Reply by Loren

I think it’s because the screws loosen over
time. The hinge may hold up but if it starts
to move around on a loose screw then you
have a problem.

Don’t use soft woods for shimming cup hinge
mount plates flush either. Don’t ask how
I know. Shimming also allows you to put a
longer screw in. Poggenpohl and other high
end frameless builders use those 5mm Euro
screws or the expanding plug hinges. Speed
is one reason, but I also think they’ve got it
down to a science and they know these
methods hold up.

If it’s stuff for yourself or family members
feel free to experiment but you don’t want
to give an open-ended warranty to a client
and have them calling you back because a
few hinges have gone loosey-goosey. You
may think you can tell them to tighten the
screws and maybe that will work once or
twice but in times the threads cut in the
face frame by the screw may get sloppy
and then the holes will have to be plugged
and re-drilled. New hinges are cheap if a
spring breaks and fixing stripped screw holes
outside the workshop is a pita, imo. Are
you going to glue a plug in there and go
to lunch and drill the hole after? Fine, but
it still eats up half a day making such a
house call.

Perhaps there are better face frame cup hinges
on the market than the ones I’ve used a
few times.

YMMV.