is this snap-cut technique acceptable?

[Plasmech]

Say I want to snap-cut a fairly large diameter branch or part of one. I'm worried about getting the saw pinched. So, I plunge cut into the branch at the desired under-cut depth and come "down" to about an inch away from the bottom. I then rev the saw and come up underneath to clip the remaining inch out. Then I back cut the "top" and away she goes.

Is this a good idea or a really, really bad one? Thanks!

 

[blewgrass]

you'll get pinched finishing your bottom cut.

 

[tree md]

Yup, I agree, a pinched saw would likely be your result. I mainly use snap cuts for chunking the spar.

 

[tree md]

For what it's worth plas, I generally refer to a snap cut as a spar cut where I make a face cut a couple inches into the tree, make a back cut until the chunk starts to sit down on my bar, then pull my saw out of the tree and break the chunk over. I refer to the cuts I make on limbs when I am trying to get a little direction or flat drop one as a compression cut. Not sure if it is the right terminology or not. I mainly use compression cuts to flat drop limbs out of habit. Not really necessary with a 200T as it will cut through the limb fast enough to drop it flat without an undercut.

 

[beastmaster]

I don't think you need to undercut it so much that you'd have to use a plunge cut. I like the snap cut when it works. Its really embarrassing to get a saw pinched doing that undercut, but it can be dangerous if the saw sticks in the downward cut and wants to go down with the branch, that sometimes happens on snap-cutting big branches if not careful.

 

[Plasmech]

I don't think you need to undercut it so much that you'd have to use a plunge cut. I like the snap cut when it works. Its really embarrassing to get a saw pinched doing that undercut, but it can be dangerous if the saw sticks in the downward cut and wants to go down with the branch, that sometimes happens on snap-cutting big branches if not careful.

I try to do a deep undercut in worry that I could get a partial barber-chair if it's too shallow.

 

[Jovary]

why not cut perpendicularly to the fall. No top cut and bottom cut, 2 side cuts that way theres enough holding wood to keep it from pinching and snapping prematurely. Then you can just shake the piece it off laterally

 

[outofmytree]

Say I want to snap-cut a fairly large diameter branch or part of one. I'm worried about getting the saw pinched. So, I plunge cut into the branch at the desired under-cut depth and come "down" to about an inch away from the bottom. I then rev the saw and come up underneath to clip the remaining inch out. Then I back cut the "top" and away she goes.

Is this a good idea or a really, really bad one? Thanks!

A snap cut, consisting of an under cut 1/3 diameter and a top cut of 2/3 diameter is either inbound or outbound. Use the inbound cut to remove branch weight without trapping your saw before finishing the branch to collar as per standards.

Hope this helps.

 

[outofmytree]

why not cut perpendicularly to the fall. No top cut and bottom cut, 2 side cuts that way theres enough holding wood to keep it from pinching and snapping prematurely. Then you can just shake the piece it off laterally

Not a good idea Jovary. Stick with under and over cuts and if the branch must be controlled rather than dropped then rig it down.

 

[SINGLE-JACK]

A while back, SherrillTree sent out a mailer that included an illustration recommending a "new" method for "snap cutting" limbs.

Apparently under certain conditions the popular method of 'by-passing' the cuts can create a notch which could pinch the chainsaw such that the saw would be trapped in the falling limb. If that should happen, it's easy to imagine the hazard to the climber (not to mention the saw) - especially if a break-away saw lanyard was not used.

So, the new recommendation showed making the bottom cut and the top cuts in-line so no notch was created to grab the saw with the falling limb.

I've asked Sherrill, on their forum, to post the illustration. I've never had a saw trapped that way but kudos (again) to Sherrill for pointing out a potential safety issue.

Anyway, beware - be safe.
Jack

 

[tree md]

A while back, SherrillTree sent out a mailer that included an illustration recommending a "new" method for "snap cutting" limbs.

