The Music Box

MuensterMann

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Mar 23, 2008
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Time to fix mom's cuckoo that dad hauled back from Germany in the early 70s! It is a chalet style with music box, guy chopping, two guys sawing, and water wheel spinning. You know the type!

Yep, it is dirty. The bellows have disintegrated. The music box frozen. However, all the parts are there.


Okay, the music box. It has two main problems other than being dirty: 1) the drum is not attached firmly to the axle and 2) the fly worm drive cannot be driven by the plastic gear.

Question 1: How does the drum attach to the axle? Pressure? Solder? Right now the axle turns, but the drum does not. The other problem is that the drum does not stay aligned to the tuning rods, since it can slide.

Question 2: The plastic gear that drives the worm drive of the fly is not stripped, but it cannot move the worm drive at all. I noticed that although the gear is not stripped, the teeth look oddly shaped. Could it be that this odd shape is the culprit from being worn? Common culprit? I am looking to see how I can find a new gear - suggestions?

Thanks!!
 

shutterbug

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I think I'd just get a new music box. Much less hassle :)
 

Dean Williams

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Question 2: The plastic gear that drives the worm drive of the fly is not stripped, but it cannot move the worm drive at all. I noticed that although the gear is not stripped, the teeth look oddly shaped. Could it be that this odd shape is the culprit from being worn? Common culprit? I am looking to see how I can find a new gear - suggestions?
Maybe you know this, or maybe not; On a worm drive that has one gear that is shaped like a screw (the worm) and the other that
looks mostly like a regular wheel, (the gear), it will only turn by putting torque on the shaft that rotates the worm. It can't turn by
trying to rotate the regular gear. Not if the worm and gear are at a 90 deg angle to each other, at least. Does that make sense?
About the odd shape, you could be seeing the normal shape of the gear teeth. The tooth shape of the gear that is run by the worm
are kind of a slanted orientation, so they could be the way they were intended.
Don't know for sure how the drum is attached. Could be a tiny set screw or taper pin that has been finished off flush, but broken
off inside. Look at the ends of the drum with a loupe to see what you can find. I don't think it would be solder, but have been wrong
before. Even before today...
 

MuensterMann

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Mar 23, 2008
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Thanks Dean! Yes, the gear teeth are slanted. Ah, okay, so this is normal. Good.

I do not understand fully your one worm sentence that basically says that "The worm screw cannot turn by rotating the gear (the regular wheel driving the worm)." How else would you get the worm screw and thus fly to rotate?

I cannot rotate any of the gears that are driven by the shaft of the drum with the worm/fly in the sequence of gears. If I remove the worm/fly from the sequence, then all the gears rotate. I belief is that my holdup is the gear to worm interface.
 

David S

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What Dean is saying is that you can't rotate the driven gear ie the one that the worm drives. In order to get the train to move you must rotate the worm.... if when you rotate the worm, or try to and it won't move then there is a bind somewhere. It is just that you can't drive a worm from the upstream train.
David
 

Tinker Dwight

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Oct 11, 2010
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Hi
On a music box, they drive the worm gear backwards.
The large wheel drives the worm!
A worm gear is usually of such high friction that it can't
be driven backwards but In the case of the music
box the high friction is actually part of the speed regulation.
As the fan spins, it increases drag and causes the friction
of the worm gear to slow it down.
The fan and worm pivots must be allmost frictionless or the
worm locks up and doesn't work.
Tinker Dwight
 
Last edited:

MuensterMann

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Yes, that makes more sense to me. The force is on the driving gear (large wheel). It has to move the worm. If the music drum is not locked and the fly is not blocked, then the force from the weight over to the drum axle and over to the driving gear and to the worm - will make the entire train move.

Okay, if that is correct, the fact of the matter is that my driving gear is not moving the worm. Not sure if it is the worm grooves or the driving gear teeth - but the combo does not function. Just wondering if there is something I can do to resolve the problem (apart from buying a new music box or governor assembly). Thanks!
 

dAz57

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have you oiled the worm gear? generally the pivots of the drive wheel and the other wheel & pinion meshed to it wear badly and bind up the music train, normally you don't oil wheel teeth in clocks, the exception is escape wheels and worm drives
 

shutterbug

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I've seen one or two where the wheel came loose and just spins so it can't control the governor.
 

MuensterMann

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After lubricating the worm there seems to be some success! I now know that it works or can work - so I will continue my cleaning of the music box assemblies.

As for the drum, we have a cylindrical hollow drum with caps on both sides. The caps have holes in the center for the axle to fit through. The cap closest to the click wheel is the one that locks the drum in place on the axle. The axle has a taper on that side in which the cap hole is pushed on until tight.

Unfortunately this cap hole is bigger than the widest circumference of the taper! Thus, I cannot lock it - by friction fit. The closest that I come is when the cap is put on crooked - that is, slightly outside the plane being perpendicular to the axis. However, I cannot get it to stay in that position.

Is there a trick to add material to the taper or to make the cap hole slightly smaller? I believe the cap material is aluminum. Any other ideas?
 

MuensterMann

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Mar 23, 2008
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I was reading another message on the board about something oozing out after cleaning. I think it was related to a music box. Anyway, could it be that the drum is held to the axle by some glue or silicon?
 

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