1/3 Diameter Notch Rule

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RES

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I have always wondered why the manuals tell you to make the felling notch 1/3 the diameter of the tree and not more. When you make the notch the weight of tree above the notch is supported by the uncut lower portion. Therefore an overturning moment is created to cause the tree to fall towards the notch. When you begin cutting the opposite side and reach 1/3 that overturning moment no longer exists. From that point on the moment begins to turn the tree back towards the cutting side. It would seem to me that it would be better to make the notch 1/2 the diameter to avoid this from happening. The 1/3 notch seems to work. The only explanation that I would have is that when you make the notch, the overturning moment causes the flexible tree to shift its weight towards the notch. This is enough to cause the tree to fall towards the notch, even though the back cut is bigger.
 
RES said:
I have always wondered why the manuals tell you to make the felling notch 1/3 the diameter of the tree and not more. When you make the notch the weight of tree above the notch is supported by the uncut lower portion. Therefore an overturning moment is created to cause the tree to fall towards the notch. When you begin cutting the opposite side and reach 1/3 that overturning moment no longer exists. From that point on the moment begins to turn the tree back towards the cutting side. It would seem to me that it would be better to make the notch 1/2 the diameter to avoid this from happening. The 1/3 notch seems to work. The only explanation that I would have is that when you make the notch, the overturning moment causes the flexible tree to shift its weight towards the notch. This is enough to cause the tree to fall towards the notch, even though the back cut is bigger.
Click to expand...

Bugger me, dont they teach you ANYTHING over there! And they let you use saws. :mad:
 
On a big tree in the wind I cut the notch way in over halfway even, then catch the rocking tree with a quick backcut, talking in the bush not in town
 
Cutting a face 1/3 the diameter of the tree is a safe guideline for the trees most people will be falling. It is not written in stone and changed as conditions warrant. For me when cutting "larger" trees, say 4' DBH I will face the tree less than 1/3 the diameter. I always place a wedge and keep it snug and "never" cut through the hinge. BTW I am talking about firs, pines, redwoods, etc. Snags may require a deeper face, maybe a more open face then normal.

A shallow face, a wedge, and a sharp chain with a powerful saw means the tree is unlikely to barberchair and less of a change to lift the root plate and the tree will jump off the stump and move away from me. Sometimes I don't want the tree to jump so I use a deeper open face. A good hinge means good directional control and a higher stumpshot will help the tree from coming back at me esp on flat ground.

Use what works for you as long as it is safe.
 
Haywire Haywood said:
If sarcasm is no longer allowed on AS then Darren might as well shut the site down now.

Ian
Click to expand...

Sarcasm is a wonderful thing.

Not helping someone who CLEARLY could use some helpful advice is another, when it comes from a self proclaimed genius in the Arborist field.
 
IchWarriorMkII said:
Sarcasm is a wonderful thing.

Not helping someone who CLEARLY could use some helpful advice is another, when it comes from a self proclaimed genius in the Arborist field.
Click to expand...

Yup...gotta agree. Ekka, with his experience and knowledge, could have helped this guy. Instead, he chose to display his immaturity and shameful lack of humanity.

Hey Ekka...if the guy has a legitimate question, why not just answer it? If he argues with you or rejects your advice or turns out to be a cretin then you can whack him around a bit. Until then let's give him the benefit of the doubt. :cheers:
 
Ekka said:
Geee, what about if it's windy and raining? Maybe go a bit more eh. :chainsaw:
Click to expand...

Geeee? Nah if it's raining AND windy you get wet then go home. As far as 1/3 notches, they're fine, but 1/2 way through makes no difference and I've seen many a strutting know-all out in the bush pissing their pants and wringing their hands over trivial crap. Give them a few weeks of felling hillsides every day - they soon learn to keep their 'expert' opinions to themselves....
 
RES said:
I have always wondered why the manuals tell you to make the felling notch 1/3 the diameter of the tree and not more. When you make the notch the weight of tree above the notch is supported by the uncut lower portion. Therefore an overturning moment is created to cause the tree to fall towards the notch. When you begin cutting the opposite side and reach 1/3 that overturning moment no longer exists. From that point on the moment begins to turn the tree back towards the cutting side. It would seem to me that it would be better to make the notch 1/2 the diameter to avoid this from happening. The 1/3 notch seems to work. The only explanation that I would have is that when you make the notch, the overturning moment causes the flexible tree to shift its weight towards the notch. This is enough to cause the tree to fall towards the notch, even though the back cut is bigger.
Click to expand...


I see your point, but the answer is Wedges....!!!! :givebeer: :givebeer:
 
Last edited:
Gologit said:
Yup...gotta agree. Ekka, with his experience and knowledge, could have helped this guy. Instead, he chose to display his immaturity and shameful lack of humanity.

Hey Ekka...if the guy has a legitimate question, why not just answer it? If he argues with you or rejects your advice or turns out to be a cretin then you can whack him around a bit. Until then let's give him the benefit of the doubt. :cheers:
Click to expand...

For real...
 
notches.......

I'm sorry but only 1/4-1/5 of the way in the tree for a notch for me. I've even had really good luck with 1/6 of the way in.......:clap: :) :cheers: :greenchainsaw: :givebeer: :chainsaw:
 
1/3 is a good place to start (rule of thumb). There are a lot of different reasons to use different depths, undercut's, boring, etc. etc. etc.
When I'm training a new guy on my crew, I tell them; Untill you master the basics, stick with the basics.

1/3 is a good rule of thumb, but not carved in stone.

Andy
 
Heck, I even know of bigger geniuses that dont even use or need a notch ... they just back cut, rain hail or shine. LOL :greenchainsaw:
 
Two reasons for trimming off buttresses:

Make the cross section smaller, and easier to cut when the bar length isn't sufficient to make the cut in one pass.

Create a more symmetric shaped log for the mill.

No one directly answered the original question, which assumed a perfectly balanced tree. In such a case, a deep face would undermine the center of balance and allow the tree to fall on its own. This technique isn't a good idea for most trees, as it removes so much wood, making gunnning corrections next to impossible. As stated a few times, I do this when aloft, and cutting vertical sections with no target behind the felling direction. Let the wood weight bring her over by itself.
 
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