Stand inside your garage with the door closed and look at the hinges between the sections. Somewhere on the flat of each one there is a stamped number. Usually a 1, 2, 3, or 4. Most people have never noticed them. A fair number of people who work on garage doors treat them as a part code.
They are not a part code. They are a position, and getting one wrong is a door that binds for the rest of its life while everybody blames the opener.
Why a hinge needs a number at all
Here is the thing a sectional door has to do, and it is more awkward than it looks.
When the door is closed, all the sections are in one flat vertical plane. When it is open, they are all in one flat horizontal plane. In between, they have to go around a curve — and while they are on that curve, adjacent sections are at an angle to each other.
Now think about where the rollers are. The roller lives on the hinge, and the hinge is at the joint between two sections. As the door goes round the curve, the two sections either side of that joint are pivoting away from each other, so the roller has to sit slightly further out from the door face than the sections do, or the top edge of the lower section will jam into the track.
How far out is not the same for every joint. It depends on how far up the door that joint is, because the curve is tighter at the top. So the hinges are made in graduated offsets.
- A number 1 hinge has the least offset and belongs in the lowest joint, between the bottom section and the one above it.
- Number 2 goes in the next joint up, and so on.
- On a four-section door you have 1, 2 and 3, with the bottom brackets and top fixtures handling the two ends.
The number is the row. That is the whole system, and it is rather good.
What happens when one is in the wrong row
Nothing dramatic. That is exactly the problem. A door with a hinge one number out will still open and close. It just does it while fighting itself.
A hinge with too little offset for its row holds the roller too close to the door, so the section corner is pressed toward the track through the curve. You get a scuff mark on the track, a distinctive rub at one point in the travel, and a roller that wears out noticeably faster than its nine siblings.
Too much offset and the roller is held away from where the track wants it, which loosens the door in the track and lets the whole section wander. On a windy day it rattles.
Either way the opener has to pull harder through that part of the travel. If it is a modern opener with force sensing, it may start reversing near the top for no reason anyone can find. That symptom sends a lot of people out to buy an opener.
How this happens in the first place
Almost always a previous repair. A hinge cracks, somebody replaces it with whatever was in the van, and a 2 goes in where a 3 was. It is a small part and it looks interchangeable.
The other way is a section swap. A replacement panel arrives, the hinges come off the old one and go back on in whatever order they came off in, and now two rows are wrong.
The third way, and the one worth knowing about if you have an older door, is fatigue. The steel around the pivot hole wears oval after enough cycles. An ovalled hinge is effectively a different offset that changes under load, which produces a door that is fine some days and not others.
How to check yours
Close the door. Stand inside. Read the numbers along each horizontal row of hinges.
Every hinge in the same row should carry the same number, and the numbers should increase as you go up the door. That is it. It takes about ninety seconds and it is the single most satisfying inspection available to a homeowner, because for once there is a right answer printed on the part.
While you are there, look at the pivot points. A hinge that has worn into an oval is visible: the pin will sit off-centre and there will be a bright ring of worn metal around it.
The money question
Hinges are among the least expensive parts on the door, and a set is a short visit.
What decides the number is what the wrong hinge has been doing while it was wrong. If it has been rubbing a track for two years, the track has a worn stripe in it and possibly a burr. If the roller in that position has been taking a side load, it is finished. If the section corner has been pressed against the track long enough, the end stile may be deformed and that is section work.
So the honest answer is that hinges cost very little and the second year of a wrong hinge costs considerably more than the first.
What not to buy
- Do not buy a matched set of all-one-number hinges. They are sold. They are for a specific job, which is not your door.
- Do not buy an opener because the door binds near the top. Check the hinges and the top fixture first. It is a ninety-second check against the most expensive purchase on the door.
- Do not buy galvanised hardware and expect it to solve wear. Coating resists corrosion. It does not resist a hole being worn oval by a million cycles.
- Do not accept a hinge replacement that does not mention the number. If the person handing you the invoice cannot tell you which row it went in, it went in somewhere.
The short version
Your garage door is stamped with instructions. They have been in there the whole time, facing into the garage, waiting for somebody to read them.
We would love to tell you this is specialist knowledge. It is a number on a bracket, four feet from where you park, and now you know what it means. Feel free not to call us about it.
J&A Garage Door Repair · (707) 200-7682 · jagaragedoorrepair.com
Lic. 1133099 · Serving Sacramento and the Central Valley.