I have frequently noticed that a remedy is wanted for binding sliding doors. This question is very frequently asked, and it is not to be wondered at, for not one sliding door in ten put up works in anything like a satisfactory manner. I have had a great deal of experience with sliding doors, and am pretty well acquainted with the common defects and causes of unsatisfactory working. I do not wonder that a good remedy is wanted for these troublesome doors, for unless they work properly they become a great inconvenience. The causes of the unsatisfactory working of sliding doors are many, and a little general information on the subject may not come amiss. Nearly all the causes of the imperfect working of sliding doors can be traced directly to the improper construction of some part of the work in putting them up, and in most cases an ounce of prevention is worth about 4 pounds of the cure. As overhead hangers are almost exclusively used these are the ones we will take into consideration. First, it is necessary that the floor under sliding-door partitions should be perfectly solid and very nearly level.
It is a common occurrence for buildings to settle, and if partitions, which often have a great weight to support, are not provided with a properly constructed foundation, they will settle enough to throw the ordinary sliding door entirely out of working order. It will not do to block up under sliding-door partitions with a little chip, a piece of a shingle, a little loose dirt under a post in the cellar bottom or some fresh mortar, as is often practiced. As the increased weight of the plastering and floors is put upon the partitions above, the floors begin to settle. I have seen floors under sliding doors ½ inch out of level. How can sliding doors work when put up under such circumstances ? If the track was level, one door would be sure to strike the floor as it was rolled back, while the other door would rise almost 1½, inches from the floor. Again, if the track was not level, but placed parallel with the floor, then the doors could not be adjusted to hang plumb; consequently, they would not fit the jambs, unless the jambs were set to fit the doors ½ inch out of plumb.
Fig. 56. - Section showing Construction of Track and Boxing for Sliding Doors.
Thus far we see that the floor must be perfectly solid and level, the partitions must be set plumb, the headers put in solid and of sufficient strength to carry all the weight placed upon them without yielding or sagging. We will now turn our attention to the putting up of the track. This should be level and straight, and it should be straight sideways as well as on top where the rollers run. This is a point overlooked by many. They think if the track is straight on top that is all that is necessary, but short kinks sideways in a track will cause the doors to run crooked - running away from the stops on one side of the jamb, and crowding them on the other, often causing binding. Again, most hangers require a double track, constructed in the following manner: The track is 1 x 1½ inches, and screwed to the edge of a board ⅞ x 6 inches. These boards are then fastened to the partitions at the proper hight for the doors, and another piece 4½ inches wide, called a spreader, is placed over the top. The sketch, Fig. 56, gives a general idea of the construction of the track and boxing. In the diagram it will be noticed that the opening between the tracks and between the jambs, through which the lower part of the door hanger passes, is only one inch wide. The hangers have small friction rollers, which run between the two tracks, serving as a guide for the wheels above, and not leaving more than ⅛ inch play between the two tracks. This ⅛ inch is plenty of room if the work is properly done. It is necessary that the friction rollers run close to the track in order that the doors may run true and without crowding the door stops. But suppose the boxing is insecurely fastened to the studding, and the dampness from the plastering, when it is put on, causes the two 6-inch boards to cup. The tendency at once is to narrow the opening required by the friction rollers of the hangers, thus causing a binding of the door hangers between the two tracks. Again, suppose the spreader, which is for the sole purpose of keeping the tracks the right distance apart, is carelessly put in a little narrow, or, perhaps, left out entirely, as it is occasionally by some, who consider it an unnecessary appendage to the working of sliding doors, then there is practically nothing to keep the tracks from springing together, causing a binding of the doors.
Again, if the spreader is narrow or left out, the continual pounding of the lathers on the partition walls, and the carpenters in finishing, have a tendency to drive the partitions a little closer together, especially if they are not securely fastened at the top. Fully as many binding sliding doors are caused by the tracks springing together as in any other way, and when from this cause, the remedy is a difficult one to apply, as the doors may have to be taken down and the sides of the track trimmed off with very long-handled, sharp-edged tools. This cause of binding is likely to be overlooked, as it is the least suspected, and comes very near being an invisible cause. Again, we will suppose that a building being erected is to have sliding doors - that the tracks are put in level and at the proper time. Now, after the building has been plastered and the carpenter comes to finish the sliding doors, he finds that the weight of the plastering or something has caused the floor to settle and the track is out of level. Well, about nine carpenters out of ten will put the head-jamb level, which will bring one end of the jamb down from the track just as much as the floor is out of level. The consequence is that when the doors slide back, one of them will rub the head-jamb and quite likely stick fast. The head-jamb belongs snug up to the bottom edge of the track, as shown in Fig. 56, and there is where it should be placed, even if the track is out of level. To level the head-jamb when the track is not level only makes matters worse. A doorway with the head-jamb slightly out of level will not be noticed, but a door that will stick fast will be noticed every time it is opened. Of course I advocate doing the work correctly in the first place, and am now showing what to do in cases of emergency. Sometimes it is necessary to rabbet the head-jambs at the lower portion of the inside edge, as shown by the dotted lines in Fig. 56. Again, some workmen do not plow the groove in the bottom edge of the door deep enough for the floor guide. It might work when the door was first fitted, but a little settling of the track would cause binding of the door. This can be easily remedied by letting the floor guide into the floor, or by taking the door down and plowing the groove deeper. The former is the easiest and quickest and in every way just as good. The binding of sliding doors is often caused by the door stops being placed too close to the doors. When this is the case a removal of the stops and placing them a little farther away will remedy the trouble.
In hanging sliding doors it is better, if possible, to do so before the jambs are set. Many times little things that would interfere with the proper working of the doors can be easily remedied ; whereas, if the jambs were set, they would be concealed from general view and not discovered until they had caused a considerable amount of trouble. Is there any difference in door hangers ? is a question which very naturally arises. In our estimation there is considerable difference, although any of them, I think, would give satisfaction if every part of the work in putting them up was done in a substantial manner. Some hangers have more points of excellence than others, but I think the Prescott hanger the nearest perfection. With this hanger there is no track and no rollers. The doors hang suspended from the back edge, the hangers being fastened to the studding back of the jambs. They are as nearly frictionless as a door swinging on hinges, and there is no binding of doors from tracks and rollers. In fact, there is no more chance for the doors to bind from settling partitions than there is with the ordinary swinging doors on common hinges. Of the double-track overhead hangers, I think the Annex a very good specimen. All parts of the hanger are accurately fitted and the adjustment is as good as could be desired. The Standard door hanger is another good specimen, and I think sometimes it will allow doors to work free and easy under circumstances which other overhead hangers would not.