Starting plunge cuts?

[turnkey4099]

I have only done that a couple of times - none very successfully. I always got chatter and kickbacks.

What is the technique for getting a clean start? The reason I am asking is I have several big leaners to clean out in the my current working patch. I'd like to do it right vice my botched attempts in the past.

Harry K

 

[timberwolf]

Only a bit of praactice on this myself, but sharp chain firm grip and full throttle.

 

[clearance]

Thats right, sharp saw, good grip. Use the down side of the tip, start the cut towards the holding wood and cut back to where you will start the backcut, push the saw in till it comes out the other side, do not cut off to much of the holding wood or the saw will be pinched. When you have the saw buried, if kickback occurs (which it usually does a little bit) it is safer. Seeing as there is potential for barberchairs falling leaners it is really important to cut two escape paths away from where you figure the tree will slab, should it chair. I usually cut a triangle (making the backcut a triangle, I mean making the holding wood as the base of the triangle) the side away from me first, then the side closest, then I finish it at full throttle, looking up, dogs in, often with one hand so I can run away quick. Check check and check again, are my paths free? Is my saw full? Is my undercut clean?

 

[KarlP]

I have only done that a couple of times - none very successfully. I always got chatter and kickbacks.

What kind of chain have you been using?

 

[John Ellison]

Clearance has it right. Describing a verticle plunge cut. Wide open, push the tip of the bar into the wood usinging ONLY the lower half of the tip. Push down, not forward until the tip is buried then gradually change directions to forward. If you stop and then start again, you have to go from downward motion to forward motion again. If it goes to bucking you have to go to more of a downward cut until it smothes out, then forward.

 

[JimL]

and old diagram i made

 

[12guns]

I'm no pro like many of these guys, but RPM's are a must! also as much control as possible when the saw contacts the wood. Also, slow down a bit and think about what you're doing and make sure your left hand is in the correct position to trip the chain brake...Very important, and yes, the brake works well...well enough i thought i had broken my saw one time...yeah, real embarrassing.

 

[tawilson]

Maybe it's me, but it doesn't seem like I push the bar straight through like in the drawing. I guess it's because of the direction of the chain going around the tip of the bar forces the cut back and I have to angle the saw to keep the cut going straight through the tree. That makes sense in my head, I just need to talk gooder. Maybe I'll draw something.

 

[tawilson]

I be talking about number 7, the one that looks like pacman.

 

[Tonka56]

Thats right, sharp saw, good grip. Use the down side of the tip, start the cut towards the holding wood and cut back to where you will start the backcut, push the saw in till it comes out the other side, do not cut off to much of the holding wood or the saw will be pinched. When you have the saw buried, if kickback occurs (which it usually does a little bit) it is safer. Seeing as there is potential for barberchairs falling leaners it is really important to cut two escape paths away from where you figure the tree will slab, should it chair. I usually cut a triangle (making the backcut a triangle, I mean making the holding wood as the base of the triangle) the side away from me first, then the side closest, then I finish it at full throttle, looking up, dogs in, often with one hand so I can run away quick. Check check and check again, are my paths free? Is my saw full? Is my undercut clean?

Man, I'm just too dumb to actually imagine what you are describing.

 

[toolfreak]

I have only done that a couple of times - none very successfully. I always got chatter and kickbacks.

What is the technique for getting a clean start? The reason I am asking is I have several big leaners to clean out in the my current working patch. I'd like to do it right vice my botched attempts in the past.

Harry K

The diagram that JimL has posted is what I have always done. Seems to be the most controlled.

 

[turnkey4099]

I be talking about number 7, the one that looks like pacman.

Thanks to you and everybody else. It looks like my problem was in starting rather 'trying to start') the cut too high on the nose. That diagram is saved and will be referred to for refreshers a couple times.

Things are drying out up here in E Wa. Will be hitting the wood patch soon and I'll be into those leaners right off. No easy stuff to start the season and get back into working mode after sitting on my fundament all winter.

One further real dumb question. How do you line up your plunges when you have to work from both sides? Or does it even matter as long as they overlap? The ones I am working on are 3' plus and my "big" saw is only a 041 with 24" bar. Plenty of saw after they are on the ground but somewhat lacking for falling.

