We recently had all of the doors in our house replaced. Due to the age and style of the house we decided that our rosewood mortice door knobs would go well with the traditional panelled oak doors.
The installation process brought up lots of issues. I thought I would share my experience as these issues are often experienced by customers.
Pilot Drill Bit
Choosing a latch/lock
The first thing that you need to take into consideration is the length of your tubular latch or mortice lock. With a traditional lever handle, the handle operation is away from the edge of the door. A door knob, however, sits closer and your knuckles could hit the door surround. With that in mind we would recommend using a latch that has at least 3.5 inches (90mm) from the surface of the plate to the center of the mortice opening.
Another important consideration is the strength of the spring within the mechanism. With most lever handle sets there is a spring usually built into both left and right handles, which, combined with the spring in the latch leads to a very positive movement. Our mortice beehive knobs are un-sprung therefore it is crucial that the latch chosen has a heavy-duty spring. Please see our collection of suitable heavy duty tubular latches.
Fitting the Door Knob
With the latch installed it’s now time to fit the door knob. The first task is to set the threaded mortice bar so that there are equal amounts of bar on both sides of the door. Once you are happy this has been achieved secure the mortice bar into one of the knob using the allen key and grub screw.
This leads on nicely to another potential issue that needs some attention. You would have noticed that the mortice bar is square and screws into the knob via a round threaded hole. The most common complaint that I receive from customers about these knobs is that the thread has failed or unscrews. Upon investigation, it always is a result of the grub screw, which has been secured against one of the corners of the morice bars. Initially, the knob will work perfectly, but with repeated use the grub screw eventually slips off the mortice bar causing the knob to turn without operating the catch or unscrew altogether. Therefore, it is very important to make sure that the grub screw is always secured against the flat face of the mortice bar to ensure the knob will never fail or unscrew.
With the mortice bar securely fitted into one of the knobs pass the mortice bar through the latch with one of the rose plates. Place the remaining rose plate over the protruding mortice bar and wind the loose knob down the mortice bar until it come up against the shoulder of the rose plate. To avoid unnecessary friction its important to unscrew the knob anti-clockwise just enough to allow you to secure the second grub screw against the flat of the mortice bar. There is hole in the rose plate this allows access for screwing down the grub screw. Once secured, you can turn the rose plate so that the opening is pointing down and out of sight.
Fixing the Rose Plates
You are now ready to screw the rose plates into position. Drill a small single angled pilot hole on both sides of the door then fix the rose plates in position. Check to make sure the latch operates smoothly and without obstruction. If the catch sticks in any way an small turn on either of the rose plates will remedy any sticking. Once you are happy the handles are operating smoothly you can pilot drill and fix the rest of the holes.
I hope you found the tips helpful. If you have any questions please leave a comment below.