Is this pocket door hardware missing a piece to lock the nut?

Question

I have a pocket door that was installed about a year ago and that frequently sticks. The contractor who installed it has made about three repair attempts. He will do something to it (I haven't been able to be there when he fixes it). It will then work for a while, then a few weeks later it starts sticking again. The sticking seems to come from it not hanging level causing the base of the door to catch on the threshold.

Looking at the door it hangs on two rollers, and the height on each hanger can be adjusted by turning a bolt. I think what the contractor is doing is adjusting the bolts on the rollers. There is nothing stopping these bolts from turning once they are adjusted - I can turn the one in the photo with my finger if there is no tension on it (there is no tension because the door sticks on the other corner). This seems wrong - the videos I've seen of people fixing pocket doors include a locking tab of some kind that you put in place after adjusting the bolt so that it can't work its way loose again. You can also see a locking tab in this other stackoverflow pocket door question.

I'm suspicious that a piece of the hardware was left out during installation and this is why the fixes the contractor makes don't last long.

My main question:

1. Is there a piece of hardware missing here?

Bonus questions:

2. Can anyone identify what part number this is so I can find the installation instructions?

3. If it's not meant to have any additional locking tab, what is supposed to stop the nut from working loose - should it have threadlock on it?

Answer 1

There should be a nut on the threads of the adjusting rod to lock it in place.

It can be complicated now to get one installed, but that should be your contractors responsibility.

Call them back and offer it as a suggestion so they do not have to be returning to your place every few weeks.

Answer 2

I've installed many pocket doors and owned a few. I don't recall ever having to tighten a lock nut. It's awkward enough getting the little bent wrench in there to adjust the thing in the first place.

As I recall there are detents built into the adjuster. They may be at the bottom of the bolt where it engages the door mounting plate. When you rotate the nut, it should feel like it's clicking into notches. The weight of the door itself locks position in these detents.

Either that or there's a nylon insert providing friction. In any case, I recall some of them being rather stiff to turn.

Therefore, I doubt that a loosening adjuster is the cause of your problem. Firstly, there should be enough of a gap under the door to accommodate seasonal movement, etc. If there isn't say 3/8" to 1/2", and you're out of adjustment range, I would shorten the slab. A power planer or circular saw would do that job, followed by a small chamfer with a sander. Tape the surface first to prevent splintering.

Then, if things are moving that much, look for sag in the head frame. It's usually suspended from the rough opening by sheet metal straps, but maybe they weren't attached properly. You could firm it up with long screws judiciously applied.

By the way, you can probably find the manufacturer info by dropping one of the trolleys out of the track. Most hardware has a mechanism to allow removal of the door (detachment of the trolley from the door bracket). In your case there may be a rotating catch on the door mounting plate which locks a ball or tab in place. Once you detach the trolley and rest the door on the floor you can roll the trolley to the end of the track and tilt it out the gap between the end of the track and the jamb.