can we see better/more in focus pictures from both sides of the hour cannon? typically the snail/hour cannon gear will mesh with another smaller gear that trips the hour strike... but it's hard to see what's going on with yours. more photos, please!
Hmm. Don't squeeze anything until you understand how the thing works.
An Asian clock like this one uses a slightly odd system to secure the hour hand, which is mechanically locked on its pipe instead of being a friction fit. The hour hand should have two tabs in its hub. These mesh with the two grooves in the end of the hour pipe. It's possible that someone installed the wrong hour hand, or altered the original in an inadvisable manner. If the hour hand locks as it should, then something else is loose farther back. The hour hand can usually be turned independently on many of these along with the snail, which makes for strange motion work.
I see the minute wheel, but it doesn't seem to connect to anything inside the plates. It should be controlled by the minute arbor. There might be a pinion missing from the area just behind the front plate, on the center shaft.
Well, as I should have done before posting this, I took the cannon off the hour shaft and found a pressure washer at the base of the canon, behind the gear. Applied some finger pressure to this washer and the canon is now tight. Thanks for all the replies. I'll be back shortly with another clock, another problem.
When you see a keyed hour hand it nearly always goes with a clutch against the snail. This way the hour hand can be set independently from the minute hand and the hour count will always be correct.