You have a nice old cuckoo worth restoring. I would repair the top piece by gluing the break and once dry, glue a thin piece on the back side over the seam for strength. The bellows don't appear original to me because of the plastic portion of the pipes. Bellows and hands can be...
A and B weren't designed to contact each other. A is a part of the motion works and is called an idler gear transferring motion from one wheel to another. B pushes on the lifting lever to start the chime/strike functions. I think that what you are seeing is the remnants of the machining process.
I agree with the David LaBounty recommendation, I borrowed it from the library. Also, Conover's Chime Clock Repair book will give you tips for this and other brands.
If your clock has plated pivots, you might be gentle when polishing. Even so, it will be fun to work on!
I would chamfer the plate on both sides then select a taller bush and use a round nose punch or a ball bearing and rivet it tight. File the excess flush. You could also make a custom bushing and install.
I have done what you are suggesting and it works but it isn't pretty.
I see most (jewelers) regulators for sale at auction sites. They can go anywhere from a couple of thousand to tens of thousands of dollars. They will be time only, seconds beat, weight driven, dead beat escapement, maintaining power and pendulum.
I do think that Knock on wood had their customers best interest in mind. Considering stopping the pendulum before winding: while thinking of the action of winding a clock, the case might be jostled some or just the lack of power while winding could cause the pendulum to stop or ew. teeth...
My shop is in the basement with no real natural light. The area that I use is about 12' by 10' with overhead and task lighting and in an L-shape using two benches. I have my lathe and mill on one bench and it's height is roughly counter height. My assemble/disassemble bench is lower (too...
What about the rack, was that cleaned? Does it move easily with no sticking if you move the rack hook out of the way? I might have to see a video posted here from youtube. Let it strike at 12 then move the minute hand to 1:00 so that we can see. I don't think that I could do any repair with...
If there is enough brass, I've use a fine triangle file to cut the teeth deeper. There are replacement ratchet wheels available if needed. I see a bent tooth on the second wheel and wouldn't be surprised if there were worn lantern pinions and bushings needed too.
I'm sure that they were mass produced, it's just there could be a difference in wear in the parts and like I said, making adjustments by eye. Here is some info on strike train set up from the (Sticky Threads Section) of this forum.
To start, take a look and make sure the cable is still on each drum and not wrapped around the arbors. You might want to take the dial off to see what's going on. Take some clear photos of the movement and post here.