Fir Zip-line

[skyhuck]

When the section is committed to going over I sever the hinge, this eliminates the force of the timber pushing you backwards and giving you a ride. I like it and I'm sure it's not for everyone. Make sure it's committed before you sever the hinge!

 

Sorry, I thought we were discussing the cut in the video.

[Stephen Blair]

High scale explained it very well on 1 of Mikes threads Huck

ask him lol

[Paul Smith]

No worries! I am sure Reg wouldn't mind the high jack

[RC0]

The diagonal cut of a face generally extends further than the horizontal, which ever style face cut you use. When the face closes the diagonal cut nearly always overhangs past the horizontal until the hinge breaks and the tree is released from the stump, the wider the notch the greater degree of extension.... for this reason the Humboldt cut appears to break the hinge quicker (say the traditional face requires 30 degrees of movement before release and the Humboldt takes only 20). Make your notch relatively narrow so the tree is released at the point when its forward momentum is the greatest, which is more effective in throwing the tree clear of the stump....that top corner of the Humboldt (horizontal-cut) also appears to help with the throw as it deflects of the horizontal.

 

There must be sufficient top weight to make it work though....say on short logs it can stall as the face closes and just sit there. Then you’ve got to sever what remains often resulting in the log falling off sideways.

 

I thought the Humboldt was BS until I started experimenting with it a few years back, now I’m a believer.

 

Out here I’m obviously doing a lot more free-falling and topping-out tall trees....while back in the UK the technique had very little benefit to the type of work I was generally involved with. Thanks again.

 

1 What are the reasons for not felling with a tirfor on those 2 ocassions?

2 When knocking out lengths, do you measure them so to use them for production?

 

Hi Stevie

 

Setting a wet 200+ pull line at 130ft is work enough....adding a steel cable an the tensioning it to an unquatifiable ammount wouldn't really benefit the situation much.

 

I'm not sure which part of the second vid (taller tree) a tirfor might have been useful either.

 

The very high logs aren't all that critical, because they're generall more knotty....the lower stuff is obviouslly mesured if its a desireble species like Doug fir or WR Cedar. Cheers

[RC0]

that top corner of the Humboldt (horizontal-cut) also appears to help with the throw as it deflects of the horizontal.

 

 

Edit: that top corner of the Humboldt (horizontal-cut) also appears to help with the throw as it deflects of the diagonal.

[Stephen Blair]

Cheers Reg, I never took into account the length of wire rope required on trees that height lol.

 

I would just be trying to get out climbing that high tbh. Ha

 

 

great work as usual.

[skyhuck]

The diagonal cut of a face generally extends further than the horizontal, which ever style face cut you use. When the face closes the diagonal cut nearly always overhangs past the horizontal until the hinge breaks and the tree is released from the stump, the wider the notch the greater degree of extension.... for this reason the Humboldt cut appears to break the hinge quicker (say the traditional face requires 30 degrees of movement before release and the Humboldt takes only 20). Make your notch relatively narrow so the tree is released at the point when its forward momentum is the greatest, which is more effective in throwing the tree clear of the stump....that top corner of the Humboldt (horizontal-cut) also appears to help with the throw as it deflects of the horizontal.

 

There must be sufficient top weight to make it work though....say on short logs it can stall as the face closes and just sit there. Then you’ve got to sever what remains often resulting in the log falling off sideways.

 

I thought the Humboldt was BS until I started experimenting with it a few years back, now I’m a believer.

 

Out here I’m obviously doing a lot more free-falling and topping-out tall trees....while back in the UK the technique had very little benefit to the type of work I was generally involved with. Thanks again.

 

 

 

 

Interesting stuff Reg, thats the best explanation I have heard as too why it works

 

I'm still struggling to understand why it makes a difference though??

 

The two surfaces meet which ever way up the cut is, the energy will be the same in both cuts, I'm just trying to work out why which surface is on the moving piece makes a difference??

 

I will have to give it a try.

 

Thanks for taking the time

[High Scale]

High scale explained it very well on 1 of Mikes threads Huck

ask him lol

 

I did?

[morten]

I use the humbolt cut a lot and I prefer it. The top goes over more

and then I sever the hinge with no danger of a sit back and it pops off.

 

I, too, use the "upside down" humboldt cut. But I see no reason why it should behave any different to a "normal" gob during the felling.

 

In forestry, the Humboldt cut is used mostly to reduce the timber waste near the base.

 

In arborist work, I use the Humboldt for convenience. Especially when making the cut with the top of the bar, it gives me a more convenient position of the saw (not having to twist it as much).

[High Scale]

Mr Beranek describes the Humbolt in his book, The negative cut (the lower cut) greatly improves the tendency of the butt of the tree to slip off the stump during the trees fall, particulary when the tree is felled to the sidehill or downhill.