Bore height

SasquatchMan · February 14, 2004, 07:36:28 AM

If a guy is gonna do a plunge and bore type cut on a big tree, what's the safest height to do it at? I've sort of ruled out neck-high, and I would think that a guy would have most control at about waist-level.
If things go wrong and you get a barber-chair out of it, is it safer to have the thing a bit lower?

beenthere · February 14, 2004, 08:47:37 AM

Why do a high stump, as it wastes the lumber recovery from the lower part of the bowl of the tree? If cutting for firewood, it doesn't matter.

Control of the saw is primary when plunge (bore) cutting, and not difficult. You shouldn't experience kickback, only the possibility is there, so just realize that holding the saw loose (no control) is when kickback comes back too far

Frickman · February 14, 2004, 05:27:01 PM

In our area with hardwood timber a large tree is usually a valuable tree, so you want to recover as much as possible. I notch the tree as close to the ground as possible, and make the backcut at the level of the hinge or about one inch above. If you make an open face notch, you will have better control of the tree than if you go higher with your backcut. If you are pulling the tree with a cable or chain you must cut below the hinge to prevent the hinge from breaking and the tree kicking off the stump.

Like beenthere stated, you must exercise extreme care when plunge cutting. Just bore in using the bottom quadrant of the nose of the bar and follow it in. If you use the top quadrant, you will likely experience kickback. Bore in, and saw toward the notch and "setup" your hinge. Then saw away from the hinge to release the tree. I always insert wedges into the sawcut, just in case the tree needs some help falling. If your bar does not reach across the stump, setup the hinge on one side, and cut the backcut on that side, not removing more than 50% of the wood. Go to the other side, setup the hinge, and saw back until you release the tree.

One thing you have to remember in the hardwoods I cut is make sure you have good wood for the hinge. Not only sound, but straight grain. On a tree with a large swelled butt the grain changes angles and starts to run more horizontal. I have found that this wood break easily, as the the grain does not run straight through the hinge. The end result is the hinge may break before the tree has fallen and thus the hinge is no longer controlling its fall. This can lead to the tree falling someplace you don't want it to. The lumber or veneer from this portion usually does not have much value, so you can make the notch a little higher.

I have used these techniques for years and have not "barber chaired" a tree in recent memory. There is no big secret in cutting most trees. Just take your time, develop a plan, and make accurate cuts.

SasquatchMan · February 14, 2004, 05:47:14 PM

Thanks... I've got the theory, and I'm not too worried about a kickback (and in fact, there aren't too many trees near me that would require this). I just haven't had a chance to practice the technique, and I wanted some advice. I'm not worried about lumber recovery, as I'm just cutting firewood on crown land.

Kevin · February 14, 2004, 05:49:03 PM

For fire wood it doesn't much matter but try and pick a clean place without knots or other deformaties.
This is how I usually bore cut with an open face notch ...

* make the back cut from outside and just slightly below the bore so the wood fractures.

Sawyerfortyish · February 15, 2004, 05:59:50 AM

SM I always cut low stumps 4 to 6" from the ground. As Frickman said and i'll say again on veneer logs that high stump may have 20 or 30bf of lumber at over a buck a foot left to waste it don't take long to leave a lot of money in stumps! If your cutting firewood and leaving high stumps consider getting it out. If you use a pickup you will always be driving or backing into them if you use a tractor or skidder you will always be bouncing over or hooking the bottom on them so cut them low.

Ron Scott · February 15, 2004, 09:51:39 AM

Or damage other veneer quality trees should the falling tree hit a high stump. High stumps are also unsightly and a sign of unprofessional logging.

We allow no sawlog stumps to be higher than 12" and 8" for pulpwood sized trees. High stumps are usually not a problem since the loggers know where their wood value is as stated above.

IndyIan · February 16, 2004, 10:39:08 AM

SasquatchMan,
For practice doing plunge cuts, try them on cedar or white pine. The softer wood doesn't make the saw kickback as hard as hardwoods when you are learning. I guess a low kickback chain would help as well.

Right now I'm cutting white cedar and some are in clumps so using the plunge cut lets me cut trees without touching one right beside it. Also I'm using a 16" bar so most of the time I'm using plunge cuts for felling. Usually I get my leg or hip behind my right hand on the saw so if the saw wants to come back at me it has to move my whole body.

Have fun,
Ian

SasquatchMan · February 18, 2004, 07:05:41 PM

Purely firewood...

The chance of me actually having to do that in central-western alberta is pretty small. I went out the other day and got a coupla truckloads and the biggest tree was about 16" at the base. I just sorta wanna know how to do it if the time comes...

I was basically using the open face method outlined on Jonsered's Canadian website, and was dropping 50 footers within 5 feet of where I wanted em. Only smushed one poor little tree.

Kevin, what's the advantage in cutting below your bore? I don't quite understand what that helps/achieves.

Thanks lads.

Kevin · February 18, 2004, 08:19:23 PM

If you cut a little too high you may end up with a saw grabber.
I prefer the way it releases, a little slower adding a little more control.
I picked the idea up from a pro logger but I can't remember who it was.

