Mine held up well something i would attribute to having roughened up the hardware by sanding first.
How to touch up clear coat on door handles.
I reinstalled the door hardware being careful to not scratch the knobs as i screwed them in.
You could certainly try a clear coat.
Use plumber s blue tape and masking paper to mask off the area to be repaired.
Clear coat damage is caused by a number of factors but the primary culprit is the sun s uv rays the same rays that crack your dashboard fade your carpets and cloth upholstery and cause plastic rot on interior trim panels.
I put a piece of painter s tape around each knob to ensure this wouldn t happen.
After refinishing your old door hardware you might notice that some of the paint in the middle of the screw heads might have come off when you installed them.
If the clear coat damage is confined to a local area wash the area removing all oil dirt and wax.
Dry the paint with clean towels.
In response to the baldwin clear coat a commercial paint stripper will remove the urethane coating.
Spray a coat of clear coat onto the car door handles.
It wouldn t hurt and might help.
Jasco or a similar product.
Ultraviolet light slowly degrades the outer layer of paint protection burning it white and rough.
Cover door handles keyholes door guards and trim pieces.
Spray a total of three coats of clear coat.
The author suggested spraying a clear acrylic coat on doorknobs as a means of protection not only from the elements but from scratching the paint off due to handling keys etc.
Let the clear coat dry for three hours or as recommended by the manufacturer.
If a door or fender panel needs clear coat mask off the seam of the panel.
I didn t see where you said you d sprayed a clear coat on your doorknobs so this may be something for you to consider and test for longevity of the finish.
Good luck with your project.
Remove the masking tape from the edges of the car door handles.