Barber Chair question

[northmanlogging]

and what you don't seem to understand is that straps are a good way to get killed if it does chair.

providing a false sense of security makes people do dumb ****, namely not making proper cuts, causing a chair

 

[catbuster]

and what you don't seem to understand is that straps are a good way to get killed if it does chair.

providing a false sense of security makes people do dumb ****, namely not making proper cuts, causing a chair

+1

Straps/chains/whatever are no replacement for doing it the right way. Doing things the right way doesn’t require stuff that makes you feel safe. It just is safe, or at least the safest way to do what it is that you’re doing.

 

[046]

and what you don't seem to understand is that straps are a good way to get killed if it does chair.

providing a false sense of security makes people do dumb ****, namely not making proper cuts, causing a chair

what you don't understand is .. at no time have I stated NOT to make proper cuts.
that's like me stating .. you said bore cut is the correct cut for all leaners

a quality strap wrapped 3x-4x makes all but impossible for a smaller trunk to split
I don't have exact ft lb energy generated numbers but some folks seems to think force needed to prevent a smaller trunk from splitting is same as force generated by fall.

what is wrong with adding an extra margin of safety for folks who don't cut much?
unfortunately .. there's no way to stop stupid

 

[rwoods]

046, not trying to argue just to argue but in my humble firewood hack opinion, folks who don't cut much typically shouldn't be encouraged to cut any tree that one would consider strapping against a barber chair. I believe our logging friends' concern of lack of underlying cutting skills and concern of adding another element of danger (possibly multiplied by inexperience in both falling and strapping technique) are valid points particularly with any tree of substance. Unless it is tight and strong, a strap won't prevent a split. Whether or not it will prevent a chair is a matter of physics. Pretty much depends upon how much of a load will be placed on it. Just the leverage of a tall relatively small diameter stem can place a tremendous load on the strap. Due to the length of the ratchet mechanism and most tail straps, it takes a pretty good size tree to secure tightly with a 10,000# (3,333# WL) strap.

Ron

 

[046]

046, not trying to argue just to argue but in my humble firewood hack opinion, folks who don't cut much typically shouldn't be encouraged to cut any tree that one would consider strapping against a barber chair. I believe our logging friends' concern of lack of underlying cutting skills and concern of adding another element of danger (possibly multiplied by inexperience in both falling and strapping technique) are valid points particularly with any tree of substance. Unless it is tight and strong, a strap won't prevent a split. Whether or not it will prevent a chair is a matter of physics. Pretty much depends upon how much of a load will be placed on it. Just the leverage of a tall relatively small diameter stem can place a tremendous load on the strap. Due to the length of the ratchet mechanism and most tail straps, it takes a pretty good size tree to secure tightly with a 10,000# (3,333# WL) strap.

Ron

this why I posted up the videos that I did:

1. my guess is the person that got killed got fooled by small size of leaner
2. basics like making sure you got an escape path were ignored
3. there's no accounting for stupid and knowing when to step away

it's not by accident I posted up those videos showing proper cuts that included NO bore cuts with holding wood for trigger.
second video also shows proper cut for small leaners where there's not enough wood for a bore cut.

again .. for smaller leaners there is nothing wrong with using a good strong strap wrapped 3x-4x then proceed with proper cut
one problem is the topic of barber chair can be confusing by nature determining which cut is correct

pretty safe to say forces generated by act of falling are waaaay higher then forces generated at start of a split.
force generated by a splitting trunk is waaaay higher then force need to prevent split from starting.

fyi .. don't worry about hurting my feelings, got pretty thick skin. I've posted up 40k+ posts in last 6 months here:
https://www.arboristsite.com/community/threads/the-left-cant-meme.333232/page-2298

stay safe!

 

[catbuster]

It is *not* safe to say the forces generated by the split are much less than a falling tree.

Force equals mass times acceleration. A split accelerates much faster than 32 ft/second squared. It’s also shock loading that strap or chain, which causes the material in the strap or chain to behave differently, and usually fail. I don’t want to go deep into that, but there’s a reason chains break when shock loaded well below what their safe load is. A chair is also going to shear load a strap at an angle from where it’s at its strongest so the capacity is reduced by whatever the cosine of the angle between the tree and the strap is.

Wood, in engineering, is considered to have an ultimate tensile strength (at total failure) of around ~300 psi along the grain. On a 12” tree with a 1” hinge that tree splitting along the hinge is 3600 lbs of force. You’re already over your strap’s strength, and that’s assuming it’s tight, which isn’t possible on a small tree just because of the ratcheting mechanism. So now your strap goes flying up the tree with the split, and you’re laid out or dead because you relied on a ******* strap as a false sense of security when handling a tree instead of just taking the time to do it right.