Apparently under certain conditions the popular method of 'by-passing' the cuts can create a notch which could pinch the chainsaw such that the saw would be trapped in the falling limb. If that should happen, it's easy to imagine the hazard to the climber (not to mention the saw) - especially if a break-away saw lanyard was not used.

So, the new recommendation showed making the bottom cut and the top cuts in-line so no notch was created to grab the saw with the falling limb.

I've asked Sherrill, on their forum, to post the illustration. I've never had a saw trapped that way but kudos (again) to Sherrill for pointing out a potential safety issue.

Anyway, beware - be safe.
Jack

I have never had my saw caught with an outbound cut (according to outofmytree's diagram) but I have had it caught with an inbound cut. For what it's worth.

 

[treeclimber101]

A snap cut is the proper pruning cut as well . to prevent tearing the bottom of the branch collar. The snap cut is the only way I deal with trunk wood , it's safe and very manageable when dealing with a leaning tree

 

[lego1970]

I've always considered a snap cut to be when you are chunking out pieces of wood by cutting perpendicular and/or on both sides of the limb slightly overlapping the cuts. Then you put your saw away, and with a little wiggle or push with the hand, it snaps off, hence the name snap cut. That only works on pieces that you can handle, but it allows you to throw the piece any where you want. Otherwise if I'm just dropping a limb I make an undercut, then the top cut a couple inches out. If it's a big limb, then I make the top cut directly over the undercut so the bar doesn't get caught in the kerf, (which I've seen a guy loose his saw that way). I never really considered cutting it that way to have a name, just that's the way you do it, so you don't peel off the bottom. I always thought if you reverse the cuts, make a undercut then make the top cut a couple inches in, it was considered a jump cut but I've never messed with that, so I'm not sure about the jump cut stuff. Then there is the hinge cut where you just slowly make a top cut. That's how I've always interpet it, and only called a snap cut where you snap the branch with two perpendicular cuts. I'm not saying I'm right, I'm just saying that's how I've always made my cuts (depending on branch size, type of tree, etc, etc.) and how I've called it.

 

[capetrees]

A snap cut, consisting of an under cut 1/3 diameter and a top cut of 2/3 diameter is either inbound or outbound. Use the inbound cut to remove branch weight without trapping your saw before finishing the branch to collar as per standards.

Hope this helps.

I always use the outbound snapcut as described but make the undercut first and back from the overcut by 3-4". That way the branch won't strip out the bark underneath and a clean flush cut follows after the branch drops. Avoid the pinch by cutting the underside first.

 

[beastmaster]

I have always used the in-bound cut, but I think I'll try the out-bound cut the next time I need a snap cut if it decreases the chance of it grabbing the saw. Doing your top cut over your undercut as recommended by sherrill, I wonder if you'd still get that snap effect? The 1/3 undercut rule can't always be done if the branch is really long with lot of end weight( I,m thinking coulter pine) I some time use a narrow wedge for my bottom cut on really large long branches with lots of end weight .

 

[Jovary]

Not a good idea Jovary. Stick with under and over cuts and if the branch must be controlled rather than dropped then rig it down.

Why is this no good? This is what I've always referred to as a snap-cut. Maybe my definition is wrong but its seems Lego is talking about the same way. I'm not suggesting this is the only way, but it definitely has its place. Obviously you can't always cut at the 90 degrees but the more vertical it is the less chance it will hinge and snap on its own. I find that if i have a 4 foot stub that is tossable and I have a safe target this is the best method.

 

[randyg]

why not cut perpendicularly to the fall. No top cut and bottom cut, 2 side cuts that way theres enough holding wood to keep it from pinching and snapping prematurely. Then you can just shake the piece it off laterally

This works very well, but not usually for an entire limb. The more vertical the limb, the better it works.

I think Plas is talking about either entire or large part of "larger" diameter horizontal limbs.

Now I know that the MS200T is about "THE MOST POWERFUL TOP HANDLE SAW KNOWN TO MAN" but it still can NOT out cut the barber split on larger dia. say 10" and up limbs most of the time.

