or think thinner hinge or center face bore etc.

Thanks Smoke. Yep - Ash was my first and only barber chair - before I found this site. About a 24" dbh with about 20 deg lean. What about wrapping the tree with several loops of heavy chain or cable and draw it tight with a chain binder? Of course, the size of the tree would limit this appication. Maybe a hazard with the chain breaking?
 
What about wrapping the tree with several loops of heavy chain or cable and draw it tight with a chain binder?

buzz sawyer, this does work well under certain conditions and it definitely eases ones apprehension, at least for me. I'll use a few wraps of bull rope when falling the top out of a heavy leaner, especially alder and maple, just be prepared for a bit of a ride; if possible it's better to climb higher. I also use this on the butt stick - when bucking down large alder with a heavy lean I'll often throw a few wraps of old 1/2" climbing rope below my cut. I leave enough slack to slide it down easily, but tight enough so that if the wood splits it won't fill the space between me and the tree. Seen a few people get pinned this way, on the worst one I had to climb up, wrap the top and help loosen his lanyard. He had some good bruises, but could have suffocated.

As for working on the ground - great stuff already posted.
 
So SmokeChase.....how long did it take ya to saw thru those trees with that swiss army knif (sawblade) :hmm3grin2orange:

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i've used load webbing strap tie downs for binding. But really shouldn't drag them out hard from under load(or any other sling, cable etc.; but i figure non-metals more sensitive to this issue) so need to plot where they will fall and have strategy for them not to be pinched where you have to pull hard to get them out. Get them extra tight by tightening as far as possible, then try to hold tension best ya can and pull slack out, then retighten. Because like a come along or winch (non-capstan); the fuller the drum the less leverage you have(as opposed to capstans, rope Maasdam, chain hoist etc. as leveraged power source). Can also tap a wedge under the strap for more tension; starting at some imperfection offering clearance to start.

Especially on longitudinal cracks, deformed, hollow, codoms and trees that splinter easy etc. Sometimes 1 above the hinge on crack etc. and 1 below. In tree on small stuff; i'll roundturn lanyard around under hinge and lean back to give firming compression to the spar. Also as ballast to loading forces of rigging; sometimes dropping back to impact force as ballast in timing to load hitting line on opposite side of spar. The choke on load and the load pulling down on choke under hinge can also firm both some. So much so as to crush some hollow loads, so will give a series of half hitches on load to catch pieces and spread out forces. A similar gauntlet of slings and krab sets will catch pieces, but not firm wood, nor spread out forces except at lead and anchor positions.

Fine discussion; i'm not the picture police or nothing; but i'd like to suggest posting smaller pix, especially embedded in the post. This makes them easier to view and faster to download. A few pictures or large ones embedded in a post makes it hard on especially our brethren on dial-ups.

In Microsoft Freebie PowerToys is a lil'widget that is for picture resizing. It is great; it puts a picture resize button on the right click menu of a picture. Even if several are selected(doing a group resize). This can also be done by other utilities or manually in an editor, but the Power Toys resizer on the click menu is really handy and quick.

This is same pic, that doesn't stretch page and 1/4 the file size, made in a few seconds. Resizer will do any size, but this is one of the defaults. On other forums stretching the page with a wide picture makes the whole thread wider, and so you have to chase text on each post on that page with horizontal scrollbar.

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speedy knife

SRT-Tech:

Is there a possibilty that cutting with the knife, using a little better technique, might have gone faster?
Just kidding.

Once again; TSI (Timber Stump Investigators) needs to inspect these.
 
What about falling a leaner off its lean

Anybody heard of this before. falling a leaner 20 to 45 degrees off the head lean to slow the trees descent rate so you can saw and keep up with the cut. I figured most hand fallers using crosscuts rarely fell trees with the lean because they could not cut fast enough to keep up with the trees rate of falling so they threw their trees off the the side of the lean. You will still have to compensate for the side lean but worth some consideration if you have the room. Also there was a comment about barberchairs being the fallers fault most of the time I disagree because i have had it happen to me during a falling of a smaller red fir 14" that had no lean and no visible cracks. This was the only time I have ever had a surprise barberchair like that and I can only figure it was because of an hidden internal defect (Ring Shake) that I could not have known about because it was internal. The only time i have seen a large 6ft Doug fir chair was because the cutter could not cut up the back cut fast enough and got scared and ran away when the backcut was still only half way competed so this large tree just ripped up vertically and fell off the side away from the escape route but shook up the cutter:eek: . This one was definitely operator error but the first one was not.
 
No, I haven't heard of that technique, but yes I can see there is some logic too it. Falling at an angle to the lean with a tapered hinge would probably reduce the barberchair potential

As for the 'fallers fault', well it was the way you cut the tree. OK, there was no way you could have known about the internal shake. If you had X-ray vision you might have cut the tree different. But yes, sometimes things happen that we cant reasonably predict :(

got scared and ran away when the backcut was still only half way competed so this large tree just ripped up vertically and fell off the side
Sometimes running away ISN'T a dumb idea :laugh:

Cheers

Ian
 
My In-Laws

Loggers as In-laws. There you go.

Their barber chair avoidance technique for many years was to have a sharp saw. If you ran away you were not just weak, you were causing the barber chair. {The Yoder Mill opened around 110 years ago in Yoder Oregon and it is still run by Yoder boys.} When that tree is popping, wanting to 'chair, keep cutting hard and you'll be fine. (They're from a serious Mennonite background, so no cussing with only occasional exceptions currently). Outside of the cross-cut era, they never had a problem with this and believe it or not, power cutting was common in the West.

For heavens sake, don't set this as your standard method. This is really foolish compared to plunge cutting the back.

However, there is the thought that if you are cutting and your tree starts to split and you feel those surprise pops. You might want to cut rather than run.
Just a thought.

Photo of a face center bore near the stumps from above.
 
Anybody heard of this before. falling a leaner 20 to 45 degrees off the head lean to slow the trees descent rate so you can saw and keep up with the cut.
Yes I have heard/ been taught this technique to help mitigate the chance of a barber. You probably wouldn't want to try to turn a real heavy leaner 45 degrees off it's lean. What you're doing with this technique is taking some of the tension off of the sap wood and putting it into the hinge. You have to consider how you will have to adjust the hinge to keep the hinge from ripping off the stump(thicker). With this technique as any other I always advise a cutter to get rid of the sap wood before continuing with the back cut(triangle cut). Here in the west I don't hardly ever see a boring back cut.
 

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