God damn it. Just do it right. If you don’t have the false sense of security then the operator has to do it right and stay on their toes. That in and of itself is a good way to stay alive. If you don’t have the skill then just stay away and hire someone who knows how to do the job.

There’s how this works. If you want to not face that straps and chains don’t work, I guess that’s on you. But you were told otherwise.

 

[046]

It is *not* safe to say the forces generated by the split are much less than a falling tree.

Force equals mass times acceleration. A split accelerates much faster than 32 ft/second squared. It’s also shock loading that strap or chain, which causes the material in the strap or chain to behave differently, and usually fail. I don’t want to go deep into that, but there’s a reason chains break when shock loaded well below what their safe load is. A chair is also going to shear load a strap at an angle from where it’s at its strongest so the capacity is reduced by whatever the cosine of the angle between the tree and the strap is.

Wood, in engineering, is considered to have an ultimate tensile strength (at total failure) of around ~300 psi along the grain. On a 12” tree with a 1” hinge that tree splitting along the hinge is 3600 lbs of force. You’re already over your strap’s strength, and that’s assuming it’s tight, which isn’t possible on a small tree just because of the ratcheting mechanism. So now your strap goes flying up the tree with the split, and you’re laid out or dead because you relied on a ****ing strap as a false sense of security when handling a tree instead of just taking the time to do it right.

God damn it. Just do it right. If you don’t have the false sense of security then the operator has to do it right and stay on their toes. That in and of itself is a good way to stay alive. If you don’t have the skill then just stay away and hire someone who knows how to do the job.

sorry but that's just BS ... there is NO way force to prevent start of a split is any close to potential forces generated after a split gets going. same for forces generated during a fall at moment of impact

again .. at NO time have I stated straps are a substitute for making proper cut
when in actual fact .. I've already stated multiple times to strap smaller leaners 3x-4x , then make proper cut

 

[catbuster]

sorry but that's just BS ... there is NO way force to prevent start of a split is any close to potential forces generated after a split gets going. same for forces generated during a fall at moment of impact

It’s not BS. It’s physics. You’re just a ******* moron who won’t listen to people who know better.

 

[046]

It’s not BS. It’s physics. You’re just a ****ing moron who won’t listen to people who know better.

what I see is total BS .. you've completely disregarded everything I've actually posted and come up with your own version.
what is wrong with adding an extra margin of safety?
now instead of attacking the post .. you start name calling ... ha ha ha

stay safe out there!

 

[catbuster]

The only B.S I have in in civil engineering.

I quantified what you’ve been arguing and proved you wrong. Now you don’t understand, and just call it ********. It’s not. You want to know how much force a tree hits the ground with? Weigh it. W=mg. F=ma. a in that case is gravity, g. So, that 75’ 12” cedar does hit the ground with 8,500 lb force. Which is greater than the force from the split. I’ll yield you that.

But your strap is still broken or up in the tree and you’re hurt or dead. At that point it doesn’t matter.

 

[046]

The only B.S I have in in civil engineering.

I quantified what you’ve been arguing and proved you wrong. Now you don’t understand, and just call it ********. It’s not. You want to know how much force a tree hits the ground with? Weigh it. W=mg. F=ma. a in that case is gravity, g. So, that 75’ 12” cedar does hit the ground with 8,500 lb force. Which is greater than the force from the split. I’ll yield you that.

But your strap is still broken or up in the tree and you’re hurt or dead. At that point it doesn’t matter.

this is why I called BS .. my comments about strength were specifically targeted at force needed to prevent split from starting.
force generated after split gets going has NOTHING to do with amount of force needed to prevent split from starting.
your comments are valid once split gets going ...

this is why I stated from the get go to use a proper rated strap wrapped 3x-4x, cinched down that strap is not moving.
then I stated to use proper cuts .. I even posted up training videos that showed proper cuts for large and small leaners.
my motto is .. no actual evidence = BS hence why I posted up videos old as the hill in terms of media by BC gov

yes I did troll a few folks by posting up training videos that doesn't use bore cut at all ... ha ha ha

 

[northmanlogging]

what I see is total BS .. you've completely disregarded everything I've actually posted and come up with your own version.
what is wrong with adding an extra margin of safety?
now instead of attacking the post .. you start name calling ... ha ha ha

stay safe out there!

the only BS here is your own ignorance, several people, arguably with more real world experience have told you that your are in fact wrong.

this is not a matter of opinion, your just wrong and to chicken **** to admit it.

 

[catbuster]

No, you (046) don’t understand anything about materials science or the physics behind it. Barber chairs are caused by reducing the cross sectional area of something under a load. The force causing the split it already there. That strap doesn’t do anything to prevent a split.

