Wound to the door, balanced by hand

How we spec and wind a torsion spring

A torsion spring is sized to the door it lifts. So the first thing we do is figure out what that door weighs and how far it travels. Wire size, inside diameter, length and wind direction all have to match. Miss on any one of those and the door either sits heavy on the floor or floats off the seal at the bottom. We pull the arm off the opener and lift the door by hand to see where it wants to sit, before we order a thing.

The old spring comes off with the door clamped in the track and the opener unplugged, because a door that gets away from you on the way down wrecks whatever is under it. New spring on the shaft. Cones set. Then we wind it with bars, a quarter turn at a time, counting out loud as we go. The last of the tension gets set by feel, then checked against the door itself: lift it to about waist height, let go, and it should sit there without creeping.

On a door with a pair of springs we change both, even when only one let go. They were wound the same day and they've taken the same cycles, so the second one isn't far behind, and a mismatched pair pulls the shaft unevenly and starts chewing up bearings. Balance is the part that gets skipped. A door left heavy runs fine for a while on a strong opener. Then the gear inside that opener strips out, and what was a spring call turns into an opener call.

• Door weighed and the spring sized to it
• Both springs changed on a two spring door
• Cables inspected end to end, drums reseated
• Door balanced by hand at half open
• Opener force and safety reverse checked after

Cables, drums, and a door that hangs crooked

The cables do the lifting. Each one runs from a bracket at the bottom corner of the door up to a grooved drum on the spring shaft, and the drum winds it on in a tight spiral as the door goes up. Slack is what kills them. A door that lands on a bag of mulch, or a spring that snaps with the door halfway up, lets the cable jump out of the groove. After that it either wads up against the end bearing or comes off the drum for good.

Putting one back on takes more than threading it into the groove. Both drums have to sit against the bearings with the same tension, the set screws have to bite on the flat of the shaft, and the door has to be level in the opening before anything gets snugged down. Get that wrong and the door climbs one side. The top section racks in the opening, rollers start dragging on one track, and you'll hear it from inside the house before you ever see it.

A cable that's been rubbing gives itself away. The strands fuzz up where it wraps the drum, or where it turns at the bottom bracket, and once a few have popped the rest are carrying everything. We change cables in pairs for the same reason we do springs. And the bottom brackets they hook into are the piece folks get hurt on, because that bracket holds the door's weight through the cable even while the door is sitting flat on the slab.

What our weather does to spring steel

Summers here are wet and the air sits heavy in a garage with no heat in it. Steel that's a few degrees cooler than the air pulls moisture right out of it, so a spring can be damp most mornings from June through September and nobody notices. Rust works slower than that. It roughens the coils so they grind on each other instead of sliding, and every cycle after that takes a little more out of the steel than it should.

Winter is short around here. Doesn't matter. A door that freezes to the slab after a wet cold night is stuck to that concrete, and the opener will happily try to lift it anyway. That's where cables let go, usually one side first, and the door ends up hanging by one corner with the other cable in a bird's nest around the shaft. If the door won't move in the cold, take your thumb off the button. Break the seal loose at the bottom first.

The bottom of a cable rusts long before the top does. Water runs off a car, or blows in under the door in a hard rain, and it sits on the slab right where the cable meets the bracket. On a detached shop, or a garage off a gravel drive, it's worse, because grit gets in that same corner and works like sandpaper. So when we're in there for a spring we run a hand down both cables, drum to bracket. That's the stretch you can't see from the driveway.

The hardware a spring hangs on

A torsion spring is only as good as what it's bolted to. The center bracket carries the whole load, and it's lagged into the header over the opening, which on a lot of the older brick ranches out here is a piece of framing lumber that has spent decades in a damp garage. If those lags spin when you back them out, the wood has gone soft and the bracket has been creeping. New spring, same tired header, and you're right back to a door that won't stay square.

End bearing plates take the other half of it, one at each side, and they're why a lot of doors get loud. A dry bearing squeals. Then it wallows out, the shaft starts riding low, and the cable quits feeding onto the drum straight. Swapping a spring without turning that shaft by hand to feel the bearings is doing half a job. Takes a couple of minutes to check, and it's the difference between a quiet door and one you can hear from the back bedroom.

Plenty of the older doors still run extension springs, the long ones stretched along the horizontal track on each side. Those need a safety cable threaded through the middle of the spring and anchored at both ends, and a lot of them out this way never had one. When an extension spring lets go without that cable, it comes across the garage. If we open a door and find a bare one hanging over your car, we'll say so before we touch anything else.

Doors around Stanfield and what they take

A single bay on the side of a brick ranch is a light door, and it usually runs one spring on a short shaft. The double doors on the newer builds through Midland, Unionville and Indian Trail are a different animal. Wider, heavier, and carried by a pair of springs that have to match each other. Same job, twice the consequence when the balance is off, because a heavy double coming down out of control usually has a car sitting under it.

Out past Albemarle the doors get bigger and the use gets harder. A shop door that goes up and down a dozen times before lunch eats a spring on a schedule you could almost mark on a calendar, so it's worth putting a higher cycle spring on that one the first time around. Farm buildings tell the same story with more dust in the bearings. We'd rather spec a door for the work it actually does than for whatever the original builder hung on it.

We work out of Barbee Road, so most of these calls are a short run from the shop: Stanfield, Midland, Fairview, Concord, Monroe, Matthews. The listing sits at 4.9 from 37 Google reviews, and what people write about most is reasonable pricing and the workmanship, which is what you want on a job nobody looks at again once the door is closed. Shop hours are Monday to Friday, 8:00 AM to 5:00 PM. The number is (704) 960-0190.