Depending on the size and weight of the plate you may be able to get away with one gin pole.
We built one here and then built a windlass to wind up the rope.
Works great, here is a shot of just the gin pole with two 8x8x16' timbers weighing 500 lbs total:
Here is a shot of the windlass (wooden winch):
Here is a helper tailing the line:
With this setup, I was able to pick up these two timbers totaling 500 lbs with one hand on the handle of the windlass and one hand on the camera to take a picture:
The load was 500 lbs, the blocks had four pulleys in them so the mechanical advantage was 4 to 1 so 500 / 4 = 125 lbs going to the windlass. The windlass mechanical advantage is based on the diameter of the drum vs the diameter of the circle at end of the handles (if I understand it correctly). Which is 13.5 to 1. So 125 lbs / 13.5 = 9.25 lbs. There are four handle ends so 9.25 lbs / 4 = 2.31 lbs if four people were turning the windlass. So alone, I only had to push one handle about 10 lbs pressure to lift 500 lbs of timbers.
Works for me.....
These are small enough to be transported around to different sites for raising frames.....
Jim Rogers
Have gin pole and windlass and will travel.....