If you don't want to call up a bigger saw just yet, here is a way to pull it off with that top handle. On 10" dia. limb, under cut around 3 inches. (Sometimes I will cut 2 inches and then quickly drop the bar out of the cut. If the end of the limb holds steady, I'll get back in the kerf and get another half inch and then drop back out again, checking the limb for movement. Once the tip drops a bit, stay out of that undercut or you WILL get stuck) Then go directly above that undercut with a plunge cut, leaving an inch or two of wood between cuts, and also leaving that last 2 inches or so on the top. (You now have tension on that top strap, and compression on the bottom strip.) At full RPMs, cut from the top down. The top strap will pop, and about the time your saw hits that bottom strip, compression wood turns into tension and with very little cutting it too will pop. Bit of an adrenaline rush the first couple times you get this to work right. Good cut to have in the 'bag of tricks'.

Don't try this with a dull or loose chain.

ENJOY!

randy

 

[outofmytree]

Why is this no good? This is what I've always referred to as a snap-cut. Maybe my definition is wrong but its seems Lego is talking about the same way. I'm not suggesting this is the only way, but it definitely has its place. Obviously you can't always cut at the 90 degrees but the more vertical it is the less chance it will hinge and snap on its own. I find that if i have a 4 foot stub that is tossable and I have a safe target this is the best method.

Assuming we are talking about a horizontal limb like the ones I drew previously, vertical cuts on this sort of limb create a vertical hinge. Firstly this hinge will either close toward or away from you and can easily pinch your chainsaw bar. Secondly if you successfully join the two cuts and the branch does break you have a much greater chance of bark tearing inward towards the trunk as the action will be more a tearing away rather than snapping. Thirdly it is much more difficult to make vertical cuts on horizontal branches and still keep the saw between your shoulder and your knee where you are strongest and safest.

I hope this answers your questions Jovary.

 

[Plasmech]

This works very well, but not usually for an entire limb. The more vertical the limb, the better it works.

I think Plas is talking about either entire or large part of "larger" diameter horizontal limbs.

Now I know that the MS200T is about "THE MOST POWERFUL TOP HANDLE SAW KNOWN TO MAN" but it still can NOT out cut the barber split on larger dia. say 10" and up limbs most of the time.

If you don't want to call up a bigger saw just yet, here is a way to pull it off with that top handle. On 10" dia. limb, under cut around 3 inches. (Sometimes I will cut 2 inches and then quickly drop the bar out of the cut. If the end of the limb holds steady, I'll get back in the kerf and get another half inch and then drop back out again, checking the limb for movement. Once the tip drops a bit, stay out of that undercut or you WILL get stuck) Then go directly above that undercut with a plunge cut, leaving an inch or two of wood between cuts, and also leaving that last 2 inches or so on the top. (You now have tension on that top strap, and compression on the bottom strip.) At full RPMs, cut from the top down. The top strap will pop, and about the time your saw hits that bottom strip, compression wood turns into tension and with very little cutting it too will pop. Bit of an adrenaline rush the first couple times you get this to work right. Good cut to have in the 'bag of tricks'.

Don't try this with a dull or loose chain.

ENJOY!

randy

Thanks for all the replies guys. Yes Randy, I was talking about let's say for example a 12" diameter branch shooting off at a 90ish degree angle to a very large tree. Lot of wood, lot of forces to recon with.

 

[outofmytree]

I have always used the in-bound cut, but I think I'll try the out-bound cut the next time I need a snap cut if it decreases the chance of it grabbing the saw.

Taking aside personal experience for a moment, the reason an inbound cut reduces the risk of having the branch take your saw is that should the gap between cuts be too large then the branch MAY break as shown below on an outbound cut.

The issue is the gap between cuts. Keep this gap say less than 1/10th the branch diameter and gravity will do the work for you.

IMO if you are removing branches of 12" diameter or more then a scarf on the lower side is a better choice than a step cut. Even a wedge of 15 degrees will give you more control over fall and ensure you have time to remove the saw before it can become stuck.