Are there any sizing parameters for the gin pole depending on length and wood species?
Well, we just used what we had on hand, which was eastern white pine. But to be technical you should figure out what your heaviest load would be and make sure a column or post of the size and type that you want to use will hold up that load. Probably strength parallel to grain psi value from the NDS or something like that.
What type of line did you use for the guys (I think that is the right term?) Those are anchored to your machine right?
In the failure test, which is the pictures I posted, yes the guy lines are attached to the backhoe fork attachment hooks, as well as the back line. These small white pieces of rope are actually one long piece that I made a loop in at the middle point so that I didn't have to cut it and it would be as long as possible. This was so that I could tie them off to other solid objects depending on the actual location where the gin pole was going to be used.
This/these lines are 3/8" braided nylon.
And lastly, Does the ginpole have to be set perpendicular to the pieces placement?
No, I don't think so, but it does help it to remain stable as the upside down "T" base prevents it from shifting/leaning side to side.
....and does it also have to have the block and tackle directly plumb over its placement too?
We did this so that when you lower the piece you don't have to swing it out or in to line it up over it's intended location.
The angle of the gin pole is not suppose to move right?
When I discussed this with Jack Sobon and the methods he used to raise his own side entry English barn, I asked him how he did it alone.
He told me that he put a peg in his gin pole so that when his timber was raised up as high as it needed to go he could tie off his lift line and it wouldn't allow the timber to come back down.
He also had a "safety line" that when from the top of the gin pole opposite the back line, tied off to something solid on the other side of his yard. This was to prevent the gin pole from going over backwards if the load shifted when fully raised. This seemed like a great idea to me as you are raising the center of gravity of the whole rig when a timber is up there.
He aligned his gin pole to be outside of his building and the lift block was not over the wall posts. After he raised his plate to the top he adjusted his back line and side guy lines to allow the gin pole, and plate to lean in over the post's top tenons. Then with a tag line on one end of the plate, to help guide it, he lowered the plate until the lower end was sitting on the tenon. He then re-tied the line off to the peg in the gin pole and went up his ladder to adjust the plate's alignment to the first post top tenon. Once this tenon was engaged into it's mortise he lowered the plate some more.
We usually have the lift point of the plate just off center a fraction so that one end will hang a little lower then the other end so that we can start with this low end to insert it's mortise onto the corner post's top tenon. Then that post's brace, then the next post down the wall and end with the last post or other end of the plate engaging the other corner post. This way you're not trying to align all post tenons and all brace tenons at once. Now this isn't much but just enough so that you can do this safely and easily.
By the way good questions.
Jim Rogers
