Thumb Turn In Commercial Glass Door Will Not Turn

Notice the photo on the left. This is a thumb turn made by U.S. Lock. Notice also that you can see holes on the top. Also imagine that dirt dobbers make nests in your hollow aluminum door and that, as the door is used, debris falls into the holes and jams the lock. Be sure to always ask for a thumb turn that has a cap on the cylinder holes. Sometimes, however, the thumb turn quits and dirt dobbers are not the problem. If your thumb turn is hard to turn, and you feel a grind, you can do these things. (Also note it is threaded and has a set screw channel.)

1. Look at the thumb turn on the inside of the door. Spray WD-40 around the actual thumb piece so the oil will penetrate into the thumb turn. Be sure to have a paper towel ready. (If you feel grit, read below, unscrew the turn all of the way out and flush it with WD-40.)
2. If the thumb turn still grinds, loosen the three screws holding on the lock plate on the edge of the door. Now, where you see the thumb turn, imagine it as if it were a clock. At 9 o'clock, or 6 o'clock, on the edge of the door where you see the lock body, you will see a small, countersunk set screw. Unloosen it two or three turns only. Make sure the thumb turn is in the open position. That means, when you turn the thumb turn, you will feel it grab slightly with a spring and ball bearing. This holds the turn in open position. The turn itself will be pointing to 6 and 12 o'clock. If you do not feel the bearing, then turn the thumb turn 180 degrees, or just reverse it. (The lock cannot be removed if it is not in open because a lock cam is trying to activate the lock and hangs down into the lock, barring any attempt to remove it.)
3. With the set screw loosened, grab the outer body of the thumb turn and turn it counter clockwise, unloosening it, one complete turn.  If you cannot move it, simply unloosen the two lock screws on the edge of the door that hold the bolt in. Tighten the set screw, tighten the lock screws, test the thumb turn. If this doesn't work, go to a better hardware store and buy a new turn. Locksmith's buy these for $6.00 and install them for $75 to $125.