SasquatchMan · February 18, 2004, 08:29:37 PM

So the trick is to leave enough meat that you can extract saw and self, then give the tree a wee push and the extra goes snap and over she goes... Makes sense - that's a cool addition to the usual bore/strap. I'll go try it on a big 12 incher!! :D :D

Ianab · February 18, 2004, 09:09:29 PM

I've had to practise my bore cuts lately
Here are a couple of pics of a pretty hairy one.....
Stump is about 36" and was cut with a 20" bar, with the cuts actually lining up in the middle for a change :D
This tree had everything stacked against it >:(
It was growing on a 20 deg lean, all the branches were on the same side as the lean, it's on the side of a 45 deg hillside and it's macrocarpa cypress that has a reputaion for barberchairs.
Because of the stress on the tree the back strap tore out as I was cutting it, this will have stuffed the first 18" of the log. Cutting the holding strap lower might have helped in hindsight (any other hints or tricks) ??? Even though I was expecting this to snap it sure went with a bang that made me jump back.
Then because it only fell about 30 degs onto the hillside, the branches didn't break much, and we were left with a log sitting 12 ft up in the air still >:( Thats a whole other story, but it's now on the ground and ready to mill, if this dang rain ever stops!

Tom · February 19, 2004, 06:13:12 AM

I'll bet you're glad that the stump caught the trunk. It looks like that tree would have been at the bottom of the hill if the notch had gotten on top of the stump.

I'm sure glad we don't have to deal with hills like that around here too much. Having flat land is kinda nice sometimes.

IndyIan · February 19, 2004, 06:51:01 AM

Ianab,
That looks like a tricky tree. I'd be afraid of it chasing me down the hill but the thick hinge you left worked well to keep it on the stump.
So you used Kevin's method for bore cutting and still got tear out? The only thing I can think of that would help is to leave your back strap wider and thinner so when you cut it you get through most of it immediately. Also if you do get tear out its going to be at the edge of the tree and probably will come off in a slab anyways.
Good pictures too!
Ian

SasquatchMan · February 19, 2004, 07:11:07 AM

:D :D :D Wow. Makes me glad to be a prairie boy.

Larry · February 20, 2004, 10:57:05 AM

I've had several people ask me how I bore cut so I put together a little photo sequence on my web site so people could get a better idea of what it is about.

Cutting A Tree My Way

SasquatchMan · February 21, 2004, 09:50:06 AM

Looks good larry. Now this may seem like a dummy sort of question, but my understanding of a bore cut is that a guy hollows out the tree from the notch side, leaving a horseshoe shaped area of tree, which is then cut out leaving hinge and strap.

It looks like you did what I know as "sectioning" on your tree. Or have I got it backward?

Larry · February 21, 2004, 02:50:10 PM

I guess yes and no. I bore in from the notch on high dollar walnuts with a horseshoe shape and leave two very small hinges on each side just like a door. I don't want any chance of splinter pull or splitting. Sometimes I bore in from the notch on a tree that is over twice the length of the bar when I'm too lazy to get the 066 or put on a bigger bar. 90% of the time I just bore in a couple of inches behind the hinge and creep up on it to get the right thickness hinge and than cut to the back of the tree.

Kevin has a really good link with all the proper procedures. I didn't bookmark it but maybe he will wander by and post the link again. It is well worth reading.

SasquatchMan · February 21, 2004, 04:59:28 PM

What I really like about these techniques is that you have all sorts of time to set up a perfect hinge, both on the notch and the felling cut. I'm not that experienced yet, so being able to adjust things BEFORE the tree start falling seems like a hell of a good idea to me.

Frickman · February 21, 2004, 05:21:12 PM

That's a great thing about the bore method, you have all day to setup your hinge. As long as you have plenty of holding wood on the backside, you can stop at any time and take a break, tighten your chain, etc. without the tree going anywhere. Only when you have a small amount of wood left at the rear of the tree during your backcut do you need be concerned with how fast you are cutting.

The only time I usually pull the saw out and finish the backcut from the back is on a heavily leaning tree. The reason is that the bark will tear easier than the sapwood, causing the tree to fall too soon and create fiber pull in the outside sapwood. Also, the fibers may pull out of the stump, clear down to the roots several feet in the ground, sending them flying past your nose as you are standing there. As stated above, I will drop down several inches and cut in, allowing the holding wood to shear with the grain. When the tree is down you simply trim off this holding wood flush with the butt.

Ianab · February 22, 2004, 03:43:37 AM

Some good info on this post, and the bore cutting methods are by way the best for any 'difficult' tree. Being able to set up the hinge before making the felling cut and reducing the chance of barberchair can save you from a power of grief.
Thats a good set of pics on your page there Larry, thanks

Ian

Ianab · March 06, 2004, 10:27:28 PM

One more thing to watch with this method.
Keep the hinge thicker than you usually would. We had a problem with a tree yesterday (it was a heavy leaner again) where the hinge wood actually compressed under the weight and pinched the bar in the cut >:(
It wasn't a major disaster, we unbolted the powerhead (just so it couldn't get squashed by the falling tree) and cut the holding wood with another saw. Tree fell as expected and the bar and chain were left sitting on the stump.