Garage door "stiffner" broken
Here is one I never have heard of, nor seen i a forum.
My 30 year old plywood sectional garage door (16x7) has U shaped "stiffeners" running the length of each panel, to keep the 16' plywood door from sagging or bending during operation. Up to now, these have been trouble free, but recently, the top stiffener on the top panel cracked in two right in the center. This caused my Genie screw drive opener to strain, and bend the track down as it got about 20% open, and thus hang the opener.
I was able to effect a temporary repair by placing a 3' piece of angle iron I had on hand in the vicinity of the cracked stiffener, using some carriage bolts. It still sags a bit when opening, but not enough to hang the opener.
After much thought and careful examination, I have come to the conclusion the cause and effect: the torsion springs have gotten weak, and the opener was struggling to open the door, which caused the door to flex inward as it was being dragged open by the opener, eventually snapping the stiffener. This then created a situation where the door was flexing as it transitioned from being pulled up to being pulled back, and the flexing translated to the opener carriage, and then the opener rail, and eventually caused a bind at one of the 3 joints in the rail, jamming the operation.
Moral of the story, check the tension on the springs a bit more often, to make sure the door is properly counter balanced, otherwise, you could end up with a host of problems like me.