The older house we’ve just bought has a nice wood panel door leading from the hall into the garage. Unfortunately, the mortise-tenon joint nearest the lockset has opened a gap of about 1/8 inch between the rail and the style. (I hope I have the terminology correct!) In addition to looking bad, this makes the door hard to close.
I have considered:
1) Trying to inject glue into the joint and clamping it back into alignment.
2) Taking the door apart and regluing.
Rob Johnstone: Take the door off its hinges and put some clamps on it at the point of the gap. Test to see if you can snug the joint back up before you put any glue in the joint. If you can tighten things up with your clamp, open the joint back up, work some glue into the opening and clamp that baby tight. Allow the glue to cure for 24 hours and then rehang it. This will likely take care of things, but if there is some structural problem you can’t see, the problem may reoccur.
Michael Dresdner: Those are two very different options. The first one would be much easier, but the second one will actually work. The odds of such a joint holding after glue was injected into the gap are dismally low. However, if you take the door apart, you can clean the joint, refit it if necessary, and glue it up properly, after which it will hold.
Look for moving, bowing, or twisting wood on the stile when you take it apart, as this is the most probable cause for the gap in the first place. Machine the mating surfaces if you must, but make sure the joint goes together with no more than gentle pressure. If you have to force the parts to mate with clamps, it will eventually come apart again.