Garage door repairs can be very expensive to install and they can be very expensive to repair if something goes wrong with them, where ever possible it is far more desirable to repair a garage door yourself and following a few helpful repair tips will get you headed in the right direction.
In general terms a garage door can be divided into two main components, the actual garage door and the means to open the door. So called overhead garage doors generally come in two basic models, garage doors will either roll up in sections or will open in one solid piece. These types of garage door require spring tension to work properly, most garage doors use a spring or spring tension and a metal track to provide the garage door with the ability to open and close under a form of power.
The first step in finding out why your garage door is not working is to check the metal tracks that the garage door runs on. Check for any dents or dings as well as crimps in the rail that are either preventing the door from moving or causing it to get stuck. Use a rubber mallet to knock or flatten dongs and dents but if the rails are too damaged it will be better to replace them.
Next check the alignment of the rails, if the rails are not aligned perfectly then the garage door will not open and close properly. Use a level to check them for alignment. This is true for doors that open horizontally as well as doors that roll up, with roll up doors the rails need to be exactly plumb. If you find that they are not aligned then loosen the retaining bolts and adjust them until they are level or aligned, re tighten bolts.
Sometimes repair work to a garage gate can be as simple as a thorough cleaning with strong detergent, cleaning any built up grease and hardened dirt. Tighten any loose hardware that you find, often over time retaining bolts will loosen, go around the entire structure making sure that all bolts are tightened, on swing up doors the bolts that hold spring plates in place are usually the ones that get lose most often. With roll up doors there are often problems with hinges that hold sections together, makes sure that these are all tight and aligned correctly. Repair any cracks around the hinge by removing the hinge and filling the cracks with wood filler and letting it dry, it may be a good idea to put the hinge back in another section of the panel.