Harry K

 

[Patrick62]

waka, waka, waka, waka, waka, waka, , bleep bleep.

I be talking about number 7, the one that looks like pacman.

I have only plunge cut stuff that was going to pinch on the ground.
I should learn how to drop one that way. Someday. I have seen the diagrams on leaving 3 "posts" of holding wood, and then drop it. :jawdrop:

Line up cuts from both sides... I have had my problems with this.
First requirement is a chain and bar that will cut straight.
Second is keeping the off balance power head from influencing the cut.
Good luck. I used to use a 041 (awsum saw). MS460 now.

-pat

 

[smokechase II]

boring stuff

One way to break into boring technique is to start on wood types least likely to kickback when being plunge cut.
Rotten wood,
then softwood,
then hardwood,
then dead/dried, but not starting to rot, hardwood.

Consider developing a technique where your body, or most of it, is slightly off-set from the probably bar return on one of the three forms of kickback.

Both thumbs wrapped always.
Shorter bar better for learning on with decreased leverage.

 

[Crofter]

What chain is preferred for easy boring cuts. I have found Oregon LP to be less kick prone yet faster boring than LG (or the equivalent Carlton). Some chains almost refuse to penetrate with the nose after a few sharpenings unless you remove material well down over the bullet nose of the depth gauges ( rakers)

 

[sawn_penn]

Boring speed is the major problem with safety chains. Many safety chains cut fast enough, despite what people say. Safety chains don't bore well though, because they are designed to stop the tip from catching the wood. The bumpers stop the cutters from getting a good bite. (The bumpers also discourage the saw from being thrown at your head.)

So... if you really need to bore (because you drop heavy leaners, etc) get a chain that will bore fast and keep you safer (safer from splitting trees, etc)

If you mainly want to buck and limb, get a safety chain that will keep you safer (safer from kickback)

 

[smokechase II]

chain kick back stuff

As I understand it.
There are only two types of bars that are truly non-kick back with regard to the top of the tip kicking back.
1) A type with an extremely small tip used by wood carvers.
2) The bars with an end cover, (that is usually promptly removed, negating its anti-kick back feature.)

Chains can have a reduced kick back tendency if:
1) Full comp, lots of teeth.
2) A type of guide (raker) that has sort of an extension that goes forward about another link. This is to reduce, (in theory) the distance a tooth could sink into the wood on its own. While this is a good idea, for making a safer chain, when a chain is going around a corner, this limiter is limited in its effectiveness.
3) Somewhat higher rakers, say 25 thousandths. This is to reduce, (in theory) the distance a tooth could sink into the wood on its own.
4) Type of tooth, rounded teeth cut less efficiently, but will have a tendency not to dive into the wood.

Sort of a general rule here is the set up that will cut the best, is the least safe.
I like chisel chain, full skip, longer bar, rakers at 35 thousandths most of the time. But I'm somewhat experienced, older and reasonably careful, constantly am working on thumb stuff as I try to correct the errors of my youth and wear a $70+ Stihl chap.

Almost all of the experienced types reading this are thinking; "He better mention avoidance and chaps and thumb placement again and again."

 

[RES]

Can someone explain to me the philosophy behind boring heavy leaners? Also I didn't understand the stuff about the triangle. Do you still place a notch on the leaned side? I assume barber chairing means that the base of the tree is going to pop up. Sorry for my ignorance.

 

[musher]

The weight of the leaning tree is going to start to pull the tree down before you finish your back cut. The idea behind a plunge cut is make the face cut, then bore in and cut from the hinge back toward the back of the tree, and lastly, to cut the holding "strap" of wood at the back of the tree. That will keep the tree from coming down before the cut is finished, and the tree won't split vertically (creating a barber chair).

 

[DeanBrown3D]

If you look at a barber chair, its always the wood right behind the hinge that's toast. Bore this out but leave a section of holding wood right at the back of the tree, opposite the face. You can cut this section fast too. I try to picture it as this: imagine someone is holding a tree up in the air but horizontally, holding it by its base. How would you saw cut it into long sections? You'd make a face cut at the bottom, then bore in behind the face, and finally you'd cut the 'top' piece of holding wood, thereby minimizing splitting.