This is a close-up of the trigger and the newly finished trough. The trigger is a piece of steel cable that is put over the beam to hold it down. On the end of that cable is a ring. This ring goes in between 2 other rings on the frame. When a rod or in this case, a large screw eye with the threads cut off, voila! you have a very simple trigger! The trough is made out of the rest of that 3/4" plywood with 1" by 2" side things.
