The barn is two years old and all of a sudden both overhead garage doors are jamming.  What could it be?

We had a beautiful 40X15 food barn built and delivered by Wood Tex.  All was well until the end of last year when suddenly both doors began binding when raising or lowering them.  We first speculated that somehow one corner of the barn was sinking altho, with 10 inches of crushed stone as a foundation that seemed unlikely.  So I got my laser level out and shot both ends of the barn to see if our suspicions were true.  Nope, just as level as the day it was carefully placed there so precisely by the Wood Tex technician!

I continued my investigation and found a plastic covered card wired to the frame on top of the door rail.  It described how to adjust the spring tension in the lift-assist mechanism on top of the door frame.  I started investigating and found that one of the cables was a lot looser than the other!  One plucked like a guitar string and the other was loose as a goose.  I read all about the adjustment procedure for the spring and determined that it called for adjusting both sides equally so it appeared that I could not compensate for the loose cable by the adjustment procedure.  Then I found it!  There is a tapered drum on each side of the door, attached to the spring loaded shaft.  The cable which is attached to the bottom of the door is wrapped around this tapered drum.  However on the slack cable side I noticed that the cable was not wrapping correctly, it was wrapping on the small end of the tapered drum.  (see picture below)

The cable was tight since the door was all the way down so I relieved the spring tension on it by using a vice-grip clamped to the spring shaft and was able to overcome the spring force, loosen the cable and slide it back into position on the large diameter groove.  (see below)

Now that both cables were on the same diameter of the take-up spool the tension in them was equal and the door lifted with one finger, no longer rubbing along the edge of the frame.