Materials yield when they yield. The strap you’re discussing here cannot be held tight enough just by virtue of the mechanism it uses to tighten. It applies no force, or even if it does apply some, by virtue of friction/coefficients of friction, it’s not enough to prevent a split.

If there was required real world evidence for everything, there would be a whole lot of dead people and a lot of buildings would fall down. That’s why people like me have gone to school for at least four years, then have to take an eight hour pre licensure test, work for four years under a licensed engineer, then take a second eight hour licensure test. It’s not easy.

 

[046]

the only BS here is your own ignorance, several people, arguably with more real world experience have told you that your are in fact wrong.

this is not a matter of opinion, your just wrong and to chicken **** to admit it.

well for someone that ignorant ... I sure posted a crap ton of actual evident to support what I stated
you certainly are entitled to your opinion but how's about backing up how I'm wrong ... ha ha ha

so far all I've been seeing is what I didn't post ....

 

[046]

No, you (046) don’t understand anything about materials science or the physics behind it. Barber chairs are caused by reducing the cross sectional area of something under a load. The force causing the split it already there. That strap doesn’t do anything to prevent a split.

Materials yield when they yield. The strap you’re discussing here cannot be held tight enough just by virtue of the mechanism it uses to tighten. It applies no force, or even if it does apply some, by virtue of friction/coefficients of friction, it’s not enough to prevent a split.

If there was required real world evidence for everything, there would be a whole lot of dead people and a lot of buildings would fall down. That’s why people like me have gone to school for at least four years, then have to take an eight hour pre licensure test, work for four years under a licensed engineer, then take a second eight hour licensure test. It’s not easy.

well how's about showing some of that engineering expertise ... ha ha ha
instead of focusing on what I didn't state ...

 

[ArtB]

Sorry I posted that pic with the chain that initiated name calling.

FWIW the photo is from > 20 years ago, the feller was my neighbor, 83 YO at the time, he was a professional logger in the 40's and 50's and felled a few > 8 ft DF in his day that were still left here, he was happy to fell one more relatively large tree. He also was the head of King Co WA parks department in later years.
This was a black cottonwood 20 feet from buildings, so wanted zero risk. 155 ft tall BC, had died, was straight, no lean. It was also guyed from 70 feet up with 2 ea 5/8" wire ropes tied to a couple of 1000 YO DFir stumps for anchors. We parked an old car 130 feet from the tree and hit the car dead center. Think there is an old thread on felling it in the archives.
Was also easier to wrap chain on trunk vs. trying to get chain under the log after felling to drag it with dozer.

Edit PS: memory getting foggy, was only 17 years ago, my first post here!

 

[046]

Art .. thanks for being so gracious with your comments.

I'd been biting my lip for awhile not pointing out tree pic with chain was not much of a leaner.
what little lean was pointed opposite direction of fall ..

have not been active for quite sometime ... is Gypo still posting?

 

[rwoods]

046, I have three questions for you - one practical and two you may or may not know the answer - and one possible follow up question. Practical first, how do you wrap, secure and tighten three to four wraps of a strap around a small tree? Next questions: Is strapping a technique taught or approved by BC, any other governing body or recognized organization? Does any company make a purpose-built strap for the use you advocate? If either is “no”, then why not?

Ron

 

[EchoRomeoCharlie]

I've had a few ash barber chair before I really knew what I was doing. Haven't had one in quite a while now...but obviously, it can happen to anyone. The last few times i've seen chairs is because people simply leave too much hinge on leaning trees.

Leaning trees that are being felled with the lean simply don't need much hinge. The only time you need a big hinge on a leaner is if you're trying to turn it hard, and even then, the hinge should be thicker on the top side and thin on the bottom.

Leaning trees that I think will chair get super thin hinge. Half or smaller than I would leave on a normal tree. They all get plunged to set the hinge unless there's some really weird situation that doesn't allow a plunge/bore cut.

Normal trees get 10% hinge, leaning trees being felled with their lean get 5%. Leaning trees just pick up speed so much faster and doesn't give the fibers time to bend/break so a normal size hinge can still chair.

 

[046]

046, I have three questions for you - one practical and two you may or may not know the answer - and one possible follow up question. Practical first, how do you wrap, secure and tighten three to four wraps of a strap around a small tree? Next questions: Is strapping a technique taught or approved by BC, any other governing body or recognized organization? Does any company make a purpose-built strap for the use you advocate? If either is “no”, then why not?

Ron

not to be flipant .. but why don't you do you own research and answer you own questions.
then post it up for all to see ... there's nothing better than to see someone present a topic backed with actual evidence.

this topic has been around AS for quite sometime .. look how old this thread is
what's completely predictable was all the incoming crap .. ha ha ha