Quoted from iceman44:
Try unscrewing that metal post that taps the cup a little bit to have it make better contact. Worked for me
Okay, took my Orb captive ball apart yesterday and found that if I tightened the retaining ring that holds the spring a little bit tighter I could make a bit more space between it and the outer retaining ring, which allows the captive ball to tilt more freely without binding on the outer ring. This makes it feel more smooth like my sarcophagus one does. I also lubed the metal on metal part with some synthetic grease.
However, the only thing that made the actual switch work reliably without mis-firing was to unscrew the metal bottom post that touches the plastic spoon about two full rotations to give it a little more length (as you noted). This increases the leverage that the tilting ball can apply to to the spoon. Mine was really loose though and vibrations from firing coils would make it keep turning so I applied some locktight to the threads and let it dry. After a bunch of games last night it continues to work perfectly, we'll see if it holds up.
So it would seem that Stern should either use a slightly longer bottom post or a slightly shorter bracket for the switch/spoon mech.
Now my sarcophagus captive ball fires perfectly when it's empty, but not at all if a ball is loaded in it. I'm thinking that the sw must register a hit if the top switch in the trough is closed by the second ball since the front ball doesn't move at all but simply transfers all the energy to the second ball? I need to test this to see if it's that case. I've been having trouble getting that switch adjusted to actually work and so for no luck. I guess I'll order the roller style switches as well. This seems like a really common problem with this mech, you think Stern will issue a service bulletin?