Question... If I am trying to fall a leaning tree in the opposite direction of the lean, If I get a rope up in it and can pull on the rope hard enough that I see the canopy move in the direction that I want it to fall, is that a 100% indication that I can pull it on over once I have made my face cut and back cut? Assuming I am high enough to get good leverage and pulling on the trunk, and not up so high that I am pulling on just the canopy branches. Would that hold true for any size tree with any amount of lean? If I pull too hard it could barberchair, correct?
I am a hack so if one of the pro's have a better idea then just listen to them. But here is what works for me when I want to pull a tree against it's natural lean. I am also open to constructive criticism if I am doing something wrong.
First have a chain, rope, or (least preferably) cable that has a breaking strength several times the weight of what you are attempting to pull over.
1) Get up as high as you can to fasten the line to the tree while not getting so high that you run the risk of breaking the trunk if you pull on it to hard.
2) Once you have the line secured put a little bit of tension on it.
3) Then put in your face.
4) Then tighten up again, if the tree will let you.
5) Now you are ready for the back cut. I find this is best executed with someone else on hand so they can do the tightening (either cranking on the chain hoist or driving the vehicle) while you watch the tree. If I am pulling with a truck I will advise the driver to put it in gear and if tree allows it to start rolling forward just go with it. As you start the back cut you can judge if it is opening up or not. Have the "puller" put a little more tension on the line if it isn't moving after you have put in a good back cut. DO NOT over stress things or something is prone to break (the line, the trunk, the hinge, or the pulling vehicle/anchor) and things will go to heck quickly. If you have done things right usually the tree will get over it's center of gravity around the time you get done with the face cut and come down where you want it.
WARNING and I learned this the hard way, luckily without damage. If the tree is tipped too far back or has a decent amount of side lean you will want to find a different way to drop it. Otherwise you run the risk of having the hinge explode and the tree tipping 90 degrees to where you want it to go.
Of course no two trees are the same. I know with the aspens I frequently deal with there is a high risk of advanced core rot higher up in the tree and they could blow up at any time.
Hope this makes sense and if I have any fatal flaws in my procedures I am open to suggestions.