Hi Rodger AS, late but I am getting there. I have not done one exactly like this but the system is too simple not to work. The track system should also stiffen up the tree as well. You can also use guys on the track if needed. The three guy system can be carried up to the proper place below the blades by the carriage and the cable to the wench will be the third guy wire if you locate the wench on the lower part of a tree trunk behind the tree with the track. These drawings are ruff but I think I have drawn out most of the important points to make it work for you...
After you have prepped the tree and assembled the track on the ground, the winch will take the top of the unit to an upright position so you can mount it to the tree, about 200 lbs. And a boat wench is usually about 2000 lb capacity. Use a rope like I have drawn to keep from crimping the cable as it doubles back on itself. You can use a longer pipe to extend the mill even higher above the carriage if desired or make the whole thing longer. If you use the 4x4 lumber to make the carriage be sure to rip it down to the same slope as the tree to keep the mill level on the tower top pivot. I used a plastic butter cup as a shroud to keep some of the weather out of my idler pulley bearings.
Lowes has the track for about a buck a foot, I did not check the price of the rollers but they carry them if you have a store in your area. Use pl 400 or liquid nails between all surfaces and especially around the track and lots of screws. Also make sure the rollers work inside the track without hitting bolt or screw heads. If I can help further let me know. pepa
