I finally fixed my issue with the cannon! Recapped here in its entirety:
SYMPTOM: Frequently (but intermittently) the cannon shot would fail to move up and down, instead freezing in place. Also noticed that the ship calibration could not get single digit speeds, seeming to lose steam around 12-14.
DIAGNOSIS: Running the ship test seemed to work fine at higher speeds. Initially I took this to mean there were no physical issues with the ship movement. On closer examination, it felt like the ship wasn’t listing to the left as much as it should. I pulled the playfield into the service position and repeated the test where I could now see the motor assembly was bending upon each revolution:
The reason for this was the adjustment bar which set set to the full topmost extent. This was causing the pin that moves the ship to halt against the top of the slot in the wood, causing the motor to press down and bend its bracket in order to keep moving.
FIX: After adjusting the screws to allow full range of movement, the ship now freely operates:
Additionally, the calibration test is now able to run all the way down to 4.
I am very happy to have this issue resolved, which is my last open problem with the game.FD3CEFF7-BB9E-4161-A94F-75BA45F6F20A (resized).jpegE1C1D172-687E-471E-ACE8-D8C2A16ED18C (resized).jpeg